Second Revision of USP Chapter <1> Injections and Implanted Drug Products (Parenterals)-Product Quality Tests

regulatory Comments Off

Mar 172016

After the revision of the General Chapter on quality testing of sterile medicinal products in the US American Pharmacopoeia had already been announced last year in the USP 38-NF 33, the USP is planning a new revision. Read more about the revision of Chapter <1>.

http://www.gmp-compliance.org/enews_05240_Second-Revision-of-USP-Chapter–1–Injections-and-Implanted-Drug-Products–Parenterals–Product-Quality-Tests_15090,15160,15266,Z-PEM_n.html

Last year already, the revision of the General Chapter on quality testing of sterile medicinal products was initiated in the USP 38 NF 33. The targeted official date for coming into force was the 1st May 2016. Now, the USP has announced that because of some comments received, there will be a further revision. This is due to the USP’s intention to support in Chapter 1 both existing monographs as well as new monographs to be developed. The new scope should now be focussed again to avoid confusion. The publication is striven for March 2016 as well as the adoption of the changes in the USP 40 NF 35. Furthermore, USP has announced that also the contents of General Chapters <2> to <5> will be examined.

On the USP website you will find further details regarding the revision of Chapter <1>.

///////USP 38-NF 33, revision of Chapter <1>, quality testing of sterile medicinal products, monographs, USP, new revision

New FDA Guidance on Completeness Assessements for Type II API Drug Master Files

regulatory Comments Off

Mar 172016

Since 1st October 2012, special regulations have been applying to the US Type II Drug Master Files. This year in February, the FDA published a new Guidance for Industry. Read here what the DMF holder has to consider when submitting data about the API Drug Master File.

http://www.gmp-compliance.org/enews_05256_New-FDA-Guidance-on-Completeness-Assessements-for-Type-II-API-Drug-Master-Files_15328,15339,S-WKS_n.html

Since the coming into force of the “Generic Drug User Fee Act” (GDUFA) on 1st October 2012, special regulations have been applying to the submission to the FDA of a Drug Master Files for a pharmaceutical API (Type II DMF). The DMF holder must pay a one-time fee when authorising the reference of his/ her DMF in an application for a generic drug (Abbreviated New Drug Application, ANDA). Moreover, the DMF will undergo a completeness assessment through the FDA.

This year in February, the FDA published a Guidance for Industry entitled “Completeness Assessments for Type II API DMFs under GDUFA” which provides DMF holders with comprehensive information regarding the application for a Type II DMF. The document describes the criteria according to which the FDA performs a completeness assessment and which data are expected.

This completeness assessment does not replace the full scientific assessment to be executed at a later time. It serves to find out whether the data contained in the DMF are sufficient for the ANDA. In a completeness assessment, the following elements are examined:

Is the DMF active?
Has the fee been paid?
Has the DMF been previously reviewed?
Does the DMF pertain to a single API?
Does the DMF contain certain administrative information?
Does the DMF contain all the information necessary to enable a scientific review?
Is the DMF written in English?

The Guidance contains a checklist (Appendix 1) listing the criteria according to which the FDA performs the assessment. For the DMF holder, this list is helpful to check the completeness of his/ her data before submitting them to the FDA.

One essential element underlined in this Guidance is to pay the DMF fee in due time (at least 6 months prior to the submission of an ANDA). The FDA won’t continue to process the DMF as long as the fee hasn’t been paid. If the applicant of an ANDA references in his dossier a DMF for which a fee is due, the FDA will inform him. If the fee hasn’t been paid within 20 days after notification, the FDA will stop the further processing of the application.

When submitting a DMF, the form “FDA 3794″ (Generic Drug User Fee Cover Sheet) should be attached. It contains the minimum information required by the FDA to determine whether the DMF holder has satisfied his fee obligations.

After the successful completeness assessment of a DMF, a number will be attributed and posted on a publicly available API DMF list. The FDA has compiled all important information regarding DMFs Type I-V on the Drug Master File webpage. Here, you can also find the list of all active DMFs.

//////API Drug Master File, fda, type2

An Improved Process for the Preparation of Tenofovir Disoproxil Fumarate

MANUFACTURING, PROCESS, SYNTHESIS Comments Off

Mar 152016

VIREAD® (tenofovir disoproxil fumarate) Structural Formula Illustration

Tenofovir Disoproxil Fumarate

For full details see end of page

PAPER

The current three-step manufacturing route for the preparation of tenofovir disoproxil fumarate (1) was assessed and optimized leading to a higher yielding, simpler, and greener process. Key improvements in the process route include the refinement of the second stage through the replacement of the problematic magnesium tert-butoxide (MTB) with a 1:1 ratio of a Grignard reagent and tert-butanol. The development of a virtually solvent-free approach and the establishment of a workup and purification protocol which allows the isolation of a pure diethyl phosphonate ester (8) was achieved

see………….http://pubs.acs.org/doi/abs/10.1021/acs.oprd.5b00364

An Improved Process for the Preparation of Tenofovir Disoproxil Fumarate

Darren L. Riley^*^†^∥, David R. Walwyn^‡^∥, and Chris D. Edlin^§^∥

^† Department of Chemistry, Natural and Agricultural Sciences, University of Pretoria, 2 Lynnwood Road, Hatfield, 0002, Gauteng, South Africa

^‡ Department of Engineering and Technology Management, University of Pretoria, Pretoria, South Africa

^§ Pharmaceutical Manufacturing Technology Centre, University of Limerick, Limerick, V94 T9PX, Republic of Ireland

^∥ iThemba Pharmaceuticals, Modderfontein, 1645, Gauteng South Africa

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00364

Publication Date (Web): March 04, 2016

*E-mail: darren.riley@up.ac.za.

University of Pretoria

Department of Chemistry

Pretoria, South Africa

Department of Chemistry, Natural and Agricultural Sciences, University of Pretoria, 2 Lynnwood Road, Hatfield, 0002, Gauteng, South Africa

Map of Department of Chemistry, Natural and Agricultural Sciences, University of Pretoria, 2 Lynnwood Road, Hatfield, 0002, Gauteng, South Africa

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Tenofovir Disoproxil Fumarate

5-[[(1R)-2-(6-Amino-9H-purin-9-yl)-1-methylethoxy]methyl]-2,4,6,8-tetraoxa-5-phosphanonanedioic Acid 1,9-Bis(1-methylethyl) Ester 5-Oxide (2E)-2-Butenedioate; GS 4331-05; PMPA Prodrug; Tenofovir DF; Virea; Viread;

GILEAD-4331-300

201341-05-1 – free base, (Tenofovir Disoproxil

fumarate

202138-50-9

113-115°C (dec.)

Molecular Structure:
CAS No.:	202138-50-9
Name:	Tenofovir disoproxil fumarate

Formula:	C₁₉H₃₀N₅O₁₀P^.C₄H₄O₄
Molecular Weight:	635.51
Synonyms:	TDF;PMPA prodrug;Tenofovir Disoproxil Fumarate [USAN];9-((R)-2-((Bis(((isopropoxycarbonyl)oxy)methoxy)phosphinyl)methoxy)propyl)adenine, fumarate;201341-05-1;Bis(NeopentylOC)PMPA;Viread;GS 4331-05 (1:1 Fumarate salt);Viread (1:1 Fumarate salt);Truvada;Tenofovir DF;[[(2R)-1-(6-aminopurin-9-yl)propan-2-yl]oxymethyl-(propan-2-yloxycarbonyloxymethoxy)phosphoryl]oxymethyl propan-2-yl carbonate;

Usage
tyrosinase inhibitor used for skin lightening and anti-melasma

Usage
An acyclic phosphonate nucleotide analog and selective HIV-1 RT inhibitor

Usage
Acyclic phosphonate nucleotide analogue; reverse transcriptase inhibitor. Used as an anti-HIV agent. Antiviral.

Tenofovir disoproxil is an antiretroviral medication used to prevent and treat HIV/AIDS and to treat chronic hepatitis B.^[1] The active substance is tenofovir, while tenofovir disoproxil is a prodrug that is used because of its better absorption in the gut.

