Elemental Impurities

regulatory, Uncategorized Comments Off

Jul 112018

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Elemental Impurities

On January 1, 2018, new guidelines regarding elemental impurities in brand and generic drug products went into effect. Elemental impurities, such as arsenic and lead, pose toxicological risks to patients without providing any therapeutic benefit. These impurities may be present in drug products from a variety of sources, such as interactions with equipment during the drug manufacturing process.

FDA, together with other organizations, such as the International Council for Harmonisation (ICH) and the U.S. Pharmacopeial Convention (USPC), have engaged in long-standing efforts to best protect patients from the risks posed by elemental impurities by developing limits for their amounts in drug products, and standardized approaches to use in determining the amount of elemental impurities in these products.

As of January 1, 2018:

All new and existing NDAs and ANDAs for drug products with an official USP monograph are required to meet the requirements in USP General Chapters <232> and <233> for the control of elemental impurities.
Applicants submitting NDAs and ANDAs for drug products without a USP monograph are expected to follow the recommendations in the ICH Q3D Elemental Impurities guideline.

Questions and Answers on Elemental Impurities:

Why were these guidelines developed, and why are they important?

Heavy metal elemental impurities pose serious risks to patients without providing a benefit. Modern methods provide better analytical tests to detect elemental impurities, which in turn, will help protect patients by ensuring approved products have safe levels of these impurities. The ICH guidelines and USP General Chapters <232>Elemental Impurities—Limits are focused on establishing Permitted Daily Exposures (PDEs) for elemental impurities in drug products. USP General Chapter <233>Elemental Impurities—Procedures describes analytical approaches for the detection of elemental impurities. The analytical approaches described in <233> are based on modern analytical capabilities, replace the outdated tests in the deleted USP General Chapter <231> Heavy Metals, and allow us to more precisely measure impurities to ensure safe levels. FDA, ICH, USP, and industry experts worked together to develop the new standards that are in alignment and help ensure high quality medicines.

How has FDA been supporting industry to implement the requirements?

FDA, ICH, and USP have all engaged with brand and generic drug manufacturers to support implementation of these requirements. These requirements are the result of long-standing efforts, and both ICH and USP included industry participants on their expert panels that developed these standards. With that input, an implementation date was identified that provided firms with substantial time to verify their operations met the requirements.

In June 2016, FDA published a draft guidance, Elemental Impurities in Drug Products, to provide recommendations regarding the control of elemental impurities of human drug products. The draft guidance encouraged the early adoption of ICH Q3D guidelines and USP General Chapters <232> and <233> before the January 1, 2018 implementation date. FDA has also presented on this topic at conferences, including at a two-day ICH Q3D regional workshop it hosted in August 2016 ¹. These outreach efforts have supported efforts by industry to perform the risk assessments needed to implement the new guidelines in order to have complete, approvable applications. On an application-specific level, FDA began noting this requirement in complete response letters to applicants that contained quality deficiencies in Spring of 2017.

What should companies do if they have questions about elemental impurity standards?

Companies that have quality questions regarding elemental impurities and their applications should contact the Regulatory Business Process Manager (RBPM) in the Office of Program and Regulatory Operations, Office of Pharmaceutical Quality for their application. Applications that do not meet the elemental impurity guidelines are unable to be approved and applicants may receive a request for the information from the FDA in the form of an Information Request or a Complete Response letter. Firms should submit information on their elemental impurity risk assessments to FDA as soon as they are able, rather than waiting for a request from FDA, in order to minimize the impact on review and approval timeframes. The following resource may help applicants understand the process moving forward depending on where they are in the review process.

What is the International Council for Harmonisation?

ICH, first created in 1990 by regulatory agencies and both brand and generic drug manufacturing associations from the United States, Europe, and Japan, was established to facilitate international collaboration, and has been successful in standardizing and elevating drug development practices throughout the world. ICH’s mission helps to increase patient access to safe, effective, and high quality pharmaceuticals, and to ensure that pharmaceuticals are developed and registered efficiently. International harmonization of regulatory standards means that pharmaceutical manufacturers and developers will be held to the same standards in different markets (countries), which will make the development and delivery of quality pharmaceuticals to the public more timely and efficient. The ICH Website includes training modules on implementation of the Q3D elemental impurity guidelines.

What is the U.S. Pharmacopeia Convention?

The United States Pharmacopeia Convention (USPC) is a private non-profit organization that develops public standards related to pharmaceutical quality. USP General Chapters <232>Elemental Impurities—Limits, and, <233>Elemental Impurities—Procedures are applicable to compendial drug products as per Federal Food, Drug, and Cosmetic Act Sec. 201(j), and Sec. 501(b). USP’s website offers information regarding the history of actions they have taken on elemental impurities , as well as other FAQ .

¹ Other presentations include the Drug Information Association’s CMC Workshop 2015 , the Consumer Healthcare Products Association’s 2015 Regulatory, Scientific & Quality Conference , the Product Quality Research Institute (PQRI) / USP Workshop on ICH Q3D Elemental Impurities Requirements , the Generic Pharmaceutical Association (now Association of Affordable Medicines) CMC Workshop , the USP Excipients Stakeholder Forum, the PQRI/USP Workshop on Implementation Status of ICH Q3D , and the PQRI/USP Workshop on ICH Q3D Elemental Impurities Requirements – Recent Experience and Plans for Full Implementation in 2018

Elemental Impurities

Efforts in this area are currently focused on three fronts:

Finalization of risk assessments to ensure compliance with the ICH Q3D guideline for all products supplied to those markets having implemented ICH Q3D and to the date for implementation
Continued development of ICH Q3D dermal limits
Removal of the heavy metals limit test USP <231>

Marketed Product Compliance

When it was published at the end of 2014, ICH Q3D(1) provided a 3 year moratorium in relation to established products, meaning that all such products would have to demonstrate compliance with the guideline at the end of 2017. Many involved will testify to the Herculean effort required to complete this within large organizations where hundreds if not thousands of products were within scope. What has been the outcome? Informal feedback within the industry is that aside from a small number of products, organizations have found that the vast majority of products assessed require no additional control measures because they already have appropriate quality control measures.

Elemental Impurities within Excipients

The ICH Q3D guideline describes how a risk-based approach to the control of elemental impurities in drug products can be taken, highlighting within this that assessments should be data-driven. Options in terms of data include both data generated specific to a drug product and published data. In 2015 the U.S. Food and Drug Administration (FDA) and the European International Pharmaceutical Excipient Council (IPEC) jointly published the outcome of a focused study on some 200 excipient samples covering a range of excipients. This concluded that the overall risk associated with excipients, including those that are mined, was relatively low, especially when typical proportions in formulated drug products were considered. With the express aim of building upon this initial study, a consortium of pharmaceutical companies has established a database to collate the results of analytical studies of the levels of elemental impurities within pharmaceutical excipients. This database currently includes the results of over 25 000 elemental determinations for over 200 different excipients and represents the largest known, and still rapidly expanding, collection of data of this type.

A recently published analysis of the database(2) examined a series of aspects, including data coverage as well as impurity levels and variability (across supplier/grade, etc.). The database includes results from multiple analytical studies for many of the excipients and thus can give a clear indication of both excipient supplier and batch-to-batch variability as well as any variability associated with the different testing organizations and methods employed. The results are telling. Critically, the data confirm the findings of earlier, smaller FDA–IPEC studies showing that elemental impurity concentrations in excipients, including mined excipients, are generally low and when used in typical proportions in formulated drug products are unlikely to pose a significant patient safety risk.

The database is now in active use within member organizations, providing real evidence in support of holistic ICH Q3D risk assessments and in the future potentially significantly reducing the need for testing. However, it is necessary to recognize that there was a sense that mined excipients could still present a risk over the long term. That variability in elemental impurity levels within mined excipients will vary over time, and further data will be required. There is therefore a need for continued collaboration between the pharmaceutical industry and excipient manufacturers.

It is interesting to reflect that had such studies been conducted ahead of finalization of ICH Q3D, it is possible that it would have allowed us to eliminate concerns about elemental impurities, at least for some low-risk excipients Another study could have achieved the same outcome for manufacturing equipment.

Removal of Heavy Metals Testing

Perhaps our biggest challenge as an industry in this area relates to the potential to remove existing empirical testing for elemental impurities using the wet-chemistry heavy metals limit test because of differences in the global regulatory landscape. In the case of the United States Pharmacopeia (USP), this takes the form of the now-deleted USP Chapter <231>.

On the basis of the time scale for implementation of ICH Q3D, most organizations are well-advanced in terms of the risk assessment of current products, as described above. In the clear majority of cases, this successfully demonstrates that the heavy metals test does not provide any additional control for elemental impurities. On this basis, it should therefore be possible to remove the heavy metals limit test, of which USP <231> is the most prevalent example.

The situation in the U.S. is that removal is relatively straightforward, as the test has already been removed from the USP. A statement to confirm completion of an elemental impurity risk assessment is then provided in the product annual update. Elsewhere, the situation is more challenging. In Europe there is no definitive position, but filing a simple show-and-tell type 1A variation seems to provide a pathway. Thereafter, the situation is considerably more complex.

In Japan, the equivalent of the USP <231> test has been retained in the Japanese Pharmacopeia (JP). Consequently, removing the test from an existing product (one where a monograph is published and it includes such a test) may require submitting a product-specific request to revise the individual monograph. It is also anticipated that removal of the test from approved but not monographed products will also require a post-approval change submission.

In China, the Chinese Pharmacopeia (CP) will retain the test until at least 2020, and the indication is that the test should still be performed where registered.

Outside of ICH regions, the situation is still more complicated. Given the prevalent position of the USP in many countries, API and product specifications often include USP <231>. However, this test no longer exists! The challenge then concerns whether the test can be removed and the specification revised, and if so, how this should be done. The scale of this is significant, especially if a formal variations procedure is needed. One apparent option is to continue testing, but even this is complicated, as it is not clear how one could continue to use a test that no longer exists in the USP. Some organizations have even considered developing a “USP <231>-like” test.

Clearly, organizations do not want to continue to use an empirical test when a risk assessment has shown that it adds no value, but at present there is no obvious way to resolve this conundrum for globally marketed products until significant harmonization in compendial test requirements is achieved.

REFERENCES

1 Guideline for Elemental Impurities Q3D, Current Step 4 version, dated Dec 16, 2014.

2 Boetzel, R.; Ceszlak, A.; Day, C.An Elemental Impurities Excipient Database: A Viable Tool for ICH Q3D Drug Product Risk Assessment. J. Pharm. Sci. 2018, DOI: 10.1016/j.xphs.2018.04.009

3 https://www.ich.org/fileadmin/Public_Web_Site/ICH_Products/Guidelines/Quality/Q3D/Q3D_Step_4.pdf

4 https://www.fda.gov/downloads/drugs/guidances/ucm371025.pdf

5 https://www.fda.gov/drugs/developmentapprovalprocess/manufacturing/ucm590075.htm

//////////Elemental Impurities, ICH Q3D, USP

ICH Q12: Guideline on Technical and Regulatory Considerations for Pharmaceutical Product Lifecycle Management

Uncategorized Comments Off

Jul 062018

ICH Q12: Guideline on Technical and Regulatory Considerations for Pharmaceutical Product Lifecycle Management, 1-2

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Recent ICH quality guidelines (Q8–Q11)(3−6) have focused on providing guidance on the development and manufacture of drug substances (Q11)(6) and drug products (Q8),(3) showing “baseline” and “enhanced” scientific approaches, and utilizing quality risk management tools (Q9) within the pharmaceutical quality management system (Q10). To further support the implementation of these development and manufacturing approaches, ICH recognized the value in providing tools and approaches for the management of post-approval chemistry, manufacturing, and controls (CMC) changes based on product and process understanding that could be employed by all ICH participants. Several useful tools had been established in different regions, and it was recognized that pharmaceutical innovation and continuous improvement would be optimally supported if best practices could be employed in similar ways across the regions. Achieving this harmonization would result in more efficient manufacture and change and would also increase the value of the pharmaceutical quality system and support continued optimization of the utilization of valuable resources within regulatory agencies and inspectorates (e.g., toward oversight of critical rather than noncritical changes, incentivizing industry’s understanding and management of manufacturing). The ICH Concept Paper for the development of this guidance was endorsed in 2014.(7)

The drafted consensus document is now available for public comment (step 2 of the ICH process),(8) with comments being collected by the regions during 2018 (with various comment deadlines).