The drug is on the World Health Organization’s List of Essential Medicines, the most important medications needed in a basic health system.^[2] It is marketed by Gilead Sciences under the trade name Viread (as the fumarate, TDF).^[3] As of 2015 the cost for a typical month of medication in the United States is more than 200 USD.^[4]

Medical uses

HIV-1 infection: Tenofovir is indicated in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults and pediatric patients 2 years of age and older.^[5] This indication is based on analyses of plasma HIV-1 RNA levels and CD4 cell counts in controlled studies of tenofovir in treatment-naive and treatment-experienced adults.
Tenofovir is indicated for the treatment of chronic hepatitis B in adults and pediatric patients 12 years of age and older.^[5]^[6]

HIV risk reduction

A Cochrane review examined the use of tenofovir for prevention of HIV before exposure. It found that both tenofovir alone and the tenofovir/emtricitabine combination decreased the risk of contracting HIV.^[7]

The U. S. Centers for Disease Control and Prevention (CDC) conducted a study in partnership with the Thailand Ministry of Public Health to ascertain the effectiveness of providing people who inject drugs illicitly with daily doses of the antiretroviral drug tenofovir as a prevention measure. The results of the study were released in mid-June 2013 and revealed a 48.9%-reduced incidence of the virus among the group of subjects who received the drug, in comparison to the control group who received a placebo. The principal investigator of the study stated: “We now know that pre-exposure prophylaxis can be a potentially vital option for HIV prevention in people at very high risk for infection, whether through sexual transmission or injecting drug use.”^[8]

Adverse effects

The most common side effects associated with tenofovir include nausea, vomiting, diarrhea, and asthenia. Less frequent side effects include hepatotoxicity, abdominal pain, and flatulence.^[9] Tenofovir has also been implicated in causing renal toxicity, particularly at elevated concentrations.^[10]

Tenofovir can cause acute renal failure, Fanconi syndrome, proteinuria, or tubular necrosis.^{[citation needed]} These side effects are due to accumulation of the drug in proximal tubules.^{[citation needed]} Tenofovir can interact with didanosine by increasing didanosine’s concentration.^{[citation needed]} It also decreases the concentration of atazanavir sulfate.^{[citation needed]}

Mechanism of action

Tenofovir is a defective adenosine nucleotide that selectively interferes with the action of reverse transcriptase, but only weakly interferes with mammalian DNA polymerases α, β, and mitochondrial DNA polymerase γ.^[11] Tenofovir prevents the formation of the 5′ to 3′ phosphodiester linkage essential for DNA chain elongation. A phosphodiester bond cannot be formed because the tenofovir molecule lacks an —OH group on the 3′ carbon of its deoxyribose sugar.^[11] Once incorporated into a growing DNA strand, tenofovir causes premature termination of DNA transcription. The drug is classified as a nucleotide analogue reverse transcriptase inhibitor (NRTI), that inhibits reverse transcriptase.^[11] Reverse transcriptase is a crucial viral enzyme in retroviruses such as human immunodeficiency virus (HIV) and in hepatitis B virus infections.^[5]

History

Tenofovir was initially synthesized by Antonín Holý at the Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic in Prague. The patent^[12] filed by Holý in 1984 makes no mention of the potential use of the compound for the treatment of HIV infection, which had only been discovered one year earlier.

In 1985, De Clercq and Holý described the activity of PMPA against HIV in cell culture.^[13] Shortly thereafter, a collaboration with the biotechnology company Gilead Sciences led to the investigation of PMPA’s potential as a treatment for HIV infected patients. In 1997 researchers from Gilead and the University of California, San Francisco demonstrated that tenofovir exhibits anti-HIV effects in humans when dosed by subcutaneous injection.^[14]

The initial form of tenofovir used in these studies had limited potential for widespread use because it was not absorbed when administered orally. A medicinal chemistry team at Gilead developed a modified version of tenofovir, tenofovir disoproxil.^[15] This version of tenofovir is often referred to simply as “tenofovir”. In this version of the drug, the two negative charges of the tenofovir phosphonic acid group are masked, thus enhancing oral absorption.

Tenofovir disoproxil was approved by the U.S. FDA on October 26, 2001, for the treatment of HIV, and on August 11, 2008, for the treatment of chronic hepatitis B.^[16]^[17]

Drug forms

Tenofovir disoproxil is a prodrug form of tenofovir. It is also marketed under the brand name Reviro by Dr. Reddy’s Laboratories. Tenofovir is also available in a fixed-dose combination with emtricitabine in a product with the brand name Truvada for once-a-day dosing. Efavirenz/emtricitabine/tenofovir disoproxil (brand name Atripla) — a fixed-dose triple combination of tenofovir, emtricitabine, and efavirenz, was approved by the FDA on 12 July 2006 and is now available, providing a single daily dose for the treatment of HIV.

Therapeutic drug monitoring

Tenofovir may be measured in plasma by liquid chromatography. Such testing is useful for monitoring therapy and to prevent drug accumulation and toxicity in people with kidney or liver problems.^[18]^[19]^[20]

PATENT

http://www.google.com/patents/EP2545063A2?cl=en

Tenofovir Disoproxil is chemically known as 9-[-2-(R)-[[bis [[(isopropoxycarbonyl) oxy]methoxy] phosphinoyl]methoxy]propyl]-adenine, having the following structural formula-I.

Formula-I

Tenofovir is a highly potent antiviral agent, particularly for the therapy or prophylaxis of retroviral infections and belongs to a class of drugs called Nucleotide Reverse Transcriptase Inhibitors (NRTI) which blocks reverse transcriptase an enzyme crucial to viral production in HIV-infected people.

Tenofovir Disoproxil and its pharmaceutically acceptable salts were first disclosed in US 5,922,695. This patent discloses the preparation of Tenofovir Disoproxil by the esterification of Tenofovir with chloromethyl isopropyl carbonate using l-methyl-2- pyrrolidinone and triethylamine. In this patent Tenofovir Disoproxil is converted into its Fumarate salt without isolation. PCT Publication WO 2008007392 discloses process for the preparation of Tenofovir Disoproxil fumarate, wherein the isolated crystalline Tenofovir Disoproxil is converted into fumarate salt.

Tenofovir Disoproxil processes in the prior art are similar to process disclosed in product patent US 5,922,695. According to the prior art processes, Tenofovir Disoproxil fumarate obtained is having low yields and also show the presence of impurities such as dimers.

scheme- 1.

Tenofovir disoproxil chloromethyl isopropyl carbonate

Tenofovir disoproxil fumarate

Example 1 : Process for the preparation of Tenofovir Disoproxil fumarate

Toluene (500 ml) was added to the Tenofovir (100 gm) and stirred at room temperature. To this triethylamine (66.31 gm) was added, temperature was raised to 90° C and water was collected by azeotropic distillation at 110°C. Toluene was completely distilled under vacuum at same temperature. The reaction mixture was cooled to room temperature and to this a mixture of N-methyl pyrrolidine (300 gm), triethylamine (66.31 gm), Tetrabutyl ammonium bromide (52.8 gm) and trimethyl silyl chloride (17.8 gm) were added. The above reaction mixture was heated to 50-55 °C and was added slowly chloromethyl. isopropyl carbonate (CMIC) and maintained the reaction mixture at 50-55°C for 5 hrs. (Qualitative HPLC analysis shows about 85% product formation). The above reaction mixture was cooled to room temperature and filtered. The filtrate was added to DM water at 5-10°C and extract with dichloromethane. The combined dichloromethane layer was concentrated under vacuum and the crude was Co-distilled with cyclohexane and this crude was taken into isopropyl alcohol (1000 ml). To this fumaric acid (38 gm) was added and temperature was raised to 50° C. The reaction mixture was filtered and filtrate was cooled to 5-10° C. The obtained solid was filtered and washed with isopropyl alcohol. The compound was dried under vacuum to yield Tenofovir Disoproxil fumarate (140 gm).

Example-2 : Preparation of Tenofovir

N-methyl-2-pyrrolidone (25 gm) was taken along with toluene (150 gm) into a reaction vessel. l-(6-amino-purin-9-yl)-propan-2-ol (100 gm); toluene-4-sulfonic acid diethoxy phosphoryl methyl ester (200 gm) and magnesium ter-butoxide (71.2 gm) were also taken at’ 25-35°C. Temperature was raised to 74-75 °C and maintained for 5-6hrs. After completion of reaction, acetic acid (60 gm) was added and maintained for 1 hr. Later aq.HBr (332 gm) was taken and heated to 90-95 °C. After reaction completion, salts were filtered and filtrate was subjected to washings with water and extracted into methylene dichloride. Later pH was adjusted using CS lye below 10 °C. Tenofovir product was isolated using acetone.

Yield: 110 gm.

Example 3 : Preparation of Tenofovir disoproxil

(R)-9-[2-(phosphonomethoxy)propyl]adenine (25 gm), triethyl amine (25 ml) and cyclohexane (200 ml) were combined and heated to remove water and the solvent was distilled off under vacuum. The reaction mass was cooled to room temperature N-methyl pyrrolidinone (55 ml), triethyl amine (25 ml) and tetra butyl ammonium bromide(54 gms) were added to the reaction mixture. The reaction mass was heated to 50-60°C and chloromethyl isopropyl carbonate (65 gm) was added and maintained for 4-8 hrs at 50- 60°C and then cooled to 0°C. The reaction mass was diluted with chilled water or ice and precipitated solid product was filtered. The mother liquor was extracted with methylene chloride (150 ml). The methylene chloride layer was washed with water (200 ml). The filtered solid and the methylene chloride layer were combined and washed with water and the solvent was distilled under vacuum. Ethyl acetate was charged to the precipitated solid. The reaction mass was then cooled to 0-5 °C and maintained for 6 hrs. The solid was filtered and dried to produce Tenofovir disoproxil (45 gm).

CLIPS

The reaction of chloromethyl chloroformate (I) with isopropyl alcohol (II) by means of pyridine or triethylamine in ether gives the mixed carbonate (III), which is then condensed with (R)-PMPA (IV) by means of diisopropyl ethyl-amine in DMF.

US 5922695; WO 9804569

CLIP 2

1) The protection of isobutyl D-(+)-lactate (I) with dihydropyran (DHP)/HCl in DMF gives the tetrahydropyranyloxy derivative (II), which is reduced with bis(2-methoxyethoxy)aluminum hydride in refluxing ether/ toluene yielding 2(R)-(tetrahydropyranyloxy)-1-propanol (III). The tosylation of (III) with tosyl chloride as usual affords the expected tosylate (VI), which is condensed with adenine (V) by means of Cs2CO3 in hot DMF, affording 9-[2(R)-(tetrahydropyranyloxy)propyl]adenine (VI). The deprotection of (VI) with sulfuric acid affords 9-[2(R)-hydroxypropyl]adenine (VII), which is N-benzoylated with benzoyl chloride/chlorotrimethylsilane in pyridine to give the benzamide (VIII), which is condensed with tosyl-oxymethylphosphonic acid diisopropyl ester (IX) by means of NaH in DMF to yield 9-[2(R)-(diisopropoxyphosphorylmethoxy)propyl]adenine (X). Finally, this compound is hydrolyzed by means of bromotrimethylsilane in acetonotrile.

2) The reaction of the previously described (R)-2-(2-tetrahydropyranyloxy)-1-propanol (III) with benzyl bromide (XI) by means of NaH in DMF, followed by a treatment with Dowex 50X, gives 1-benzyloxy-2(R)-propanol (XII), which is condensed with tosyloxymethylphosphonic acid diisopropyl ester (IX) by means of NaH in THF, yielding 2-benzyloxy-1(R)-methylethoxymethylphosphonic acid diisopropyl ester (XIII). The hydrogenolysis of (XIII) over Pd/C in methanol affords 2-hydroxy-1(R)-methylethoxymethylphosphonic acid diisopropyl ester (XIV), which is tosylated with tosyl chloride/dimethyl-aminopyridine in pyridine to give the expected tosylate (XV). The condensation of (XV) with adenine (VI) by means of Cs2CO3 in hot DMF yields 9-[2(R)-(diisopropoxyphosphorylmethoxy)propyl]adenine (X), which is finally hydrolyzed as before.

3) The catalytic hydrogenation of (S)-glycidol (XVI) over Pd/C gives the (R)-1,2-propanediol (XVII), which is esterified with diethyl carbonate (XVIII)/NaOEt, yielding the cyclic carbonate (XIX). The reaction of (XIX) with adenine (V) by means of NaOH in DMF affords 9-[2(R)-hydroxypropyl]adenine (VII), which is condensed with tosyloxymethylphosphonic acid diethyl ester (XX) by means of lithium tert-butoxide in THF, giving 9-[2(R)-(diethoxyphosphorylmethoxy)propyl]adenine (XXI). Finally, this compound is hydrolyzed with bromotrimethylsilane as before. Compound (XX) is obtained by reaction of diethyl phosphite (XXII) with paraformaldehyde, yielding hydroxy- methylphosphonic acid diethyl ester (XXIII), which is finally tosylated as usual.

References

1 “Viread”. The American Society of Health-System Pharmacists. Retrieved 31 July 2015.
2
“WHO Model List of EssentialMedicines” (PDF). World Health Organization. October 2013. Retrieved 22 April 2014.
3
Emau P, Jiang Y, Agy MB, et al. (2006). “Post-exposure prophylaxis for SIV revisited: Animal model for HIV infection”. AIDS Res Ther 3: 29. doi:10.1186/1742-6405-3-29. PMC 1687192. PMID 17132170.
4
Hamilton, Richart (2015). Tarascon Pocket Pharmacopoeia 2015 Deluxe Lab-Coat Edition. Jones & Bartlett Learning. p. 66. ISBN 9781284057560.
5
Gilead Sciences, Inc. Prescribing Information. Revised: November 2012.
6
Guidelines for the prevention, care and treatment of persons with chronic hepatitis B infection, WHO, Publication details:Pages: 166 Publication date: March 2015 Languages: English ISBN 978 92 4 154905 9
7
Okwundu CI, Uthman OA, Okoromah CAN (2012). “Antiretroviral pre-exposure prophylaxis (PrEP) for preventing HIV in high-risk individuals”. Cochrane Database Syst Rev 7 (7): CD007189. doi:10.1002/14651858.CD007189.pub3. PMID 22786505.
8
Emma Bourke (14 June 2013). “Preventive drug could reduce HIV transmission among injecting drug users”. The Conversation Australia. The Conversation Media Group. Retrieved 17 June 2013.
9
USPDI. Thompson. 2005. pp. 2741–2.
10
“Viread Prescribing Guidelines” (PDF). U.S. Food and Drug Administration. March 2006. Archived from the original (PDF) on 2007-09-30. Retrieved 2007-02-12.
11
Drugbank: Tenofovir
12
“Patent US4808716 – 9-(phosponylmethoxyalkyl) adenines, the method of preparation and … – Google Patents”.
13
A US 4724233 A, De Clercq, Erik; Antonin Holy & Ivan Rosenberg, “Therapeutical application of phosphonylmethoxyalkyl adenines”, published 1985-04-25
14
Deeks SG, Barditch-Crovo P, Lietman PS, et al. (September 1998). “Safety, pharmacokinetics, and antiretroviral activity of intravenous 9-[2-(R)-(Phosphonomethoxy)propyl]adenine, a novel anti-human immunodeficiency virus (HIV) therapy, in HIV-infected adults”. Antimicrob. Agents Chemother. 42 (9): 2380–4. PMC 105837. PMID 9736567.
15
“Patent US5977089 – Antiviral phosphonomethoxy nucleotide analogs having increased oral … – Google Patents”.
16
FDA letter of approval (regarding treatment of hepatitis B)
17
FDA Clears Viread for Hepatitis B
18
Delahunty T, Bushman L, Robbins B, Fletcher CV (2009). “The simultaneous assay of tenofovir and emtricitabine in plasma using LC/MS/MS and isotopically labeled internal standards”. J. Chrom. B 877 (20–21): 1907–1914. doi:10.1016/j.jchromb.2009.05.029.
19
Kearney BP, Yale K, Shah J, Zhong L, Flaherty JF (2006). “Pharmacokinetics and dosing recommendations of tenofovir disoproxil fumarate in hepatic or renal impairment”. Clin. Pharmacokinet. 45 (11): 1115–24. doi:10.2165/00003088-200645110-00005. PMID 17048975.
20

R. Baselt, Disposition of Toxic Drugs and Chemicals in Man, 8th edition, Biomedical Publications, Foster City, California, 2008, pp. 1490–1492.