The draft guidance includes some potentially very important approaches for future CMC change management, and importantly, the tools and approaches being developed are seen as usable across the range of pharmaceutical product types (including drug–device combinations) and applicable to existing products as well as newly approved products.

An approach of particular importance that is included in the guideline is the “post-approval change management protocol” (PACMP), which allows for specific changes to be predescribed to regulators and agreement to be reached on the scientific approach and data expectations that will support the change. This ability to predefine how to successfully make a change will bring great clarity and predictability to the planning and prosecution of, particularly, complex change types (often viewed as major changes needing “prior approval” in current regulatory change systems). Furthermore, the predetermination of data necessary to support the change allows for the final communication of the change to be a simple matter of confirming the suitability of the change with the expected data and for the regulatory change class to be reduced on the basis of the prior agreement of the change management approach. Importantly, a PACMP can be either agreed for a single change for a single product or constructed and agreed in a more wide-ranging manner to support multiple similar changes to be conducted on more than one product. This is of immense potential value to industry and regulators alike. Annex II of the draft guideline provides illustrative examples of different types of PACMPs, giving an example of a PACMP for a single change (to a manufacturing site for a drug substance) and an example of the more general management of such a site change.

In a section of the guideline on supporting post-approval changes for marketed products, where considerable manufacturing experience has been accrued, important approaches are given for the management of changes in analytical procedures and discussing how data requirements for changes (for stability data) can be impacted by product and process understanding.

In addition, the guidance seeks to provide an approach to differentiate the levels of regulatory oversight of particular changes on the basis of known impact and criticality of the potential change to product quality. The ability to differentiate change expectations on the basis of actual product understanding is a natural extension of the approaches taken in ICH Q8 and Q11, where for example product and process understanding can establish a “Design Space” for manufacturing and control within which changes are not seen as requiring regulatory oversight. In the draft of Q12, this concept is further developed by the concept of “Established Conditions” (ECs), with discussion of how investment in understanding can impact submission expectations (with Appendix I of the draft guideline providing an illustration of CTD sections that contain ECs and Annex I suggesting illustrative examples of ECs for both chemical products and biological products) and post-approval change management expectations. Importantly, the guidance discusses how this approach could be used for existing products, where the manufacturing process may have been described without any differentiation of change management expectations, leading to inefficient use of both industry and regulatory resources.

The draft guideline also includes a suggested system for the collation of such “agreed” regulatory change mechanisms for a product via use of a product lifecycle management (PLCM) approach, wherein the agreed changes can be clearly collated alongside the manufacturing commitments and the agreed (lesser) change reporting category for the changes. Annex III of the draft documentation provides an example of a PLCM document.

The guideline also contains content describing the pharmaceutical quality system (PQS) change management expectations (with Appendix II of the guideline providing further illustration of principles of change management) and the relationship between industry and regulators and importantly between regulatory assessment and inspection needed to support strong implementation of the approaches within Q12.

The draft guideline clearly already provides tools and approaches for change management of immense potential value. Nevertheless, the opportunity to comment on the draft is always an important step in the development of an ICH guideline, and it is important to ensure that comments assist in providing the clearest possible final guidance that will be readily and consistently implemented to mutual industry and regulator benefit. It is noteworthy that the current draft of the guideline includes wording suggesting that some concepts may not be implementable at the current time across every region. It will be of greatest benefit if the tools and approaches as described and agreed in the finalized guidance will be available for use on as wide a global basis as possible, in line with the ongoing vision of ICH for science-based, harmonized, and efficient regulation of pharmaceuticals.

1 http://www.ich.org/fileadmin/Public_Web_Site/ICH_Products/Guidelines/Quality/Q12/Q12_DraftGuideline_Step2_2017_1116.pdf

2 http://www.ich.org/products/guidelines/quality/quality-single/article/technical-and-regulatory-considerations-for-pharmaceutical-product-lifecycle-management.html

3 Pharmaceutical Development Q8(R2), Current Step 4 version, dated August 2009.

4 Quality Risk Management Q9, Current Step 4 version, dated Nov 9, 2005.

5 Pharmaceutical Quality System Q10, Current Step 4 version, dated June 4, 2008.

6 Development and Manufacture of Drug Substances (Chemical Entities and Biotechnological/Biological Entities) Q11, Current Step 4 version, dated May 1 2012.

7 Final Concept Paper Q12: Technical and Regulatory Considerations for Pharmaceutical Product Lifecycle Management, dated July 28 2014, endorsed by the ICH Steering Committee on Sept 9, 2014.

8 Technical and Regulatory Considerations for Pharmaceutical Product Lifecycle Management Q12, draft version endorsed on Nov 16, 2017.

////////////////ICH Q12, Guideline, Technical and Regulatory Considerations, Pharmaceutical Product, Lifecycle Management

Amelioration of diethylnitrosamine (DEN)-induced hepatocellular carcinogenesis in animal models via knockdown oxidative stress and proinflammatory markers by Madhuca longifolia embedded silver nanoparticles

nanotechnology, Uncategorized Comments Off

Jun 122018

Amelioration of diethylnitrosamine (DEN)-induced hepatocellular carcinogenesis in animal models via knockdown oxidative stress and proinflammatory markers by Madhuca longifolia embedded silver nanoparticles

http://pubs.rsc.org/en/content/articlepdf/2018/ra/c7ra12775h

DOI: 10.1039/c7ra12775h

rsc.li/rsc-advances

RSC Adv., 2018, 8, 6940–6953

Deepika Singh, a Manvendra Singh,b Ekta Yadav,a Neha Falls,a Ujendra Komal,c Deependra Singh Dangi,d Vikas Kumare and Amita Verma*f

Department of Pharmaceutical Science, Faculty of Health Sciences, Sam Higginbottom University of Agriculture, Technology and Sciences, Allahabad, 211007, India

b HMFA Institute of Engineering & Technology, Handia, Allahabad, 211007, India

c Department of Mechanical & Industrial Engineering, Indian Institute of Technology, Roorkee, Uttrakhand, India

d Kinapse India Scientic Services Pvt. Ltd., Gurgoan, Haryana, India

e Natural Product Drug Discovery Laboratory, Department of Pharmaceutical Sciences, Faculty of Health Sciences, Sam Higginbottom University of Agriculture, Technology & Sciences, Allahabad, Uttar Pradesh 211007, India

f Bio-organic & Medicinal Chemistry Research Laboratory, Department of Pharmaceutical Sciences, Faculty of Health Sciences, Sam Higginbottom University of Agriculture, Technology & Sciences, Allahabad – 211007, Uttar Pradesh, India.

E-mail: amitaverma.dr@gmail.com; amita.verma@shiats.edu.in

In hepatocellular carcinoma (HCC), primary liver cancer is primarily responsible for inflammation-related cancer as more than 90% of HCCs emerge with regard to hepatic damage and inflammation. Tenacious inflammation is known to advance and intensify liver tumours. Nanomaterials, for example, silver nanoparticles synthesized from plant-derived materials have shown great outcomes in reducing the precancerous nodules and have anticancer properties. The aim of the present investigation was to biosynthesize, characterize and evaluate the anticancer activity of nanoparticles-embedded Madhuca longifolia extract (MLAgNPs) on an experimental model of hepatic cancer in rats. M. longifolia contains a high amount of flavonoids and other phenolic derivative. The silver nanoparticles synthesized by M. longifolia were characterized by various instruments, including UV-Vis spectrophotometry, X-ray beam diffraction, field-emission scanning electron microscopy with energy dispersive X-ray analysis, transmission electron microscopy and Fourier transform infrared spectroscopy. Liver cancer was induced to 36 Wistar rats by a single dose of diethylnitrosamine (DEN) (200 mg kg1 BW). Hepatic cancer by MLAgNPs dose-dependently limited macroscopical variation compared with the DEN-induced hepatic cancer groups. The serum and liver were taken to measure the antioxidant parameters, proinflammatory cytokines and for a histopathological study. Serum hepatic and serum non-hepatic along with inflammatory cytokines were also assessed. Reduction in the levels of proinflammatory cytokines, namely tumour necrosis factor-a, interleukin-6, interleukin-1b, nuclear factor kappa beta (NF-kB), and improved membrane-bound enzyme activity were also detected. It was found that minor morphological anomalies were identified in the histopathology analysis in the MLAgNPs-treated groups. It could be concluded that silver nanoparticles introduce an extraordinary potential for use as adjuvants in hepatic cancer treatment because of their antioxidant abilities and ability to diminish inflammation in liver tissue by attenuating the NF-kB pathway.

Conclusion Our outcomes have demonstrated that the bioengineered silver nanoparticles of M. longifolia leaves extract cause in vitro and in vivo apoptosis of hepatic cancer through an ROS pathway and are promising agents in liver carcinogenesis.

DR AMITA VERMA

Professor at Sam Higginbottom University of Agriculture, Technology and Sciences
Studied Ph.D at Jamia Hamdard University

Bio-organic & Medicinal Chemistry Research Laboratory, Department of Pharmaceutical Sciences, Faculty of Health Sciences, Sam Higginbottom University of Agriculture, Technology & Sciences, Allahabad – 211007, Uttar Pradesh, India.

E-mail: amitaverma.dr@gmail.com; amita.verma@shiats.edu.in

Sam Higginbottom University of Agriculture, Technology and Sciences

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Expansion of First-in-Class Drug Candidates That Sequester Toxic All-Trans-Retinal and Prevent Light-Induced Retinal Degeneration s

Uncategorized Comments Off

Jun 042018

ABSTRACT All-trans-retinal, a retinoid metabolite naturally produced upon photoreceptor light activation, is cytotoxic when present at elevated levels in the retina. To lower its toxicity, two experimentally validated methods have been developed involving inhibition of the retinoid cycle and sequestration of excess of all-trans-retinal by drugs containing a primary amine group. We identified the first-in-class drug candidates that transiently sequester this metabolite or slow down its production by inhibiting regeneration of the visual chromophore, 11-cis-retinal. Two enzymes are critical for retinoid recycling in the eye. Lecithin:retinol acyltransferase (LRAT) is the enzyme that traps vitamin A (all-trans-retinol) from the circulation and photoreceptor cells to produce the esterified substrate for retinoid isomerase (RPE65), which converts all-trans-retinyl ester into 11-cis-retinol. Here we investigated retinylamine and its derivatives to assess their inhibitor/substrate specificities for RPE65 and LRAT, mechanisms of action, potency, retention in the eye, and protection against acute light-induced retinal degeneration in mice. We correlated levels of visual cycle inhibition with retinal protective effects and outlined chemical boundaries for LRAT substrates and RPE65 inhibitors to obtain critical insights into therapeutic properties needed for retinal preservation.

http://molpharm.aspetjournals.org/content/early/2014/12/23/mol.114.096560

Expansion of First-in-class Drug Candidates that Sequester Toxic All-trans-retinal and Prevent Light-induced Retinal Degeneration

, Zhiqian Dong, Sreenivasa Mundla, X Eric Hu, , , and Marcin Golczak

Molecular Pharmacology December 23, 2014, mol.114.096560; DOI: https://doi.org/10.1124/mol.114.096560

Sreeni Labs Private Limited, Hyderabad, India is ready to take up challenging synthesis projects from your preclinical and clinical development and supply from few grams to multi-kilo quantities. Sreeni Labs has proven route scouting ability to design and develop innovative, cost effective, scalable routes by using readily available and inexpensive starting materials. The selected route will be further developed into a robust process and demonstrate on kilo gram scale and produce 100’s of kilos of in a relatively short time.