External links

Official Viread website

WO2008007392A2	Jul 11, 2007	Jan 17, 2008	Matrix Lab Ltd	Process for the preparation of tenofovir
US5922695	Jul 25, 1997	Jul 13, 1999	Gilead Sciences, Inc.	Antiviral phosphonomethyoxy nucleotide analogs having increased oral bioavarilability

WO2015051874A1	Sep 22, 2014	Apr 16, 2015	Zentiva, K.S.	An improved process for the preparation of tenofovir disoproxil and pharmaceutically acceptable salts thereof
CN103360425A *	Apr 1, 2012	Oct 23, 2013	安徽贝克联合制药有限公司	Synthesis method of tenofovir disoproxil and fumarate thereof
CN103374038A *	Apr 11, 2012	Oct 30, 2013	广州白云山制药股份有限公司广州白云山制药总厂	Preparation method of antiviral medicine
CN103848868A *	Dec 4, 2012	Jun 11, 2014	蚌埠丰原涂山制药有限公司	Method for preparing tenofovir
CN103848869A *	Dec 4, 2012	Jun 11, 2014	上海医药工业研究院	Method for preparing tenofovir
CN103980319A *	Apr 24, 2014	Aug 13, 2014	浙江外国语学院	Preparation method of tenofovir
CN103980319B *	Apr 24, 2014	Dec 2, 2015	浙江外国语学院	一种泰诺福韦的制备方法
EP2860185A1	Oct 9, 2013	Apr 15, 2015	Zentiva, k.s.	An improved process for the preparation of Tenofovir disoproxil and pharmaceutically acceptable salts thereof

The chemical name of tenofovir disoproxil fumarate is 9-[(R)-2[[bis[[(isopropoxycarbonyl)oxy]methoxy]phosphinyl]methoxy]propyl]adenine fumarate (1:1). It has a molecular formula of C₁₉H₃₀N₅O₁₀P • C₄H₄O₄ and a molecular weight of 635.52. It has the following structural formula:

VIREAD® (tenofovir disoproxil fumarate) Structural Formula Illustration

Tenofovir disoproxil fumarate is a white to off-white crystalline powder with a solubility of 13.4 mg/mL in distilled water at 25 °C. It has an octanol/phosphate buffer (pH 6.5) partition coefficient (log p) of 1.25 at 25 °C.

VIREAD is available as tablets or as an oral powder.

VIREAD tablets are for oral administration in strengths of 150, 200, 250, and 300 mg of tenofovir disoproxil fumarate, which are equivalent to 123, 163, 204 and 245 mg of tenofovir disoproxil, respectively. Each tablet contains the following inactive ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and pregelatinized starch. The 300 mg tablets are coated with Opadry II Y-3010671-A, which contains FD&C blue #2 aluminum lake, hypromellose 2910, lactose monohydrate, titanium dioxide, and triacetin. The 150, 200, and 250 mg tablets are coated with Opadry II 32K-18425, which contains hypromellose 2910, lactose monohydrate, titanium dioxide, and triacetin.

VIREAD oral powder is available for oral administration as white, taste-masked, coated granules containing 40 mg of tenofovir disoproxil fumarate per gram of oral powder, which is equivalent to 33 mg of tenofovir disoproxil. The oral powder contains the following inactive ingredients: mannitol, hydroxypropyl cellulose, ethylcellulose, and silicon dioxide.

enofovir disoproxil
Systematic (IUPAC) name

Bis{[(isopropoxycarbonyl)oxy]methyl} ({[(2R)-1-(6-amino-9H-purin-9-yl)-2-propanyl]oxy}methyl)phosphonate
Clinical data
Trade names	Viread
AHFS/Drugs.com	monograph
Pregnancy category	AU: B3 US: B (No risk in non-human studies)
Routes of administration	Oral (tablets)
Legal status
Legal status	AU: S4 (Prescription only) CA: ℞-only UK: POM (Prescription only) US: ℞-only
Pharmacokinetic data
Bioavailability	25%
Identifiers
CAS Number	201341-05-1
ATC code	J05AF07 (WHO)
PubChem	CID 5481350
ChemSpider	4587262
UNII	F4YU4LON7I
ChEBI	CHEBI:63717
NIAID ChemDB	080741
Chemical data
Formula	C₁₉H₃₀N₅O₁₀P
Molar mass	519.443 g/mol
SMILES [show]
InChI [show]

Tenofovir
Systematic (IUPAC) name

({[(2R)-1-(6-amino-9H-purin-9-yl)propan-2-yl]oxy}methyl)phosphonic acid
Clinical data
MedlinePlus	a602018
Routes of administration	In form of prodrugs
Pharmacokinetic data
Protein binding	< 1%
Biological half-life	17 hours
Excretion	Renal
Identifiers
CAS Number	147127-20-6
ATC code	None
PubChem	CID 464205
DrugBank	DB00300
ChemSpider	408154
UNII	99YXE507IL
KEGG	D06074
ChEBI	CHEBI:63625
ChEMBL	CHEMBL483
Synonyms	9-(2-Phosphonyl-methoxypropyly)adenine (PMPA)
Chemical data
Formula	C₉H₁₄N₅O₄P
Molar mass	287.213 g/mol

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Breaking the symmetry of dibenzoxazines: a paradigm to tailor the design of bio-based thermosets

spectroscopy, SYNTHESIS Comments Off

Mar 132016

Green Chem., 2016, Advance Article

DOI: 10.1039/C5GC03102H, Paper

L. Puchot, P. Verge, T. Fouquet, C. Vancaeyzeele, F. Vidal, Y. Habibi

Asymmetric di-benzoxazine monomers from naturally occurring phenolic compounds – cardanol and vanillin – were synthesized to obtain a processable and self-supported bio-thermoset with valuable properties. Such strategy constitutes an efficient and versatile route for the elaboration of biobased thermoset from a wide range of phenolic compounds derived from renewable resources.

Breaking the symmetry of dibenzoxazines: a paradigm to tailor the design of bio-based thermosets

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C5GC03102H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

With the ongoing efforts to promote the development of bio-based dibenzoxazine thermosets, we explore herein a new strategy aiming at the synthesis of asymmetric dibenzoxazine monomers from naturally occurring phenolic compounds, cardanol and vanillin. By taking advantage of the low reactivity of cardanol, a monosubstituted cardanol-based benzoxazine monomer was prepared and further coupled with vanillin to yield vanillin–cardanol di-benzoxazines. The structural features of the resulting products were substantiated by ¹H NMR and HR-MS. The occurrence of the thermally-induced ring-opening polymerization was monitored by rheological measurements and DSC. At 190 °C the new asymmetric monomers showed a moderate gelation time (8 min) compared to 30–31 min revealed for cardanol-based (di-card) dibenzoxazines. Once polymerized, they exhibited a high T_g (129 °C), while the di-card flew under heating because of its low cross-linking density. Asymmetric monomers also exhibited lower melting temperatures than their symmetrical congeners based on vanillin, which significantly enlarge the processing window between the melting and polymerization temperatures up to 126 °C instead of 7 °C for symmetric vanillin-based dibenzoxazines. Therefore, such a strategy constitutes an efficient and versatile route for an easy elaboration of biobased monocomponent thermosets and can be applied to a wide range of phenolic compounds derived from renewable resources.

Breaking the symmetry of dibenzoxazines: a paradigm to tailor the design of bio-based thermosets

L. Puchot,^a^b P. Verge,*^a T. Fouquet,^c C. Vancaeyzeele,^b F. Vidal^b and Y. Habibi*^a

*Corresponding authors

^aLuxembourg Institute of Science and Technology (LIST), 5 avenue des Hauts-Fourneaux, L-4362 Esch-sur-Alzette, Luxembourg

E-mail: Pierre.verge@list.lu, Youssef.habibi@list.lu

^bLaboratoire de Physicochimie des Polymères et des Interfaces (LPPI – EA 2528), I-Mat, Université de Cergy-Pontoise, 5 mail Gay-Lussac, 95031 Cergy-Pontoise, France

^cEnvironmental Measurement Technology Group, Environmental Management and Research Institute (EMRI), National Institute of Advanced Industrial Science and Technology (AIST), Onogawa 16-1, Tsukuba, Japan

Green Chem., 2016, Advance Article

DOI: 10.1039/C5GC03102H

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ITI 214

phase 1 Comments Off

Mar 112016

ITI 214

IC200214; ITI-214

(6aR,9aS)-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-3-(phenylamino)-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4-(2H)-one phosphate

(6aR,9aS)-5-methyl-3-(phenylamino)-2-(4-(6-fluoropyridin-2-yl)-benzyl)-5,6a,7,8,9,9a-hexahydrocyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one…BASE

CAS: 1642303-38-5 (phosphate);

1160521-50-5 (free base).

Chemical Formula: C29H29FN7O5P
Molecular Weight: 605.5672

Takeda Pharmaceutical Company Limited,Intra-Cellular Therapies, Inc.

ITI-214 is an orally active, potent and Selective Inhibitors of Phosphodiesterase 1 for the Treatment of Cognitive Impairment Associated with Neurodegenerative and Neuropsychiatric Diseases. ITI-214 exhibited picomolar inhibitory potency for PDE1, demonstrated excellent selectivity against all other PDE families, and showed good efficacy in vivo. Currently, this investigational new drug is in Phase I clinical development and being considered for the treatment of several indications including cognitive deficits associated with schizophrenia and Alzheimer’s disease, movement disorders, attention deficit and hyperactivity disorders, and other CNS and non-CNS disorders.

Phase I Cognition disorders
- OriginatorIntra-Cellular Therapies
- ClassAntiparkinsonians; Nootropics; Small molecules
- Mechanism of ActionType 1 cyclic nucleotide phosphodiesterase inhibitors

21 Sep 2015Takeda completes a phase I bioavailability trial in Cognition disorders in Japan
21 Sep 2015Takeda completes a phase I trial in Cognition disorders in Japan
21 Sep 2015Takeda initiates enrolment in a phase I bioavailability trial for Cognition disorders in Japan before September 2015

Phosphodiesterase-1 (PDE-1) inhibitor

which is a picomolar PDE1 inhibitor with excellent selectivity against other PDE family members and against a panel of enzymes, receptors, transporters, and ion channels.

It is disclosed in WO 2009/075784 (U.S. Pub. No. 2010/0273754). This compound has been found to be a potent and selective phosphodiesterase 1 (PDE 1) inhibitor useful for the treatment or prophylaxis of disorders characterized by low levels of cAMP and/or cGMP in cells expressing PDE1, and/or reduced dopamine Dl receptor signaling activity (e.g., Parkinson’s disease, Tourette’s Syndrome, Autism, fragile X syndrome, ADHD, restless leg syndrome, depression, cognitive impairment of schizophrenia, narcolepsy); and/or any disease or condition that may be ameliorated by the enhancement of progesterone signaling. This list of disorders is exemplary and not intended to be exhaustive.

Intra-Cellular Therapies logo

PATENT

WO 2013192556

http://www.google.com/patents/WO2013192556A2?cl=en

The method of making the Compound (ea^^a^-S^a ^^^a-hexahydro-S- methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)- cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one is generally described in WO 2009/075784, the contents of which are incorporated by reference in their entirety. This compound can also be prepared as summarized or similarly summarized in the following

CMU PCU PHU PPU (SM2)

PATENT

http://www.google.com/patents/WO2009075784A1?cl=en

1 1. A compound according to claim 1 , wherein said compound is

EXAMPLE 14

(6aJ?,9aS)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6- fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]iinidazo[l,2-fl]pyrazolo[4,3- e]pyrimidin-4(2//)-one

This compound may be made using similar method as in example 13 wherein 2-(4-(bromomethyl)phenyl)-6-fluoropyridine may be used instead of 2-(4- (dibromomethyl)phenyl)-5-fluoropyridine.

PATENT

WO 2014205354

https://www.google.co.in/patents/WO2014205354A2?cl=en

EXAMPLES

The method of making the Compound (ea^^a^-S^a ^^^a-hexahydro-S-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one is generally described in WO 2009/075784, the contents of which are incorporated by reference in their entirety. This compound can also be prepared as summarized or similarly summarized in the following

CMU PCU PHU PPU (SM2)

In particular, (6aR,9aS)-3-chloro-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (Int-5) may be prepared as described or similarly described below. The free base crystals and the mono-phosphate salt crystals of the invention may be prepared by using the methods described or similarly described in Examples 1-14 below.

Preparation of (6aR,9aS)-3-chloro-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one

(4-(6-fluoropyridin-2-yl)phenyl)methanol

The mixture of Na₂C0₃ (121 g), water (500 mL), THF (650 mL), PdCl₂(PPh₃)₂ (997 mg), 2-bromo-6-fluoropyridine (100 g) and 4-(hydroxymethyl)phenylboronic acid (90.7 g) is stirred at 65°C for 4 h under the nitrogen atmosphere. After cooling to room temperature, THF (200 mL) is added. The organic layer is separated and washed with 5% NaCl solution twice. The organic layer is concentrated to 400 mL. After the addition of toluene (100 mL), heptane (500 mL) is added at 55°C. The mixture is cooled to room temperature. The crystals are isolated by filtration, washed with the mixture of toluene (100 mL) and heptane (100 mL) and dried to give (4-(6-fluoropyridin-2-yl)phenyl)methanol (103 g). ^]H NMR (500 MHz, CDC1₃) δ 1.71-1.78 (m, 1H), 4.74-4.79 (m, 2H), 6.84-6.88 (m, 1H), 7.44-7.50 (m, 2H), 7.61-7.65 (m, 1H), 7.80-7.88 (m, 1H), 7.98-8.04 (m, 2H).

2-(4-(chloromethyl)phenyl)-6-fluoropyridine

The solution of thionylchloride (43.1 mL) in AcOEt (200 mL) is added to the mixture of (4-(6-fluoropyridin-2-yl)phenyl)methanol (100 g), DMF (10 mL) and AcOEt (600 mL) at room temperature. The mixture is stirred at room temperature for 1 h. After cooling to 10°C, 15% Na₂C0₃ solution is added. The organic layer is separated and washed with water (500 mL) and 5% NaCl solution (500 mL) twice. The organic layer is concentrated to 500 mL. After the addition of EtOH (500 mL), the mixture is concentrated to 500 mL. After addition of EtOH (500 mL), the mixture is concentrated to 500 mL. After the addition of EtOH (500 mL), the mixture is concentrated to 500 mL. After addition of EtOH (200 mL), water (700 mL) is added at 40°C. The mixture is stirred at room temperature. The crystals are isolated by filtration and dried to give 2-(4-(chloromethyl)phenyl)-6-fluoropyridine (89.5 g). ^]H NMR (500 MHz, CDC1₃) δ 4.64 (s, 2H), 6.86-6.90 (m, 1H), 7.47-7.52 (m, 2H), 7.60-7.65 (m, 1H), 7.82-7.88 (m, 1H), 7.98-8.03 (m, 2H).

6-chloro-l-(4-methoxybenzyl)-3-methylpyrimidine-2,4(lH,3H)-dione

The mixture of 6-chloro-3-methyluracil (100 g), p-methoxybenzylchloride (107 g), K2CO₃ (86.1 g) and DMAc (600 mL) is stirred at 75°C for 4 h. Water (400 mL) is added at 45°C and the mixture is cooled to room temperature. Water (800 mL) is added and the mixture is stirred at room temperature. The crystals are isolated by filtration, washed with the mixture of DMAc and water (1:2, 200mL) and dried to give 6-chloro-l-(4-methoxybenzyl)-3-methylpyrimidine-2,4(lH,3H)-dione (167 g). ^]H NMR (500 MHz, CDC1₃) δ 3.35 (s, 3H), 3.80 (s, 3H), 5.21 (s, 2H), 5.93 (s, 1H), 6.85-6.89 (m, 2H), 7.26-7.32 (m, 2H).

izinyl-l-(4-methoxybenzyl)-3-methylpyrimidine-2,4(lH,3H)-dione

The mixture of 6-chloro-l-(4-methoxybenzyl)-3-methylpyrimidine-2,4(lH,3H)-dione (165 g), IPA (990 mL), water (124 mL) and hydrazine hydrate (62.9 mL) is stirred at room temperature for 1 h. The mixture is warmed to 60°C and stirred at the same temperature for 4 h. Isopropyl acetate (1485 mL) is added at 45°C and the mixture is stirred at the same temperature for 0.5 h. The mixture is cooled at 10°C and stirred for lh. The crystals are isolated by filtration, washed with the mixture of IPA and isopropyl acetate (1:2, 330 mL) and dried to give 6-hydrazinyl-l-(4-methoxybenzyl)-3-methylpyrimidine-2,4(lH,3H)-dione (153 g). ^]H NMR (500 MHz, DMSO-i¾) δ 3.12 (s, 3H), 3.71 (s, 3H), 4.36 (s, 2H), 5.01 (s, 2H), 5.14 (s, 1H), 6.87-6.89 (m, 2H), 7.12-7.17 (m, 2H), 8.04 (s, 1H).