Accelerate your early development at competitive price by taking your route selection, process development and material supply challenges (gram scale to kilogram scale) to Sreeni Labs…………

INTRODUCTION

Sreeni Labs based in Hyderabad, India is working with various global customers and solving variety of challenging synthesis problems. Their customer base ranges from USA, Canada, India and Europe. Sreeni labs Managing Director, Dr. Sreenivasa Reddy Mundla has worked at Procter & Gamble Pharmaceuticals and Eli Lilly based in USA.

The main strength of Sreeni Labs is in the design, development of innovative and highly economical synthetic routes and development of a selected route into a robust process followed by production of quality product from 100 grams to 100s of kg scale. Sreeni Labs main motto is adding value in everything they do.

They have helped number of customers from virtual biotech, big pharma, specialty chemicals, catalog companies, and academic researchers and drug developers, solar energy researchers at universities and institutions by successfully developing highly economical and simple chemistry routes to number of products that were made either by very lengthy synthetic routes or by using highly dangerous reagents and Suzuki coupling steps. They are able to supply materials from gram scale to multi kilo scale in a relatively short time by developing very short and efficient synthetic routes to a number of advanced intermediates, specialty chemicals, APIs and reference compounds. They also helped customers by drastically reducing number of steps, telescoping few steps into a single pot. For some projects, Sreeni Labs was able to develop simple chemistry and avoided use of palladium & expensive ligands. They always begin the project with end in the mind and design simple chemistry and also use readily available or easy to prepare starting materials in their design of synthetic routes

Over the years, Sreeni labs has successfully made a variety of products ranging from few mg to several kilogram scale. Sreeni labs has plenty of experience in making small select libraries of compounds, carbocyclic compounds like complex terpenoids, retinal derivatives, alkaloids, and heterocyclic compounds like multi substituted beta carbolines, pyridines, quinolines, quinolones, imidazoles, aminoimidazoles, quinoxalines, indoles, benzimidazoles, thiazoles, oxazoles, isoxazoles, carbazoles, benzothiazoles, azapines, benzazpines, natural and unnatural aminoacids, tetrapeptides, substituted oligomers of thiophenes and fused thiophenes, RAFT reagents, isocyanates, variety of ligands, heteroaryl, biaryl, triaryl compounds, process impurities and metabolites.

Sreeni Labs is Looking for any potential opportunities where people need development of cost effective scalable routes followed by quick scale up to produce quality products in the pharmaceutical & specialty chemicals area. They can also take up custom synthesis and scale up of medchem analogues and building blocks. They have flexible business model that will be in sink with customers. One can test their abilities & capabilities by giving couple of PO based (fee for service) projects.

Some of the compounds prepared by Sreeni labs;

See presentation below

LINK ON SLIDESHARE

Sreeni Labs Profile from Sreenivasa Reddy

Managing Director at Sreeni Labs Private Limited

Few Case Studies : Source SEEENI LABS

QUOTE………….

One virtual biotech company customer from USA, through a common friend approached Sreeni Labs and told that they are buying a tetrapeptide from Bachem on mg scale at a very high price and requested us to see if we can make 5g. We accepted the challenge and developed solution phase chemistry and delivered 6g and also the process procedures in 10 weeks time. The customer told that they are using same procedures with very minor modifications and produced the tetrapeptide ip to 100kg scale as the molecule is in Phase III.

One East coast customer in our first meeting told that they are working with 4 CROs of which two are in India and two are in China and politely asked why they should work with Sreeni Labs. We told that give us a project where your CROs failed to deliver and we will give a quote and work on it. You pay us only if we deliver and you satisfy with the data. They immediately gave us a project to make 1.5g and we delivered 2g product in 9 weeks. After receiving product and the data, the customer was extremely happy as their previous CRO couldn’t deliver even a milligram in four months with 3 FTEs.

One Midwest biotech company was struggling to remove palladium from final API as they were doing a Suzuki coupling with a very expensive aryl pinacol borane and bromo pyridine derivative with an expensive ligand and relatively large amount of palldium acetate. The cost of final step catalyst, ligand and the palladium scavenging resin were making the project not viable even though the product is generating excellent data in the clinic. At this point we signed an FTE agreement with them and in four months time, we were able to design and develop a non suzuki route based on acid base chemistry and made 15g of API and compared the analytical data and purity with the Suzuki route API. This solved all three problems and the customer was very pleased with the outcome.

One big pharma customer from east coast, wrote a structure of chemical intermediate on a paper napkin in our first meeting and asked us to see if we can make it. We told that we can make it and in less than 3 weeks time we made a gram sample and shared the analytical data. The customer was very pleased and asked us to make 500g. We delivered in 4 weeks and in the next three months we supplied 25kg of the same product.

Through a common friend reference, a European customer from a an academic institute, sent us an email requesting us to quote for 20mg of a compound with compound number mentioned in J. med. chem. paper. It is a polycyclic compound with four contiguous stereogenic centers. We gave a quote and delivered 35 mg of product with full analytical data which was more pure than the published in literature. Later on we made 8g and 6g of the same product.

One West coast customer approached us through a common friend’s reference and told that they need to improve the chemistry of an advanced intermediate for their next campaign. At that time they are planning to make 15kg of that intermediate and purchased 50kg of starting raw material for $250,000. They also put five FTEs at a CRO for 5 months to optimize the remaining 5 steps wherein they are using LAH, Sodium azide, palladium catalyst and a column chromatography. We requested the customer not to purchase the 50kg raw material, and offered that we will make the 15kg for the price of raw material through a new route in less than three months time. You pay us only after we deliver 15 kg material. The customer didn’t want to take a chance with their timeline as they didn’t work with us before but requested us to develop the chemistry. In 7 weeks time, we developed a very simple four step route for their advanced intermediate and made 50g. We used very inexpensive and readily available starting material. Our route gave three solid intermediates and completely eliminated chromatographic purifications.

One of my former colleague introduced an academic group in midwest and brought us a medchem project requiring synthesis of 65 challenging polyene compounds on 100mg scale. We designed synthetic routes and successfully prepared 60 compounds in a 15 month time.

UNQUOTE…………

The man behind Seeni labs is Dr.Sreenivasa Reddy Mundla

Sreenivasa Reddy

Dr. Sreenivasa Reddy Mundla

Managing Director at Sreeni Labs Private Limited

Sreeni Labs Private Limited

Road No:12, Plot No:24,25,26

IDA, Nacharam
Hyderabad, 500076
Telangana State, India

Links

LINKEDIN https://in.linkedin.com/in/sreenivasa-reddy-10b5876

FACEBOOK https://www.facebook.com/sreenivasa.mundla

RESEARCHGATE https://www.researchgate.net/profile/Sreenivasa_Mundla/info

EMAIL mundlasr@hotmail.com, Info@sreenilabs.com, Sreeni@sreenilabs.com

Phone :+91-9866092626, India

Dr. Sreenivasa Mundla Reddy

Dr. M. Sreenivasa Reddy obtained Ph.D from University of Hyderabad under the direction Prof Professor Goverdhan Mehta in 1992. From 1992-1994, he was a post doctoral fellow at University of Wisconsin in Professor Jame Cook’s lab. From 1994 to 2000, worked at Chemical process R&D at Procter & Gamble Pharmaceuticals (P&G). From 2001 to 2007 worked at Global Chemical Process R&D at Eli Lilly and Company in Indianapolis.

In 2007 resigned to his job and founded Sreeni Labs based in Hyderabad, Telangana, India and started working with various global customers and solving various challenging synthesis problems.
The main strength of Sreeni Labs is in the design, development of a novel chemical route and its development into a robust process followed by production of quality product from 100 grams to 100’s of kg scale.

They have helped number of customers by successfully developing highly economical simple chemistry routes to number of products that were made by Suzuki coupling. they are able to shorten the route by drastically reducing number of steps, avoiding use of palladium & expensive ligands. they always use readily available or easy to prepare starting materials in their design of synthetic routes.

Sreeni Labs is Looking for any potential opportunities where people need development of cost effective scalable routes followed by quick scale up to produce quality products in the pharmaceutical & specialty chemicals area. They have flexible business model that will be in sink with customers. One can test their abilities & capabilities by giving PO based projects

Experience

Founder & Managing Director

Sreeni Labs Private Limited

August 2007 – Present (8 years 11 months)

Sreeni Labs Profile

View On SlideShare

Principal Research Scientist

Eli Lilly and Company

March 2001 – August 2007 (6 years 6 months)

Senior Research Scientist

Procter & Gamble

July 1994 – February 2001 (6 years 8 months)

Education

University of Wisconsin-Milwaukee

PDF, Synthetic Organic Chemistry

1992 – 1994

University of Hyderabad

Doctor of Philosophy (Ph.D.),

1986 – 1992

Hari Krishna Santhapuram

With Sreenivasa Mundla, Narahara sastry, Ram Kishan Rao, Jagadeesh Bharatam, Jagadish Gunjur and Jagadish Bharatham.

PUBLICATIONS

Article: Expansion of First-in-Class Drug Candidates That Sequester Toxic All-Trans-Retinal and Prevent Light-Induced Retinal Degeneration

Jianye Zhang · Zhiqian Dong · Sreenivasa Reddy Mundla · X Eric Hu · William Seibel ·Ruben Papoian · Krzysztof Palczewski · Marcin Golczak

Article: ChemInform Abstract: Regioselective Synthesis of 4Halo ortho-Dinitrobenzene Derivative

Sreenivasa Mundla

Aug 2010 · ChemInform

Article: Optimization of a Dihydropyrrolopyrazole Series of Transforming Growth Factor-β Type I Receptor Kinase Domain Inhibitors: Discovery of an Orally Bioavailable Transforming Growth Factor-β Receptor Type I Inhibitor as Antitumor Agent

Hong-yu Li · William T. McMillen · Charles R. Heap · Denis J. McCann · Lei Yan · Robert M. Campbell · Sreenivasa R. Mundla · Chi-Hsin R. King · Elizabeth A. Dierks · Bryan D. Anderson · Karen S. Britt · Karen L. Huss

Apr 2008 · Journal of Medicinal Chemistry

Article: ChemInform Abstract: A Concise Synthesis of Quinazolinone TGF-β RI Inhibitor Through One-Pot Three-Component Suzuki—Miyaura/Etherification and Imidate—Amide Rearrangement Reactions

Hong-yu Li · Yan Wang · William T. McMillen · Arindam Chatterjee · John E. Toth ·Sreenivasa R. Mundla · Matthew Voss · Robert D. Boyer · J. Scott Sawyer

Feb 2008 · ChemInform

Article: ChemInform Abstract: A Concise Synthesis of Quinazolinone TGF-β RI Inhibitor Through One-Pot Three-Component Suzuki—Miyaura/Etherification and Imidate—Amide Rearrangement Reactions

Hong-yu Li · Yan Wang · William T. McMillen · Arindam Chatterjee · John E. Toth ·Sreenivasa R. Mundla · Matthew Voss · Robert D. Boyer · J. Scott Sawyer

Nov 2007 · Tetrahedron

Article: Dihydropyrrolopyrazole Transforming Growth Factor-β Type I Receptor Kinase Domain Inhibitors: A Novel Benzimidazole Series with Selectivity versus Transforming Growth Factor-β Type II Receptor Kinase and Mixed Lineage Kinase-7

Hong-yu Li · Yan Wang · Charles R Heap · Chi-Hsin R King · Sreenivasa R Mundla · Matthew Voss · David K Clawson · Lei Yan · Robert M Campbell · Bryan D Anderson · Jill R Wagner ·Karen Britt · Ku X Lu · William T McMillen · Jonathan M Yingling

Apr 2006 · Journal of Medicinal Chemistry

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Article: Studies on the Rh and Ir mediated tandem Pauson–Khand reaction. A new entry into the dicyclopenta[ a, d]cyclooctene ring system

Hui Cao · Sreenivasa R. Mundla · James M. Cook

Aug 2003 · Tetrahedron Letters

Article: ChemInform Abstract: A New Method for the Synthesis of 2,6-Dinitro and 2Halo6-nitrostyrenes

Sreenivasa R. Mundla

Nov 2000 · ChemInform

Article: ChemInform Abstract: A Novel Method for the Efficient Synthesis of 2-Arylamino-2-imidazolines

Sreenivasa R. Mundla · Larry J. Wilson · Sean R. Klopfenstein · William L. Seibel · Nick N. Nikolaides

Nov 2000 · ChemInform

Article: A new method for the synthesis of 2,6-dinitro and 2-halo-6-nitrostyrenes

Sreenivasa R Mundla

Aug 2000 · Tetrahedron Letters

Read full-text, Source

Article: A Novel Method for the Efficient Synthesis of 2-Arylamino-2-imidazolines

Sreenivasa R Mundla · Larry J Wilson · Sean R Klopfenstein · William L. Seibel · Nick N Nikolaides

Aug 2000 · Tetrahedron Letters

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Article: Regioselective Synthesis of 4-Halo ortho-Dinitrobenzene Derivatives

Sreenivasa R Mundla

Jun 2000 · Tetrahedron Letters

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Article: Synthesis and Evaluation of Analogues of the Partial Agonist 6-(Propyloxy)-4-(methoxymethyl)-β-carboline-3-carboxylic Acid Ethyl Ester (6-PBC) and the Full Agonist 6-(Benzyloxy)-4-(methoxymethyl)-β- carboline-3-carboxylic Acid Ethyl Ester (Zk 93423) at Wild Type and Recombinant GABA A Receptors

Eric D. Cox · Hernando Diaz-Arauzo · Qi Huang · Mundla S. Reddy · Chunrong Ma · Brad Harris · Ruth McKernan · Phil Skolnick · James M. Cook

Aug 1998 · Journal of Medicinal Chemistry

Read at

[LINK]

Patents by Inventor Dr. Sreenivasa Reddy Mundla

TGF-? inhibitors

Patent number: 7872020

Abstract: The present invention provides crystalline 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl)-5,6-dihydro -4H-pyrrolo[1,2-b]pyrazole monohydrate.

Type: Grant

Filed: June 29, 2006

Date of Patent: January 18, 2011

Assignee: Eli Lilly and Company

Inventor: Sreenivasa Reddy Mundla
TGF-BETA INHIBITORS

Publication number: 20100120854

Abstract: The present invention provides crystalline 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl)-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole monohydrate.

Type: Application

Filed: June 29, 2006

Publication date: May 13, 2010

Applicant: ELI LILLY AND COMPANY

Inventor: Sreenivasa Reddy Mundla
Process for making 2-amino-2-imidazoline, guanidine and 2-amino-3,4,5,6-tetrahydropyrimidine derivatives

Patent number: 6066740

Abstract: The present invention provides a process for making 2-amino-2-imidazoline, guanidine, and 2-amino-3,4,5,6-tetrahydroyrimidine derivatives by preparing the corresponding activated 2-thio-subsituted-2-derivative in a two-step, one-pot procedure and by further reacting yields this isolated derivative with the appropriate amine or its salts in the presence of a proton source. The present process allows for the preparation of 2-amino-2-imidazolines, quanidines, and 2-amino-3,4,5,6-tetrahydropyrimidines under reaction conditions that eliminate the need for lengthy, costly, or multiple low yielding steps, and highly toxic reactants. This process allows for improved yields and product purity and provides additional synthetic flexibility.

Type: Grant

Filed: November 25, 1997

Date of Patent: May 23, 2000

Assignee: The Procter & Gamble Company

Inventors: Michael Selden Godlewski, Sean Rees Klopfenstein, Sreenivasa Reddy Mundla, William Lee Seibel, Randy Stuart Muth

TGF-β inhibitors

US 7872020 B2

Sreenivasa Reddy Mundla

The present invention provides 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl) -5,6-dihydro-4H-pyrrolo[1,2-b]pyrazole monohydrate, i.e., Formula I.

EXAMPLE 1 Preparation of 2-(6-methyl-pyridin-2-yl)-3-[6-amido-quinolin-4-yl-5,6-dihydro-4H -pyrrolo[1,2-b]pyrazole monohydrate

Galunisertib

¹H NMR (CDCl₃): δ=9.0 ppm (d, 4.4 Hz, 1H); 8.23-8.19 ppm (m, 2H); 8.315 ppm (dd, 1.9 Hz, 8.9 Hz, 1H); 7.455 ppm (d, 4.4 Hz, 1H); 7.364 ppm (t, 7.7 Hz, 1H); 7.086 ppm (d, 8.0 Hz, 1H); 6.969 ppm (d, 7.7 Hz, 1H); 6.022 ppm (m, 1H); 5.497 ppm (m, 1H); 4.419 ppm (t, 7.3 Hz, 2H); 2.999 ppm (m, 2H); 2.770 ppm (p, 7.2 Hz, 7.4 Hz, 2H); 2.306 ppm (s, 3H); 1.817 ppm (m, 2H). MS ES+: 370.2; Exact: 369.16

ABOVE MOLECULE IS

https://newdrugapprovals.org/2016/05/04/galunisertib/

Galunisertib

A TGF-beta receptor type-1 inhibitor potentially for the treatment of myelodysplastic syndrome (MDS) and solid tumours.

LY-2157299

CAS No.700874-72-2

READ MY PRESENTATION ON

Accelerating Generic Approvals, see how you can accelerate your drug development programme

Accelerating Generic Approvals by Dr Anthony Crasto

Accelerating Generic Approvals by Dr Anthony Crasto from Anthony Melvin Crasto Ph.D

KEYWORDS Sreenivasa Mundla Reddy, Managing Director, Sreeni Labs Private Limited, Hyderabad, Telangana, India, new, economical, scalable routes, early clinical drug development stages, Custom synthesis, custom manufacturing, drug discovery, PHASE 1, PHASE 2, PHASE 3, API, drugs, medicines

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Specific Stereoisomeric Conformations Determine the Drug Potency of Cladosporin Scaffold against Malarial Parasite

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May 272018

Specific Stereoisomeric Conformations Determine the Drug Potency of Cladosporin Scaffold against Malarial Parasite

https://pubs.acs.org/doi/abs/10.1021/acs.jmedchem.8b00565

Pronay Das, Palak Babbar, Nipun Malhotra, Manmohan Sharma, Gorakhnath R Jachak, Rajesh G. Gonnade, Dhanasekaran Shanmugam, Karl Harlos, Manickam Yogavel, amit sharma, and D. Srinivasa Reddy

Pronay Das†ab, Palak Babbar†c, Nipun Malhotra†c, Manmohan Sharmac , Goraknath R. Jachakab , Rajesh G. Gonnadebd, Dhanasekaran Shanmugambe, Karl Harlosf , Manickam Yogavelc , Amit Sharmac *, and D. Srinivasa Reddyab* †All three have contributed equally to this work.

aOrganic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India

b Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India

cMolecular Medicine Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi 110067, India dCenter for Material Characterization, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India

e Biochemical Sciences Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411008, India

fDivision of Structural Biology, Welcome Trust Centre for Human Genetics, The Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, UK

J. Med. Chem., Just Accepted Manuscript

DOI: 10.1021/acs.jmedchem.8b00565

Publication Date (Web): May 21, 2018

The dependence of drug potency on diastereomeric configurations is a key facet. Using a novel general divergent synthetic route for a three-chiral centre anti-malarial natural product cladosporin, we built its complete library of stereoisomers (cladologs) and assessed their inhibitory potential using parasite-, enzyme- and structure-based assays.

We show that potency is manifest via tetrahyropyran ring conformations that are housed in the ribose binding pocket of parasite lysyl tRNA synthetase (KRS). Strikingly, drug potency between top and worst enantiomers varied 500-fold, and structures of KRS-cladolog complexes reveal that alterations at C3 and C10 are detrimental to drug potency where changes at C3 are sensed by rotameric flipping of Glutamate332.

Given that scores of anti-malarial and anti-infective drugs contain chiral centers, this work provides a new foundation for focusing on inhibitor stereochemistry as a facet of anti-microbial drug development.

Cladosporin (12) displays exquisite selectivity for the parasite lysyl-tRNA synthetase over human enzyme. This species specific selectivity of cladosporin has been previously described through comprehensive sequence alignment, where the residues val329 and ser346 seem to be sterically crucial for accommodating the methyl moiety of THP ring10. The structural features of compound 12 clearly indicate the presence of three stereocenters, and therefore 2n (n=3) i.e., eight stereoisomers are possible (Fig.1). Till date, only one asymmetric total synthesis of cladosporin13 has been achieved which was followed by another report of formal syntheses14. Here, we have developed a general chemical synthesis route to synthetically access all the eight possible stereoisomers of compound 12.

cladosporin (compound 12) (0.052 g) as a white solid with a yield of 54 %. Melting point: 171-173 °C; [α]25 D = -15.75 (c = 0.6, EtOH); IR υmax(film): cm-1 3416, 3022, 1656, 1218; 1H NMR (400 MHz, CDCl3): δ 11.06 (s, 1H), 7.47 (br. s., 1H), 6.29 (s, 1H), 6.16 (s, 1H), 4.68 (t, J = 9.8 Hz, 1H), 4.12 (s, 1H), 4.01 (s, 1H), 2.89 – 2.75 (m, 2H), 2.00 – 1.94 (m, 1H), 1.87 – 1.81 (m, 1H), 1.70 – 1.63 (m, 4H), 1.35 (d, J = 6.1 Hz, 2H), 1.23 (d, J = 6.7 Hz, 3H); 13C NMR (100 MHz, CDCl3): δ 169.9, 164.3, 163.1, 141.8, 106.7, 102.0, 101.5, 76.3, 68.0, 66.6, 39.3, 33.6, 30.9, 18.9, 18.1; HRMS calculated for C16H21O5 [M + H]+ 293.1384, observed 293.1379.