7-(4-methoxybenzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione

To the mixture of DMF (725 mL) and 6-hydrazinyl-l-(4-methoxybenzyl)-3-methylpyrimidine-2,4(lH,3H)-dione (145 g) is added POCI₃ (58.5 mL) at 5°C. The mixture is stirred at room temperature for 1 h. Water (725 mL) is added at 50°C and the mixture is stirred at room temperature for 1 h. The crystals are isolated by filtration, washed with the mixture of DMF and water (1:1, 290 mL) and dried to give 7-(4-methoxybenzyl)-5-methyl-

2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (145 g). ^]H NMR (500 MHz, DMSO-i¾) δ 3.23 (s, 3H), 3.71 (s, 3H), 5.05 (s, 2H), 6.82-6.90 (m, 2H), 7.28-7.36 (m, 2H), 8.48 (s, IH), 13.51 (br, IH).

2-(4-(6-fluoropyridin-2-yl)benzyl)-7-(4-methoxybenzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione

The mixture of 2-(4-(chloromethyl)phenyl)-6-fluoropyridine (100 g), 7-(4-methoxybenzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (129 g), K2CO₃(62.3 g) and DMAc (1500 mL) is stirred at 45°C for 5 h. Water (1500 mL) is added at 40°C and the mixture is stirred at room temperature for 1 h. The crystals are isolated by filtration, washed with the mixture of DMAc and water (1:1, 500 mL) and dried to give 2-(4-(6-fluoropyridin-2-yl)benzyl)-7-(4-methoxybenzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (207 g). ^]H NMR (500 MHz, DMSO- ) δ 3.21 (s, 3H), 3.66 (s, 3H), 4.98 (s, 2H), 5.45 (s, 2H), 6.77-6.82 (m, 2H), 7.13-7.16 (m, IH), 7.25-7.30 (m, 2H), 7.41-7.44 (m, 2H), 7.92-7.96 (m, IH), 8.04-8.11 (m, 3H), 8.68 (s, IH).

2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione

The mixture of 2-(4-(6-fluoropyridin-2-yl)benzyl)-7-(4-methoxybenzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (105 g), CF₃COOH (300 mL) and

CF₃SO₃H (100 g) is stirred at room temperature for 10 h. Acetonitrile (1000 mL) is added. The mixture is added to the mixture of 25% N¾ (1000 mL) and acetonitrile (500 mL) at 10°C. The mixture is stirred at room temperature for 1 h. The crystals are isolated by filtration, washed with the mixture of acetonitirile and water (1:1, 500 mL) and dried to give the crude product. The mixture of the crude product and AcOEt (1200 mL) is stirred at room temperature for 1 h. The crystals are isolated by filtration, washed with AcOEt (250 mL) and dried to give 2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (75.3 g). ^]H NMR (500 MHz, DMSO-rf₆) δ 3.16 (s, 3H), 3.50-4.00 (br, 1H), 5.40 (s, 2H), 7.13-7.16 (m, 1H), 7.41-7.44 (m, 2H), 7.91-7.94 (m, 1H), 8.04-8.10 (m, 3H), 8.60 (s, 1H).

2-(4-(6-fluoropyridin-2-yl)benzyl)-6-(((lR,2R)-2-hydroxycyclopentyl)amino)-5-methyl-2H-pyrazolo[3,4-d]pyrimidin-4(5H)-one

The mixture of BOP reagent (126 g), 2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-2H-pyrazolo[3,4-d]pyrimidine-4,6(5H,7H)-dione (80 g), DBU (136 mL) and THF (1120 mL) is stirred at room temperature for 1 h. (lR,2R)-2-Aminocyclopentanol hydrochloride (37.6 g) and THF (80 mL) are added and the mixture is stirred at room temperature for 5 h. After the addition of 5% NaCl (400 mL) and AcOEt (800 mL), the organic layer is separated. The organic layer is washed with 10% NaCl (400 mL), 1M HC1 15% NaCl (400 mL), 5% NaCl (400 mL), 5% NaHC0₃ (400 mL) and 5%NaCl (400 mL) successively. After treatment with active charcoal, the organic layer is concentrated to 400 mL. After the addition of acetonitrile (800 mL), the mixture is concentrated to 400 mL. After the addition of acetonitrile (800 mL), seed crystals are added at 40°C. The mixture is concentrated to 400 mL. Water (800 mL) is added at room temperature and the mixture is stirred for 2 h. The crystals are isolated by filtration, washed with the mixture of acetonitrile and water (1:2, 400 mL) and dried to give 2-(4-(6-fluoropyridin-2-yl)benzyl)-6-(((lR,2R)-2-

hydroxycyclopentyl)amino)-5-methyl-2H-pyrazolo[3,4-d]pyrimidin-4(5H)-one (81.7 g). ^]H NMR (500 MHz, CDC1₃) δ 1.47-1.59 (m, 1H), 1.68-1.93 (m, 3H), 2.02-2.12 (m, 1H), 2.24-2.34 (m, 1H), 3.42 (s, 3H), 3.98-4.12 (m, 2H), 4.68-4.70 (m, 1H), 5.37 (s, 2H), 6.86-6.90 (m, 1H), 7.36-7.42 (m, 2H), 7.58-7.63 (m, 1H), 7.81-7.88 (m, 1H), 7.89 (s, 1H), 7.97-8.01 (m, 2H).

(6aR,9aS)-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one

The mixture of 2-(4-(6-fluoropyridin-2-yl)benzyl)-6-(((lR,2R)-2-hydroxycyclopentyl)amino)-5-methyl-2H-pyrazolo[3,4-d]pyrimidin-4(5H)-one (80 g), p-toluenesulfonylchloride (38.6 g), Et₃N (28.2 mL), N,N-dimethylaminopyridine (24.7 g) and THF (800 mL) is stirred at 50°C for 10 h. To the mixture is added 8M NaOH (11.5 mL) at room temperature and the mixture is stirred for 2 h. After the addition of 5% NaCl (400 mL) and AcOEt (800 mL), the organic layer is separated. The organic layer is washed with 5 NaCl (400 mL) twice. The organic layer is concentrated to 240 mL. After the addition of MeOH (800 mL), the mixture is concentrated to 240 mL. After the addition of MeOH (800 mL), the mixture is concentrated to 240 mL. After the addition of MeOH (160 mL), the mixture is stirred at room temperature for 1 h and at 0°C for 1 h. The crystals are isolated by filtration, washed with cold MeOH (160 mL) and dried to give (6aR,9aS)-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (55.7 g). ^]H NMR (500 MHz, CDC1₃) δ 1.39-1.54 (m, 1H), 1.58-1.81 (m, 3H), 1.81-1.92 (m, 1H), 2.12-2.22 (m, 1H), 3.28 (s, 3H), 4.61-4.70 (m, 2H), 5.20 (s, 2H), 6.79-6.85 (m, 1H), 7.25-7.32 (m, 2H), 7.53-7.58 (m, 1H), 7.68 (s, 1H), 7.75-7.83 (m, 1H), 7.92-7.98 (m, 2H).

(6aR,9aS)-3-chloro-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-

hexahydrocyclopenta[4,5]imi ]pyrimidin-4(2H)-one

The mixture of (6aR,9aS)-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (50 g) and toluene (1000 mL) is concentrated to 750 mL under the nitrogen atmosphere. Toluene (250 mL) and NCS (24 g) is added. To the mixture is added LiHMDS (1M THF solution, 204 mL) at 0°C and the mixture is stirred for 0.5 h. To the mixture is added 20% NH₄C1 (50 mL) at 5°C. The mixture is concentrated to 250 mL. After the addition of EtOH (250 mL), the mixture is concentrated to 150 mL. After the addition of EtOH (250 mL), the mixture is concentrated to 200 mL. After the addition of EtOH (200 mL), the mixture is warmed to 50°C. Water (300 mL) is added and the mixture is stirred at 50°C for 0.5 h. After stirring at room temperature for 1 h, the crystals are isolated by filtration, washed with the mixture of EtOH and water (1:1, 150 mL) and dried to give (6aR,9aS)-3-chloro-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one (51.1 g). ^]H NMR (500 MHz, CDC1₃) δ 1.46-1.61 (m, 1H), 1.67-1.90 (m, 3H), 1.92-2.00 (m, 1H), 2.19-2.27 (m, 1H), 3.37 (s, 3H), 4.66-4.77 (m, 2H), 5.34 (s, 2H), 6.87-6.93 (m, 1H), 7.35-7.41 (m, 2H), 7.59-7.65 (m, 1H), 7.82-7.91 (m, 1H), 7.97-8.05 (m, 2H).