Dr. D. Srinivasa Reddy has been appointed as an editor of Bioorganic & Medicinl Chemistry Letters, Elsevier Publications. Congratulation Sir !

Click here for details. https://www.journals.elsevier.com/bioorganic-and-medicinal-chemistry-letters

The research interests of his group lie in issues related to application of oriented organic synthesis, in particular total synthesis of biologically active natural products, medicinal chemistry and crop protection. This team has been credited with having accomplished total synthesis of more than 25 natural products with impressive biological activities. “Some of our recent achievements include identification of potential leads, like antibiotic compound based on hunanamycin natural product for treating food infections, anti-diabetic molecule in collaboration with an industry partner and anti-TB compound using a strategy called ‘re-purposing of a drug scaffold’,” said Reddy.

A total of two awardees out of four were from CSIR institutes. In addition to Reddy, Rajan Shankarnarayanan, CSIR – CCMB, Hyderabad (basic sciences), also was conferred with the award. Vikram Mathews, CMC, Vellore (medical research) and Prof Ashish Suri, AIIMS, New Delhi (clinical research), were the others to receive the awards.

With more than 80 scientific publications and 35 patents, Reddy is one of the most prominent scientists in the city and has already been honoured with the Shanti Swarup Bhatnagar prize in chemical sciences. Reddy is also a nominated member of the scientific body of Indian Pharmacopoeia, government of India and was elected as a fellow of the Telangana and Maharashtra Academies of Sciences in addition to the National Academy of Sciences, India (NASI).

//////////CLADOSPORIN, NCL, CSIR, SRINIVASA REDDY, PUNE, MALARIA

What are the drugs of the future?

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May 032018

A cartoon representing how, in history, we are continuously faced with new scientific advancements that make us question what the future holds and whether what we currently have is still useful or should be replaced.

What are the drugs of the future?

Med. Chem. Commun., 2018, Advance Article
DOI: 10.1039/C8MD90019A, Opinion

Huy X. Ngo, Sylvie Garneau-Tsodikova
Are small molecules or biologics the drugs of the future?

What are the drugs of the future?

http://pubs.rsc.org/en/Content/ArticleLanding/2018/MD/C8MD90019A?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FMD+%28RSC+-+Med.+Chem.+Commun.+latest+articles%29#!divAbstract

Huy X. Ngo*^a and Sylvie Garneau-Tsodikova*^a

Author affiliations

* Corresponding authors

^a University of Kentucky, 789 South Limestone Street, Lexington, USA
E-mail: huy.ngo@uky.edu, sylviegtsodikova@uky.edu

Abstract

Are small molecules or biologics the drugs of the future? Small-molecule drugs have historically been the pillars of traditional medicine. However, recently, we seem to be amidst a scientific revolution with the rise of many FDA-approved biologic drugs. This opinion article looks at the current state of small molecules and biologics and assesses what the future holds for these two broad classes of drugs.

Are small molecules or biologics the drugs of the future? Let’s think about this… (Fig. 1). For many of us growing up in the 20th century, videotapes were fixtures of our childhoods. In the current entertainment industry, videotapes have completely become obsolete and been replaced by more complex and sophisticated Blu-ray Discs, which deliver ultra high-definition pictures and films to viewers. Technological change is inevitable in our society, which embraces innovations. Similarly, the pharmaceutical industry has been experiencing its own scientific revolution, as more and more novel biologic drugs continue to emerge. Are these biologics the Blu-ray Discs of the pharmaceutical industry? Will smallmolecule drugs fade into history like videotapes did? In an attempt to address these questions, we will compare and contrast small-molecule and biologic drugs to assess what roles they will serve in our healthcare system in the future

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1,2 Diaminocyclohexane from Synthesis with Catalysts Pvt Ltd

ANTHONY CRASTO, MANUFACTURING, Presentations, PROCESS, SYNTHESIS, Uncategorized Comments Off

Apr 302018

+91- 999-997-2051

info@synthesiswithcatalysts.com

Website

http://www.synthesiswithcatalysts.com/

bpk@synthesiswithcatalysts.com

Axay Parmar

Founder at Synthesis with Catalysts Pvt. Ltd, axayrp@gmail.com

Basu Agarwal and Dr Razi Abdi

shr@synthesiswithcatalysts.com, ba@synthesiswithcatalysts.com

Synthesis with Catalysts Pvt Ltd was founded with an aim to help aromatic chemical, essential oil, pharmaceutical, API manufacturers to develop new products, increase productivity and improve production methodologies.

We have an advanced research and development centre where we innovate new chemical processes and improve the existing ones and help our customers implement the same. We support our research with pilot production of the products.

We are also developing precious metal complexes, Catalysts, Legends etc.

We are continuously working to reset standards of purity with our products.

The team at Synthesis with Catalysts Pvt Ltd has an vast experience and well renowned scientists of India have found it suitable to continue their Research in our facilities. The team with Synthesis with Catalysts Pvt Ltd has presented countless number of research papers all across the world.

We have a world class lab with all advance analytical testing machines.

RESEARCH & DEVELOPMENT

Synthesis with Catalysts Pvt Ltd.’s strength lies in its state-of- the-art infrastructure and R&D capabilities. Innovative process development is the foundation of SWC’s success. Our team of highly qualified R&D experts in process of research and technology development work 24 hours for inventing new processes and Optimizing product development capabilities. Our main focus is developing innovative processes, which could help our partners in reducing their costs and production time. Our Scientists constantly work for cost-effective ways of developing products, ensuring better service for our clients.

Image result for axay parmar synthesis

////////////1,2 Diaminocyclohexane, Synthesis with Catalysts Pvt Ltd

ANTHONY M CRASTO GETS PHARMA EXCELLENCE AWARD AT THE GOLDEN GLOBE TIGER AWARDS 2018

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Apr 232018

Pic…. Shobha crasto, Lionel and Aishal collecting my award named The Golden Globe Tigers Awards 2018, for Excellence in Pharma, at kuala lumpur, Malaysia, 23 april 2018 at Pullman city centre hotel, Kuala lumpur, Malaysia. Dr Anthony could not travel as he is wheelchair bound and 90 percent paralysed

Image may contain: Anthony Melvin Crasto, sitting and outdoor

DR ANTHONY M CRASTO

The Golden Globe Tigers Award 2018 is the highest recognition amongst individual and organizations who have achieved the highest levels of standards and benchmark in numerous areas such as CSR, Pharma, Social Media & Digital Marketing, Education Leadership Award and so on. The award ceremony took place in Pullman Kuala Lumpur City Centre Hotel & Residences on the 23rd of April, where a number of respectable attendees were present not only from Malaysia but from many different parts of the world such as Iceland, Saudi Arabia, India, China, South Africa and such!

The Golden Globe Tigers Award not only aims to increase awareness on CSR practices but also continuously innovate practices towards sustainable development. It is organized by the founder of the World CSR Day, World Sustainability Congress and World Women Leadership Congress.

Dr. Anthony Melvin Crasto, graduated from Mumbai University, Completed his Ph.D from ICT, 1991, Mumbai, India, in the field of Organic Chemistry, Currently he is working with GLENMARK PHARMACEUTICALS LTD, Research Centre as a Principal Scientist, in Process Research at Mahape, Navi Mumbai, India, for the last 10 years, His total Industry experience is 30 +yrs with major Multinationals companies.

Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable Scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri , Dr T.V. Radhakrishnan and Dr B. K. Kulkarni, etc, He did Custom Synthesis for various multinationals in his career like BASF, Novartis, Sanofi, Pfizer etc., He has worked in Drug Discovery, Natural products, Bulk Drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, Pharma Plant, API plant etc, he is now helping millions, His friends call him worlddrugtracker.

His New Drug Approvals, All about drugs, Eurekamoments, Organic spectroscopy international, etc in Organic/ Medchem are some most read blogs. He has hands on experience in initiation and developing Novel routes for Drug molecules and implementing them on commercial scale over a 30 year tenure till date Feb’ 2018, Around 30 plus commercial products in his career. He has good knowledge of IPM, GMP, QbD, Regulatory aspects, Technology transfer, Manufacturing, Formulations, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc. He has several International patents published worldwide.

He suffered a one in a million disease in the form of a paralytic stroke/ Acute Transverse Mylitis in Dec’ 2007 and is 90 % paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, he has several million hits on Google, 60 Lakh plus views on dozen plus blogs, He makes himself available to all, contact him on +91 9323115463, email amcrasto@gmail.com, Twitter, @amcrasto

He is a prolific presenter and is invited to major conferences in Mumbai, where he can travel easily. He speaks at universities on topics of Drug discovery, Patents, Qbd, GMP, Tech transfer, polymorphism, Literature search tools, Computer programs and Topics of interest to Pharma Students.

His extraordinary skill on the Computers give him the edge to write/present his thoughts. He demonstrates them to students and professionals alike.

Notably he has 20 lakh plus views on New Drug Approvals Blog in 216 countries, This blog has 3.5 lakh viewers in USA alone.

AWARDS

“100 Most Impactful Health care Leaders Global listing”, conferred at Taj lands end, Mumbai, India on 14 Feb 2014 by World Health Wellness congress and awards

“Best Worlddrugtracker “ Award for lifetime acheivement in Pharma… 7 th July 2017 , The venue…Taj land ends, Bandra, Mumbai India

“Lifetime achievement award” WORLD HEALTH CONGRESS 2017 in Hyderabad, 22 aug 2017 at JNTUH KUKATPALLY. HYDERABAD, TELANGANA, INDIA,

” Lifetime Achievement Award”, at the The Middle East Healthcare Leadership Awards – 12th October, 2017 -The Address, Dubai Mall, Dubai…UAE……….Mohammed Bin Rashid Boulevard, Downtown Dubai – Dubai – United Arab Emirates

International award for Outstanding contribution in Pharma at World Health and wellness Congress award, 14th Feb, 2018, at Taj Lands ends, Bandra, Mumbai, India

Conferred very prestigious IDMA award for contribution to society in Pharma at INDIAN DRUGS ANNUAL DAY 2018 VMCC IITBombay Powai, Mumbai India 22 Feb 2018,I was Guest of honor at and was felicitated by president,Indian Drug manufacturers association (IDMA)

The Golden Globe Tigers Awards 2018, for Excellence in Pharma, at kuala lumpur, Malaysia, 23 april 2018 at Pullman hotel.

Biography

READ MY BIOGRAPHY……….http://scijourno.com/2017/01/09/dr-anthony-crasto/ Written by Mr. Amrit B. Karmarkar
Director, InClinition

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Hear Dr Vijay kirpalani speak on: Thursday 26th April 2018 along with ChemSpec India 2018 in Hall 1, NSE, Goregaon, Mumbai, India

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Apr 192018

Vijay Kirpalani

HEAR GREAT DR VIJAY KIRPALANI AT, SEE BELOW

Flow Chemistry Society – India, welcome you to a “free-to-attend” Conference on ” Advances in Chemical Process Technology 2018″ which is being held on: Thursday 26th April 2018 along with ChemSpec India 2018 in Hall 1, NSE, Goregaon, Mumbai, India

Chemspec India 2018, the country’s leading exhibition dedicated to Fine and Speciality Chemicals, takes place for the fourteenth time from 25-26 April 2018

To attend the conferences or know more please contact:
Mr. Kiran Iyer,
M: 91-98201-71374
E: kiran@chemicalweekly.com

//////////////////////#mumbai #conferences #flowchemistry #chemicalprocessing #howto #nse #VIJAYKIRPALANI

SOFOSBUVIR, NEW PATENT, WO 2018032356, Pharmaresources (Shanghai) Co Ltd

PATENTS, Uncategorized Comments Off

Mar 142018

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SOFOSBUVIR, NEW PATENT, WO 2018032356, Pharmaresources (Shanghai) Co Ltd

WO-2018032356, Pharmaresources (Shanghai) Co Ltd

CHEN, Ping; (CN).
PENG, Shaoping; (CN).
LI, Yinqiang; (CN).
LI, Dafeng; (CN).
DONG, Xuejun; (CN)

Process for the preparation of lactone derivatives and their intermediates are important precursors for the synthesis of anti-hepatitis C virus agents, including sofosbuvir . Represents a first filing from Pharmaresources (Shanghai) Co Ltd and the inventors on this API. Gilead Sciences , following its acquisition of Pharmasset , has developed and launched sofosbuvir, a pure chiral isomer of PSI-7851, a next-generation HCV uracil nucleotide analog polymerase inhibitor prodrug for once-daily oral use.

Hepatitis C virus (HCV) infection represents a global health thereat in need of more effective treatment options. The World Health Organization (WHO) estimates that 130-170 million of individuals worldwide have detectable antibodies to HCV and approximately 60-85％of this population develops into chronic disease, leading to liver cirrhosis (5-25％) and hepatocellular carcinoma (1-3％) and liver failure. While there were existing therapeutics including pegylated interferon- (Peg-IFN) and ribavirin (RBV) , they are suboptimal due to various adverse effects, intolerability, low efficacy and slow response in reducing the viral loads across the multiple genotypes (1-6) of HCV. Therefore, there is an urgent and enormous need to develop more effective and efficacious novel anti-HCV therapies.

During the past decade, there have been a variety of small molecule agents as direct-acting antivirals (DAAs) targeting HCV viral replication via action on both structural and nonstructural proteins (NS3-5) have been launched inmarket or in late-stage clinical development. Among the DAAs reported, Soforsbuvir (brand name Sovaldi) targeting NS5B protein from Gilead was approved by FDA in 2003 for HCV genotypes 2 and 3 (in combination with Ribavin) . In 2014, a combination of Sofosbuvir with viral NS5A inhibitor Ledipasvir (brand name Harvoni) was approved. This combination provides high cure rates in people infected with HCV genotype 1, the most common subtype in the US, Japan, and much of the Europe, without the use of interferon, and irrespective of prior treatment failure or the presence of cirrhosis. Compared to previous treatment, Sofosbuvir-based regimens provide a higher cure rate, fewer side effects, and a 2-4 fold reduced duration of therapy.

Sofosbuvir is a prodrug using the ProTide biotechnology strategy. It is metabolized to the active antiviral agent 2′-deoxy-2′-α-fluoro-β-C-methyluridine-5′-triphosphate. The triphosphate serves as a defective substrate for the NS5B protein, which is the viral RNA polymerase, thus acts as an inhibitor of viral RNA synthesis.

Due to the tremendous success in Sorosbuvir-based oral therapy, there remains a need for a more efficient method for making sofosbuvir-like anti-hepatitis C virus agents, including sofosbuvir and intermediates thereof. A variety of methods describing different synthetic approaches for substituted lactone (VI) shown below, a key intermediate for Sofosbuvir and its like anti-viral drugs have been published.

WO2008045419 reported a seven-step synthesis (Scheme 1) for the γ-lactone intermediate. When chiral glyceraldehyde used as the starting material, two new chiral centers were generated following Witting reaction and dihydoxylation. After cyclic sulfonate formed, the fluoro subsititution was introduced stereospecifically by a SN2 reaction with HF-Et3N. Lactonization was achieved under the acid conditions followed by hydroxy protecting step to give the desired intermediate. The main disadvantage of this approach is that considerable quantities of both solid and acidic liquid wastes were produced during the process which is very difficult to handle with (e.x. filtration) and/or contributes to the enviroment pollution upon disposal.

Scheme 1

In a similar process reported in CN105418547A (Scheme 2) , the Witting product was epoxidized followed by ring-opening fluorolation by HF-Et₃N or other fluoro-containing reagents, significant amount of regioisomer was observed which was difficult to remove from the oily mixture.

Scheme 2

US20080145901 reported an enzymetic approach to the γ-lactone intermediate (scheme 3) . Treatment of ethyl 2-fluoro-propinate with chiral glyceraldehyde to form the aldol adducts consisting the mixture of four disteroisomers. The disteroisomers were selectively hydrolyzed by enzyme and the major isomer was obtained. After lactonization and hydroxyl protecting, other two isomers were removed by recrystallization.

WO2008090046 reported a similar synthesis as described in Scheme 3.2-fluoro-propionic acid was converted to diffirent bulky ester or amide and reacted with chiral glyceraldehydes. The mixture of the disteroisomers were purified by recrystallization to obtain the pure isomer. By using the method described in Scheme 3, the γ-lactone can be scale up to kilogram quantities but the de value of the final product can not achieve desired level.

Scheme 3

In WO2014108525, WO2014056442 and CN105111169, diffirent auxiliaries were used in the Aldol Reaction to improve the disteroisomeric selectivity (Scheme 4) . The process was shortened to 3～4 steps and the de value was increase significantly.

Scheme 4

Examples

Example 1： preparation of 2-fluoropropanoyl chloride (3)

Chlorosulfonic acid (660 mL, 10 mol, 20 eq) was added to a solution of phthaloyl dichloride (1.4 L, 10 mol, 20 eq) and ethyl-2-fluoropropanoate (600 g, 5 mol) at room temperature. The solution was heated at 120 ℃ for 4 hs. 2- (R) -fluoropropanoyl chloride was distilled from the reaction mixture under reduced pressure and recovered as a colourless oil (320 g, 58.2％) . ¹H-NMR (CDCl₃， 400 MHz) ： δ 5.08 (dq, J ＝ 48.8, 6.8 Hz, 1 H) , 1.63 (dd, J ＝22.8, 6.8 Hz, 3 H) .

Example 2： preparation of (4R) -3- (2-fluoropropanoyl) -4-isopropyloxazolidin-2-one (4)

n-Butyl lithium (2.5 M in hexane, 30 mL, 75 mmol, 1.1 eq) was added to a solution of 4-(R) -4-isopropyl-2-oxazolidinone (8.8 g, 68.2 mmol, 1 eq) in dry THF (80 mL) at -50 ℃ under N₂ atomosphere. After 30 min, 2-fuoropropanoyl chloride (6.8 mL, 0.9 eq) was added, and the solution was stirred for 4 hs at -50 ℃. The reaction was then quenched with a saturated solution of NH₄Cl (50 mL) , extracted with MTBE (80 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure. The product was purified over silica (Hexane/EtOAc＝ 10/1) and recovered as a brown oil (9 g, 74.8％) . ¹H-NMR (CDCl₃, 400 MHz) : δ 6.00 (dm, J ＝ 49.2Hz, 1 H) , 4.27 -4.53 (m, 3 H) , 2.43 (dm, J ＝ 52.6 Hz, 1 H) , 1.63 (td, J ＝ 23.2Hz, 3 H) , 0.92 (dq, J ＝ 17.8 Hz, 6 H) .

[0206]

Example 3： preparation of (4S) -3- (2-fluoropropanoyl) -4-isopropyloxazolidin-2-one (5)

[0207]

n-Butyl lithium (2.5 M in hexane, 75 mL, 187 mmol, 1.1eq) was added to a solution of 4- (S) -4-isopropyl-2-oxazolidinone (22 g, 170 mmol, 1 eq) in dry THF (200 mL) at -50 ℃ under N₂ atomosphere. After 30 min 2-fuoropropanoyl chloride (17 mL, 153 mmol, 0.9 eq) was added, and the solution was stirred for 1 h at -50 ℃. After the starting material was completely consumed, the reaction was then quenched with a saturated solution of NH₄Cl (125 mL) , extracted with MTBE (200 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure. The product was purified over silica (hexane/EtOAc＝ 10/1) and recovered as a brown oil (34 g, 83.3％) . ¹H-NMR (CDCl₃, 400 MHz) : δ 5.93 (dm， J ＝ 48.8 Hz, 1 H) , 4.19 -4.17 (m, 3H) , 2.35 (dm, J ＝ 52.8 Hz , 1 H) , 1.55 (td, J ＝ 23.6 Hz, 3 H) , 0.85 (dq, J ＝ 18 Hz, 6 H) .

Example 4： preparation of (4R) -3- (2-fluoropropanoyl) -4-phenyloxazolidin-2-one (6)

n-Butyl lithium (2.5 M in hexane, 13.5 mL, 33.74 mmol, 1.1 eq) was added to a solution of (R) -4-phenyloxazolidin-2-one (5 g, 30.67 mmol, 1 eq) in dry THF (75 mL) at -50 ℃ under N₂ atomosphere. After 30 minutes, 2-fuoropropanoyl chloride (3.75 g, 33.74 mmol) was added, and the solution was stirred for 1 h at -50 ℃ to -60 ℃. The reaction was then quenched with a saturated solution of NH₄Cl, extracted with EtOAc, washed with NaHCO₃(sat) , brine and dried over MgSO₄. Solvents were removed under reduced pressure. The product was purified over silica (hexane /EtOAc) and recovered as a brown oil (4 g, 55％) . ¹H-NMR (CDCl₃, 400 MHz) : δ 7.35-7.21 (m, 5 H) , 5.99-5.84 (md, 1 H) , 5.42-5.33 (dd, 1 H) , 4.72 (dd, 1 H) , 4.31 (m, 1 H) , 1.50 (m, 3 H) .

Example 5： preparation of (4s) -3- (2-fluoropropanoyl) -4-phenyloxazolidin-2-one (7)

n-Butyl lithium (2.5 M in hexane, 67.5 mL, 169 mmol, 1.1 eq) was added to a solution of (s) -4-phenyloxazolidin-2-one (25 g, 153 mmol, 1 eq) in dry THF (375 mL) at -60 ℃ under N₂ atomosphere. After 30 min, 2-fuoropropanoyl chloride (18.7 g, 169 mmol) was added, and the solution was stirred for 1h at -50 ℃ to -60 ℃. The reaction was then quenched with a saturated solution of NH₄Cl, extracted with EtOAc, washed with NaHCO₃ (sat) , brine and dried over MgSO₄. Solvents were removed under reduced pressure. The product was purified over silica (hexane /EtOAc) and recovered as a brown oil (16.5 g, 45.4％) . ¹H-NMR (CDCl₃, 400 MHz) : δ 7.36-7.20 (m, 5 H) , 5.95-5.80 (md, 1 H) , 5.42-5.30 (dd, 1 H) , 4.71 (dd, 1 H) , 4.30 (m, 1 H) , 1.51 (m, 3 H) .