EXAMPLE 1

Crystals of (6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base mono-ethanol solvate

The mixture of (6a/?,9a5′)-3-chloro-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one (2.5 g), K₂C0₃ (1.53 g), Pd(OAc)₂ (12.5 mg), Xantphos (32 mg), aniline (0.76 mL), and xylene (12.5 mL) is stirred at 125°C for 7 h under nitrogen atmosphere. After addition of water (12.5 mL), the organic layer is separated. The organic layer is washed with water (12.5 mL) twice. The organic layer is extracted with the mixture of DMAc (6.25 mL) and 0.5N HCl (12.5 mL). The organic layer is extracted with the mixture of DMAc (3.2 mL) and 0.5N HCl (6.25 mL). After addition of DMAc (6.25 mL), xylene (12.5 mL) and 25 wt % aqueous NH₃ solution to the combined aqueous layer, the organic layer is separated. The aqueous layer is extracted with xylene (6.25 mL). The combined organic layer is washed with water (12.5 mL), 2.5 wt % aqueous 1 ,2-cyclohexanediamine solution (12.5 mL) twice and water (12.5 mL) successively. After treatment with active charcoal, the organic layer is concentrated. After addition of EtOH (12.5 mL), the mixture is concentrated. After addition of EtOH (12.5 mL), the mixture is concentrated. After addition of EtOH (12.5 mL), n-heptane (25 mL) is added at 70°C. The mixture is cooled to 5°C and stirred at same temperature. The crystals are isolated by filtration and dried to give (ea^^a^-S^a ^^^a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base mono-ethanol solvate (2.56 g) as crystals.

^]H NMR (500 MHz, DMSO-d₆) δ 0.98-1.13 (m, 3H), 1.34-1.52 (m, 1H), 1.54-1.83 (m, 4H), 2.03-2.17 (m, 1H), 3.11 (s, 3H), 3.39-3.54 (m, 2H), 4.29-4.43 (m, 1H), 4.51-4.60 (m, 1H), 4.60-4.70 (m, 1H), 5.15-5.35 (m, 2H), 6.71-6.88 (m, 3H), 7.05-7.29 (m, 5H), 7.81-7.93 (m, 1H), 7.94-8.11 (m, 3H), 8.67 (s, 1H).

EXAMPLE 4

Crystals of (6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one free

Crystals of (6a«,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base mono-n-propanol solvate (2.0 g) is dissolved with ethanol (10 mL) at 70°C. Isopropyl ether (20 mL) is added and the mixture is cooled to 45°C. Isopropyl ether (10 mL) is added and the mixture is stirred at 40°C. The mixture is cooled to 5°C and stirred at same temperature. The crystals are isolated by filtration and dried to give (ea/^^a^)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base non-solvate (1.7 g) as crystals.

[0082] ^]H NMR (500 MHz, DMSO-d₆) δ 1.32-1.51 (m, 1H), 1.53-1.83 (m, 4H), 1.97-2.20 (m, 1H), 3.11 (s, 3H), 4.49-4.60 (m, 1H), 4.60-4.69 (m, 1H), 5.13-5.37 (m, 2H), 6.70-6.90 (m, 3H), 7.04-7.31 (m, 5H), 7.82-7.93 (m, 1H), 7.93-8.12 (m, 3H), 8.67 (s, 1H).

EXAMPLE 5

Crystals of (6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base non-solvate

The mixture of (6a/?,9a5′)-3-chloro-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one (25 g), K₂C0₃ (15.4 g), Pd(OAc)₂ (125 mg), Xantphos (321 mg), aniline (7.6 mL), DMAc (6.25 mL) and xylene (125 mL) is stirred at 125°C for 6.5 h under nitrogen atmosphere. After addition of water (125 mL) and DMAc (50 mL), the organic layer is separated. The organic layer is washed with the mixture of DMAc (50 mL) and water (125 mL) twice. The organic layer is extracted with the mixture of DMAc (50 mL) and 0.5N HCl (125 mL). The organic layer is extracted with the mixture of DMAc (50 mL) and 0.5N HCl (62.5 mL). After addition of DMAc (50 mL), xylene (125 mL) and 25 wt % aqueous NH₃ solution (25 mL) to the combined aqueous layer, the organic layer is separated. The aqueous layer is extracted with xylene (62.5 mL). The combined organic layer is washed with the mixture of DMAc (50 mL) and water (125 mL), the mixture of DMAc (50 mL) and 2.5 wt % aqueous 1,2-cyclohexanediamine solution (125 mL) twice and the mixture of DMAc (50 mL) and water (125 mL) successively. After treatment with active charcoal (1.25 g), the organic layer is concentrated to 75 mL. After addition of EtOH (125 mL), the mixture is concentrated to 75 mL. After addition of EtOH (125 mL), the mixture is concentrated to 75 mL. After addition of EtOH (125 mL), n-heptane (250 mL) is added at 70°C. After addition of seed crystals of (6a/?,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one non-solvate, the mixture is cooled to room temperature and stirred at room temperature. The crystals are isolated by filtration and dried to give (ea^^a^-S^a ^^^a-hexahydro-S-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo-[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base non-solvate (23.8 g) as crystals.

EXAMPLE 8

(6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt

[0094] Crystals of (6a«,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base non-solvate (20 g) are dissolved in acetonitrile (60 mL) at 50°C. After addition of the active charcoal (1 g), the mixture is stirred at same temperature for 0.5 h. The active charcoal is removed by filtration and washed with acetonitrile (40 mL). The filtrate and the washing are combined and warmed to 50°C. A solution of 85 wt. % phosphoric acid (2.64 mL) in acetonitrile (100 mL) is added. After addition of water (20 mL), the mixture is stirred at 50°C for lh. The crystals are isolated by filtration, washed with acetonitrile (60 mL x 3) and dried to give (6a/?,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt (20.5 g).

EXAMPLE 9

(6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt

[0095] Crystals of (6a«,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base mono-ethanol solvate (4 g) are dissolved in acetonitrile (12 mL) at 50°C. After addition of active charcoal (0.2 g), the mixture is stirred at same temperature for 0.5 h. Active charcoal is removed by filtration and washed with acetonitrile (8 mL). The filtrate and the washing are combined and warmed to 50°C. A solution of 85 wt. % phosphoric acid (0.528 mL) in acetonitrile (20 mL) is added. After addition of water (4 mL), the mixture is stirred at 50°C for lh. The crystals are isolated by filtration, washed with acetonitrile (12 mL x 3) and dried to give (6a/?,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt (4.01 g).

EXAMPLE 10

(6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt

Crystals of (6a«,9a5′)-5,6a,7,8,9,9a-Hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base non-solvate (20 g) are dissolved in acetone (60 mL) at 32°C. After addition of active charcoal (1 g), the mixture is stirred at same temperature for 0.5 h. Active charcoal is removed by filtration and washed with acetone (40 mL). The filtrate and the washing are combined and warmed to 39°C. A solution of 85 wt. % phosphoric acid (2.64 mL) in acetone (100 mL) is added. After addition of water (20 mL), the mixture is stirred at 40°C for lh. The crystals are isolated by filtration, washed with acetone (60 mL x 3) and dried to give (6a/?,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt (22.86 g).

EXAMPLE 11

(6a/f,9a5)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt

Crystals of (6a«,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one free base mono-ethanol solvate (20 g) are dissolved in acetone (60 mL) at 38°C. After addition of active charcoal (1 g), the mixture is stirred at same temperature for 0.5 h. Active charcoal is removed by filtration and washed with acetone (40 mL). The filtrate and the washing are combined and warmed to 38°C. A solution of 85 wt. % phosphoric acid (2.64 mL) in acetone (100 mL) is added. After addition of water (20 mL), the mixture is stirred at 40°C for lh. The crystals are isolated by filtration, washed with acetone (60 mL x 3) and dried to give (6a/?,9a5′)-5,6a,7,8,9,9a-hexahydro-5-methyl-3-(phenylamino)-2-((4-(6-fluoropyridin-2-yl)phenyl)methyl)-cyclopent[4,5]imidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one mono-phosphate salt (23.2 g).