Example 6： preparation of (4S) -4-benzyl-3- (2-fluoropropanoyl) oxazolidin-2-one (8)

n-Butyl lithium (2.5 M in hexane, 54.7 mL, 137 mmol, 1.1eq) was added to a solution of (S) -4-benzyloxazolidin-2-one (22 g, 124 mmol, 1eq) in dry THF (220 mL) at -60 ℃ under N₂ atomosphere. After stirring 30 min at -60 ℃, 2-fuoropropanoyl chloride (15.2 g, 137 mmol) was added dropwisely below -50 ℃ , after adding the solution was stirred for 1h at -50 ℃ to -60 ℃. The reaction was then quenched with a saturated solution of NH₄Cl, extracted with EtOAc, washed with NaHCO₃ (sat) , brine and dried over MgSO₄. Solvents were removed under reduced pressure. The product was purified over silica (hexane/EtOAc) and recovered as a brown oil (25.8 g, 82.7％) . ¹H-NMR(400 MHz, CDCl₃ ) ： δ 7.29-7.13 (m, 5 H) , 6.01-5.81 (qd, 1 H) , 4.71-4.58 (md, 1 H) , 4.29-4.04 (m, 2 H) , 3.32-3.16 (dd, 1 H) , 2.79-2.74 (m, 1 H) , 1.51 (m, 3 H) .

Example 7： preparation of (4R) -4-benzyl-3- (2-fluoropropanoyl) oxazolidin-2-one (9)

Use the procedure described in Example 6, (R) -4-benzyloxazolidin-2-one as the start material to give the desired compound (4R) -4-benzyl-3- (2-fluoropropanoyl) oxazolidin-2-one (yield: 85％) . ¹H-NMR (400 MHz, CDCl₃ ) ： δ 7.27 -7.12 (m, 5 H) , 6.00-5.83 (qd, 1 H) , 4.72-4.55 (md, 1 H) , 4.27-4.03 (m, 2 H) , 3.32 -3.16 (dd, 1 H) , 2.79 -2.72 (m, 1 H) , 1.53 (m, 3 H) .

[0221]

Example 8： preparation of (4R) -3- (2-fluoropropanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (10)

[0222]

[0223]

n-Butyl lithium (2.5 M in hexane, 48 mL) was added to a solution of (R) -4-isopropyl-5,5-diphenyloxazolidin-2-one (28.1 g) in dry THF (150 mL) at -65 ℃ under N₂ atomosphere. After stirring 30 min at -60 ℃, 2-fuoropropanoyl chloride (16.4 g, 1.5 eq) was added dropwisely below -60 ℃. After adding the solution was stirred for 2 h at -60 ℃. The reaction was then quenched with a saturated solution of NH₄Cl, extracted with EtOAc, washed with NaHCO₃ (sat) , brine and dried over MgSO₄. Solvents were removed under reduced pressure. The crude product was recrystalized in (DCM/PE) to give (4R) -3- (2-fluoropropanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (30 g, 85％) . ¹H-NMR (CDCl₃, 400 MHz) : δ 7.50 -7.26 (m, 10 H) , 5.89 (ddq, J ＝ 64.4, 49.3, 6.6 Hz, 1 H) , 5.37 (dd, J ＝ 70.8, 3.4 Hz, 1 H) , 2.00 (dd, J ＝ 7.3, 3.3 Hz, 1 H) , 1.70 (dd, J ＝ 23.4, 6.7 Hz, 1.5 H) , 1.12 (dd, J ＝ 23.8, 6.6 Hz, 1.5 H) , 0.83 (ddd, J ＝ 28.0, 16.7, 6.9 Hz, 6 H) .

[0224]

Example 9： preparation of (4S) -3- (2-fluoropropanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11)

[0225]

[0226]

Use the procedure described in Example 8 and (S) -4-isopropyl-5, 5-diphenyloxazolidin-2-one as the start material to give the desired compound (4S) -3- (2-fluoropropanoyl) -4-isopropyl- 5,5-diphenyl oxazolidin-2-one (yield: 82％) . ¹H-NMR (CDCl₃, 400 MHz) : δ 7.51 -7.27 (m, 10 H) , 5.90 (ddq, J ＝ 64.4, 49.3, 6.6 Hz, 1 H) , 5.38 (dd, J ＝ 70.8, 3.4 Hz, 1H) , 2.01 (dd, J ＝ 7.3, 3.3 Hz, 1 H) , 1.71 (dd, J ＝ 23.4, 6.7 Hz, 1.5 H) , 1.13 (dd, J ＝ 23.8, 6.6 Hz, 1.5 H) , 0.84 (ddd, J ＝ 28.0, 16.7, 6.9 Hz, 6 H) .

[0227]

Example 10： preparation of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12)

[0228]

[0229]

Method A: TiCl₄ (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4R) -3- (2-fluoropropanoy l ) -4-isopropyloxazolidin-2-one (4) (10 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N₂ atomosphere. After 10 min, diisopropylethyl amine (10.3 mL, 1.26 eq) was added and the solution was stirred for 2 hs at-78 ℃, then the second batch of TiCl₄ (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added. After 10 min, acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (10.2 g, yield: 80％, purity: 97.2％) . ¹H-NMR (400 MHz, CDCl₃) ： δ 5.89 (dddd, J ＝ 17.1, 10.5, 6.5, 0.8 Hz, 1 H) , 5.42 (d, J ＝17.2 Hz, 1 H) , 5.30 (d, J ＝ 10.1 Hz, 1 H) , 4.68 (dd, J ＝ 14.8, 6.5 Hz, 1 H) , 4.44 (d, J ＝ 4.0 Hz, 1 H) , 4.32 (t, J ＝ 8.5 Hz, 1 H) , 4.24 (dd, J ＝ 9.1, 3.4 Hz, 1 H) , 3.61 (d, J ＝ 6.5 Hz, 1 H) , 2.37 (dd, J ＝ 7.0, 4.1 Hz, 1 H) , 1.73 (s, 1.5 H) , 1.67 (s, 1.5 H) , 0.92 (ddd, J ＝ 7.8, 5.6, 2.4 Hz, 6 H) ； ¹⁹F-NMR (400 MHz, CDCl₃) : -158.3 ppm.

[0230]

Method B: TiCl₄ (1 M in DCM, 50 mL, 50mmol, 1.1 eq) was added to a solution of (4R) -3- (2-fluoropropanoy l ) -4-isopropyloxazolidin-2-one (10 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N₂ atomosphere. After 10 min, (-) -spartein (14.5 g, 1.26 eq) was added and the solution was stirred for 2 hs at-78 ℃, then the second batch of TiCl₄ (1 M in DCM, 50 mL, 50 mmol, 1.1eq) was added. After 10 min, acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with NH₄Cl (sat 50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (9.4 g, yield: 75％, purity: 96.5％) .

[0231]

Example 11： preparation of (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (13)

[0232]

[0233]

TiCl₄ (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoropropanoy l ) -4-isopropyloxazolidin-2-one (4) (10 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N₂ atomosphere. After 10 min, diisopropylethyl amine (15.9 g, 2.5 eq) was added and the solution was stirred for 2 hs at-78 ℃. Then acrylaldehyde (7 mL, 2eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (10.4 g, yield: 83％, purity: 92.8％) . ¹H-NMR (400 MHz, CDCl₃) ： δ 5.92 (d， J ＝ 1.1 Hz， 1 H) ， 5.44 (d, J ＝ 17.2 Hz, 1 H) , 5.34 -5.28 (m, 1 H) , 4.73 (dd, J ＝ 13.9, 6.2 Hz, 1 H) , 4.43 (m, 1 H) , 4.37 -4.30 (m, 1H) , 4.27 -4.21 (m, 1 H) , 2.43 -2.31 (m, 1H) , 1.77 (s, 1.5 H) , 1.71 (s, 1.5 H) , 0.91 (dd, J ＝ 12.1, 7.0 Hz, 6 H) ； ¹⁹F-NMR (400 MHz, CDCl₃) ： δ -159.1ppm.

[0234]

Example 12： preparation of (S) -4-benzyl-3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) oxazolidin-2-one

[0235]

[0236]

TiCl₄ (1 M in DCM, 50 mL, 50mmol, 1.1 eq) was added to a solution of (4S) -4-benzyl-3-(2-fluoro propanoyl) oxazolidin-2-one (8) (12.3 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N₂ atomosphere. After 10 min, TMEDA (15.9 g, 2.5 eq) was added and the solution was stirred for 2 hs at -78 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (50 mL) . The products were extracted into DCM (20 mL*2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (13 g, yield: 86％, purity: 91.5％) . ¹H-NMR (400 MHz, CDCl₃) ： δ 7.38 -7.27 (m, 3 H) , 7.22 (d, J ＝ 6.8 Hz, 2 H) , 5.96 (dddd, J ＝ 17.0, 10.5, 6.2, 1.2 Hz, 1 H) , 5.47 (d, J ＝ 17.2 Hz, 1 H) , 5.35 (d, J ＝ 10.5 Hz, 1 H) , 4.75 (dd, J ＝ 13.9, 6.2 Hz, 1 H) , 4.66 (td, J ＝ 7.1, 3.6 Hz, 1 H) , 4.23 (dd, J ＝ 16.3, 5.0 Hz, 2 H) , 3.33 (dd, J ＝ 13.3, 3.3 Hz, 1 H) , 2.76 (dd, J ＝13.3, 10.0 Hz, 1 H) , 1.81 (s, 1.5 H) , 1.76 (s, 1.5 H) ； ¹⁹F-NMR (400 MHz, CDCl₃) ： δ -158.47 ppm.

[0237]

Example 13： preparation of (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-one

[0238]

[0239]

TiCl₄ (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoropropanoyl) -4-phenyloxazolidin-2-one (7) (11.6 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N₂ atomosphere. After 10 min, Et₃N (12.5 g, 2.5 eq) was added and the solution was stirred for 2 hs at-78 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (12 g, yield: 83％, purity: 90.5％) . ¹H-NMR (400 MHz, CDCl₃) : δ 7.43 -7.30 (m, 5 H) , 5.81 (dddd, J ＝ 17.0, 10.5, 6.3, 1.1 Hz, 1 H) , 5.46 (dd, J ＝ 8.4, 5.1 Hz, 1 H) , 5.37 (dt, J ＝ 17.2, 1.2 Hz, 1 H) , 5.23 (d, J ＝ 10.4 Hz, 1 H) , 4.74 (t, J ＝ 8.7 Hz, 1 H) , 4.64 (dd, J ＝ 13.5, 6.3 Hz, 1 H) , 4.31 (dd, J ＝ 8.9, 5.2 Hz, 1 H) , 1.60 (s, 1.5H) , 1.55 (s, 1.5 H) ； ¹⁹F-NMR (400 MHz, CDCl₃) ： δ -158.47 ppm.

[0240]

Example 14： preparation of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-one

[0241]

[0242]

TiCl₄ (1 M in DCM, 50 mL, 50mmol, 1.1 eq) was added to a solution of (4R) -3- (2-fluoro propan oyl) -4-phenyloxazolidin-2-one (6) (11.6 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N₂ atomosphere. After 10 min, DIPEA (15.9 g, 2.5 eq) was added and the solution was stirred for 2 hs at-78 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78℃. Then the reaction was quenched with a saturated solution of NH₄Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (11.1 g, yield: 77％, purity: 91.5％) . ¹H-NMR (400 MHz, CDCl₃) : δ 7.44 -7.29 (m, 5 H) , 5.74 -5.63 (m, 1 H) , 5.48 (dd, J ＝ 8.4, 5.3 Hz, 1 H) , 5.35 -5.26 (m, 1 H) , 5.15 (d, J ＝ 10.5 Hz, 1 H) , 4.73 (t, 1 H) , 4.52 (dd, J ＝ 14.8, 6.2 Hz, 1 H) , 4.28 (dd, J ＝ 8.9, 5.3 Hz, 1 H) , 1.68 (s, 1.5 H) , 1.63 (s, 1.5 H) ； ¹⁹F-NMR (400 MHz, CDCl₃) ： δ -161.93 ppm.

[0243]

Example 15： preparation of (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one

[0244]

[0245]

Method 1: LiHMDS (1 M in THF, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry THF (100 mL) at -20 ℃ under N₂ atomosphere. After 1.5 hs, acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -20 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (50 mL) . The products were extracted into EA (50 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the crude product was used directly in the next step. m/z (ES+) : 412 [M+H] +.

[0246]

Method 2: (n-Bu) ₂BOTf (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry DCM (100 mL) at 0 ℃ under N₂ atomosphere. After 15 min, 2, 6-lutidine (10.5g, 2eq) was added and the solution was stirred for 2 hs at 0 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at 0 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (100 mL) . The products were extracted into DCM (40 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the crude product was used directly in the next step (17.82 g, yield: 88％ (Internal standard yield) .

[0247]

Method 3: (n-Bu) ₂BOTf (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry DCM (100 mL) at 0 ℃ under N₂ atomosphere. After 15 min, DIPEA (13 g, 2 eq) was added and the solution was stirred for 2 hs at 0 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at 0 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (100 mL) . The products were extracted into EA (50 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the crude product was used directly in the next step (16.2 g, yield: 80％ (Internal standard yield ) .

[0248]

Method 4: (C₆H₁₂) ₂BOTf (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry DCM (100 mL) at 0 ℃ under N₂ atomosphere. After 15 min, 2, 6-lutidine (10.5 g, 2 eq) was added and the solution was stirred for 2 hs at 0 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at 0 ℃. Then the reaction was quenched with a saturated solution of NH₄Cl (100 mL) . The products were extracted into DCM (50 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed under reduced pressure and the crude product was used directly in the next step (14.6 g, yield: 80％ (Internal standard yield ) .

[0249]

Example 16： preparation of (3R, 4R, 5R) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyl dihydro furan-2 (3H) -one

[0250]

Method 1:

[0251]

[0252]

N-Bromosuccinimide (19.6 g, 1.1 eq) was added portionwisely to a solution of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in DME/H₂O (4: 1, 130ml) at -5 ℃, and stirred for 2 hs . After the reaction was complete, NaHCO₃ (sat, 20 mL) was added and stirred for 0.5 h at rt. The mixture were extracted by DCM (50 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed, the residue dissolved by MTBE (1V) , the solid was filtered off to recover the auxiliary, the filtrate was concentrated to dryness to obtained the (3R, 4R, 5R) -5- (bromomethyl) -3-fluoro-4-hydroxy-3-methyldihydrofuran-2 (3H) -one (18a) . ¹H-NMR (400 MHz, CDCl₃) : δ 4.62 -4.53 (m, 1 H) , 4.37 (dd, J ＝ 3.0, 1.9 Hz, 1 H) , 3.73 (dd, J ＝ 10.1, 8.7 Hz, 1 H) , 3.60 (ddd, J ＝ 10.1, 5.8, 1.9 Hz, 1 H) , 2.59 (dd, J ＝ 2.5, 1.7 Hz, 1 H) , 1.67 (d, J ＝ 22.7 Hz, 3 H) ； ¹⁹F-NMR (400 MHz, CDCl₃) ： δ -172.248 ppm.

[0253]

Alternative Method 1a: Br₂ (17.6 g, 1.1 eq) was added portionwisely to a solution of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in MeCN/H₂O (4: 1, 130 mL) between -5 ℃ to -10 ℃ and stirred for 2 hs . After the reaction was complete, Na₂S₂O₃ (10％, 20 ml) was added and stirred for 0.5 h at rt then separated . The water phase was re-extracted by DCM (50 mL *2) , the combine organic phase was concentrated, dissolved by MTBE (1V) , the solid was filtered off to recover the auxiliary, the filtrate was concentrated to dryness to used in the next step.

[0254]

Alternative Method 1b: N-chlorosuccinimide (13.3 g, 1.1 eq) was added portionwisely to a solution of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in 100ml CH3CN at -5 ℃, and stirred for 2 hs . After the reaction was complete, NaHCO₃ (sat, 20 mL) was added and stirred for 0.5 h at rt. The mixture were extracted by DCM (50 mL *2) , washed with brine and dried over MgSO₄. Solvents were removed, the residue dissolved by MTBE (1V) , the solid was filtered off to recover the auxiliary, the filtrate was concentrated to dryness to obtained the (3R, 4R, 5R) -5- (chloromethyl) -3-fluoro-4-hydroxy-3-methyldihydrofuran-2 (3H) -one (18b) , m/z (ES+) : 183 [M+H] +.

[0255]

The related lactone 18a or 18b (0.14eq) was dissolved in EtOH (104 mL) , then KOH (30％in H₂O, 50 mL) was added into, the result mixture was reflux for 4 hs. Then HCl (16.7 mL, 12 M) was added into the mixture and reflux for another 2 hs. The solvent was removed and the residue was recrystalized in toluene to give the desired compound as a white solid (yield: 80～85％) . m/z (ES+) : 165 [M+H] +. ¹H-NMR (400 MHz, MeOD) : δ 4.34 (ddd， J ＝ 8.0， 4.2， 2.3 Hz， 1 H) , 4.02 (ddd, J ＝ 17.6, 15.2, 5.1 Hz, 2 H) , 3.74 (dd, J ＝ 13.0, 4.2 Hz, 1 H) , 1.60 (s, 1.5 H) , 1.54 (s, 1.5 H) ； ¹⁹F-NMR (400 MHz, MeOD) : -172.47 ppm.

[0256]

Method 2:

[0257]

[0258]

Osmium tetroxide (OsO4) (0.1 equiv) was added in one portion to a stirring solution of the (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in acetone/water (8: 1 ratio) under nitrogen. After 5 min, NMO (N-methylmorpholine N-oxide, 60％by weight in water, 1.1 equiv) was added in one portion and stirred for 24 h. The resulting reaction mixture was concentrated under reduced pressure and immediately purified via column chromatography to obtain the desired lactone (3R, 4R, 5S) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyldihydrofuran-2 (3H) -one (21) , yield: 87％, m/z (ES+) : 165 [M+H] +.

[0259]

15.1 g (92.3 mmol) (3R, 4R, 5S) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyl dihydrofuran-2 (3H) -one (21) was dissolved in 25 mL pyridine and 11.1 g (96.9 mmol) methanesulfonyl chloride was slowly added dropwise at -25 degC. It was stirred for a day at -25 deg and a day at -10 deg. After adding 20 mL of ethyl acetate and 20 mL water, the solvent was removed on a rotary evaporator. After neutralization with dilute sodium hydrogen carbonate solution, the solvent was removed in vacuo again, the residue was digested with ethyl acetate, the eluate was dried with magnesium sulfate and concentrated in vacuo to dryness. Recrystallization from ethyl acetate/diethyl ether gave a colorless crystalline product ( (2S, 3R, 4R) -4-fluoro-3-hydroxy-4-methyl-5-oxotetrahydrofuran-2-yl) methyl methanesulfonate (18c) . Yield: 31 ％.

[0260]

33.8g of ( (2S, 3R, 4R) -4-fluoro-3-hydroxy-4-methyl-5-oxotetrahydrofuran-2-yl) methyl methanesulfonate was disslolved in EtOH (104 mL) , then KOH (16.8 g , 3 eq) in H₂O (52 mL) was added into, the result mixture was reflux for 4 hs. Then HCl (16.7 mL, 12 M) was added into, the mixture was reflux for another 2 hs. The solvent was removed and the residue was recrystalized in toluene to give the desired compound as a white solid (10.5 g, yield: 45％) .

[0261]

Alternative reagents and reactions to those disclosed above can also be employed. For example, 4-methylbenzene-1-sulfonyl chloride can be used instead of methanesulfonyl chloride. Moreover, primary alcohol can be converted to chloro or bromo by using Ph₃P/CCl4, PPh₃P/CBr₄, PPh₃/NCS, PPh₃/NBS, or PPh₃/C₂Cl₆ as a halogenation reagent. The desired product can be obtained in good yields using these reagents and reactions.

[0262]

Method 3: Using a method analogous to that described as hereinabove and (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methyl pent-4-enoyl) -4-isopropyloxazolidin-2-one (13) as starting material provides the desired compound 19 (yield: 63.2％)

[0263]

Method 4： Using a method analogous to that described as hereinabove and (S) -4-benzyl-3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) oxazolidin-2-one (14) as starting material provides the desired compound 19 (yield: 71.8％)

[0264]

Method 5： Using a method analogous to that described as hereinabove and (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-one (15) as the start material gives the desired compound 19 (yield: 65.7％)

[0265]

Method 6： Using a method analogous to that described as hereinabove and (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-oneas (16) starting material provides the desired compound 19 (yield: 59.5％)

[0266]

Method 7： Using a method analogous to that described as hereinabove and (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (17) as starting material gives the desired compound 19 (yield: 66.7％)

[0267]

Example 17: preparation of ( (3R, 4R) -3- (benzoyloxy) -4-fluoro-4-methyl-5-oxotetra hydro fur an-2-yl) methyl benzoate

[0268]

[0269]

(3R, 4R) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyldihydrofuran-2 (3H) -one (19) (25.4 g, 0.154 mol) obtained from example 3 was dissolved in 200 ml of THF. 4- (Dimethylamino) -pyridine (8.2 g, 0.066 mol) and triethylamine (35 g, 0.35 mol) were added and the reaction mixture was cooled to 0 ℃. Benzoyl chloride (46.0 g, 0.33 mol) was added, and the mixture was warmed to 35-40 ℃ in the course of 2 hs. Upon completion of the reaction, water (100 mL) was charged and the mixture was stirred for 30 min. Phases were separated and to the aqueous phase methyl-tert-butyl ether (100 mL) was added and the mixture was stirred for 30 min. Phases were separated and the organic phase was washed with saturated NaCl solution (100 mL) . The combined organic phases were dried over Na₂SO₄ (20 g) filtered and the filtrate was evaporated to dryness. The residue was taken up in iso-propanol (250 mL) and the mixture was warmed to 50 ℃ and stirred for 60 min, then cooled down to 0 ℃ and further stirred for 60 min. The solid was filtered and the wet cake was washed with i-propanol (50 mL) and then dried under vacuum. The title compound ( (3R, 4R) -3- (benzoyloxy) -4-fluoro-4-methyl-5-oxotetrahydrofuran-2-yl) methyl benzoate (47.5 g, 82.6 ％yield) was obtained. ‘H-NMR (CDCl₃, 400 MHz) : 8.10 (d, 7＝7.6 Hz, 2H) , 8.00 (d, 7＝7.6 Hz, 2H) , 7.66 (t, 7＝7.6 Hz, IH) , 7.59 (t, 7＝7.6 Hz, IH) , 7.50 (m, 2H) , 7.43 (m, 2H) , 5.53 (dd, 7＝17.6, 5.6 Hz, IH) , 5.02 (m, IH) , 4.77 (dd, 7＝12.8, 3.6 Hz, IH) , 4.62 (dd, 7＝12.8, 5.2 Hz, IH) , 1.77 (d, 7＝23.2 Hz, 3H) .

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