PAPER

A diverse set of 3-aminopyrazolo[3,4-d]pyrimidinones was designed and synthesized. The structure–activity relationships of these polycyclic compounds as phosphodiesterase 1 (PDE1) inhibitors were studied along with their physicochemical and pharmacokinetic properties. Systematic optimizations of this novel scaffold culminated in the identification of a clinical candidate, (6aR,9aS)-2-(4-(6-fluoropyridin-2-yl)benzyl)-5-methyl-3-(phenylamino)-5,6a,7,8,9,9a-hexahydrocyclopenta[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4-(2H)-one phosphate (ITI-214), which exhibited picomolar inhibitory potency for PDE1, demonstrated excellent selectivity against all other PDE families and showed good efficacy in vivo. Currently, this investigational new drug is in Phase I clinical development and being considered for the treatment of several indications including cognitive deficits associated with schizophrenia and Alzheimer’s disease, movement disorders, attention deficit and hyperactivity disorders, and other central nervous system (CNS) and non-CNS disorders

Discovery of Potent and Selective Inhibitors of Phosphodiesterase 1 for the Treatment of Cognitive Impairment Associated with Neurodegenerative and Neuropsychiatric Diseases

Peng Li^*^†, Hailin Zheng^†, Jun Zhao^†, Lei Zhang^†, Wei Yao^†, Hongwen Zhu^†, J. David Beard^†, Koh Ida^§, Weston Lane^‡, Gyorgy Snell^‡, Satoshi Sogabe^§, Charles J. Heyser^∥, Gretchen L. Snyder^†, Joseph P. Hendrick^†, Kimberly E. Vanover^†, Robert E. Davis^†, and Lawrence P. Wennogle^†

^†Intra-Cellular Therapies, Inc., 430 East 29th Street, Suite 900, New York, New York 10016, United States

^‡ Department of Structural Biology, Takeda California, Inc., 10410 Science Center Drive, San Diego, California 92121,United States

^§ Pharmaceutical Research Division, Takeda Pharmaceutical Company, Ltd., 26-1, Muraoka-Higashi 2-Chome, Fujisawa, Kanagawa 251-8555, Japan

^∥ Department of Neurosciences, University of California, San Diego, 9500 Gilman Drive, #0608, La Jolla, California 92093,United States

J. Med. Chem., 2016, 59 (3), pp 1149–1164

DOI: 10.1021/acs.jmedchem.5b01751

Publication Date (Web): January 20, 2016

*Phone: 646-440-9388. E-mail: pli@intracellulartherapies.com.

http://pubs.acs.org/doi/full/10.1021/acs.jmedchem.5b01751

Step g. (6aR,9aS)-5-Methyl-3-(phenylamino)-2-(4-(6-fluoropyridin-2-yl)-benzyl)-5,6a,7,8,9,9a-hexahydrocyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one phosphate (3)

………… to give (6aR,9aS)-5-methyl-3-(phenylamino)-2-(4-(6-fluoropyridin-2-yl)-benzyl)-5,6a,7,8,9,9a-hexahydrocyclopent[4,5]imidazo[1,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one as an off-white solid

BASE FORM

¹H NMR (500 MHz, CDCl₃) δ 7.89 (d, J = 8.3 Hz, 2H), 7.86–7.79 (m, 1H), 7.58 (dd, J = 7.6, 2.5 Hz, 1H), 7.35–7.26 (m, 2H), 7.15–7.08 (m, 1H), 7.05 (d, J = 8.3 Hz, 2H), 6.94 (d, J = 7.6 Hz, 2H), 6.90 (br, 1H), 6.86 (dd, J = 8.1, 3.0 Hz, 1H), 4.96 (s, 2H), 4.88–4.70 (m, 2H), 3.38 (s, 3H), 2.29 (dd, J = 13.0, 6.1 Hz, 1H), 2.15–1.96 (m, 1H), 1.90–1.71 (m, 3H), 1.65–1.52 (m, 1H).

¹³C NMR (126 MHz, CDCl₃) δ 163.4 (d, J_CF = 239 Hz), 159.7, 155.7 (d, J_CF = 13 Hz), 153.0, 147.6, 144.1, 141.7 (d, J_CF = 8 Hz), 140.5, 137.3, 137.1, 129.6, 127.8, 127.1, 124.1, 120.2, 117.3 (d, J_CF = 4 Hz), 107.9 (d, J_CF = 38 Hz), 89.5, 69.9, 62.6, 52.8, 35.4, 32.3, 28.5, 23.2.

MS (ESI) m/z 508.3 [M + H]⁺.

PHOSPHATE SALT

¹H NMR (500 MHz, DMSO-d₆) δ 8.71 (br, 1H), 8.10–8.01 (m, 1H), 7.98 (d, J = 8.3 Hz, 2H), 7.89 (dd, J = 7.6, 2.6 Hz, 1H), 7.23 (d, J = 8.4 Hz, 2H), 7.16 (dd, J = 8.5, 7.3 Hz, 2H), 7.12 (dd, J = 8.1, 2.8 Hz, 1H), 6.86–6.81 (m, 1H), 6.80–6.76 (m, 2H), 5.34–5.19 (m, 2H), 4.77–4.64 (m, 1H), 4.62–4.53 (m, 1H), 3.12 (s, 3H), 2.11 (dd, J = 13.4, 5.7 Hz, 1H), 1.81–1.57 (m, 4H), 1.54–1.41 (m, 1H).

¹³C NMR (126 MHz, CDCl₃) δ 162.6 (d, J_CF = 236 Hz), 155.9, 154.4 (d, J_CF= 13 Hz), 152.4, 146.6, 143.0 (d, J_CF = 8 Hz), 142.5, 141.8, 138.1, 136.0, 128.7, 127.5, 126.7, 120.4, 117.7 (d, J_CF = 4 Hz), 116.0, 108.1 (d, J_CF = 37 Hz), 90.3, 66.3, 62.4, 50.6, 34.2, 31.2, 28.5, 22.5.

MS (ESI) m/z 508.3 [M + H]⁺.

HRMS (ESI) m/z calcd for C₂₉H₂₇N₇OF [M (free base)+H]⁺, 508.2261; found, 508.2272.

HPLC purity, 100.0%; retention time, 13.0 min.

PATENT

WO2015196186

The synthetic methods disclosed in WO 2009/075784 and WO 2013/192556 are particularly applicable, as they include the methods to prepare the compound of Formula I-B. Those skilled in the art will readily see how those methods are applicable to the synthesis of the compounds of the present invention.

Formula I-B

For example, Compounds of the Invention wherein any one or more of R¹ through R⁸ are D, can be prepared from the corresponding aminocyclopentanol, according to the method described in WO 2009/075784 or WO 2013/192556. For example, by reacting said aminocyclopentanol, optionally as its acid salt, with Intermediate A in the presence of a coupling agent, e.g., benzotriazol-1-yloxy)tris(dimethylamino)phosphonium hexafluorophosphate (BOP reagent), and a base, e.g., l,8-diazabicyclo[5.4.0]undec-7-ene (DBU), in a solvent such as tetrahydrofuran (THF). The intermediate alcohol is then cyclized by treatment with toluenesulfonyl chloride (TsCl) in the presence of one or more bases, such as dimethylaminopyridine (DMAP) and triethylamine (TEA) in a solvent, such as THF. The reaction is summarized in the following scheme:

The required aminocyclopentanols can be prepared by methods known to those skilled in the art. For example, the aminocyclopentanol wherein R¹ is D can be prepared via a reductive amination procedure that uses a reducing agent such as sodium triacetoxyborodeuteride or sodium borodeuteride as the reducing agent. For example, an optionally protected (R)-2-hydroxycyclopentanone can be reacted with 4-methoxybenzylamine in the presence of sodium triacetoxyborodeuteride to yield the desired deuterated secondary amine, wherein P is the protecting group. Reaction of the resulting amine with a strong acid such as trifluoromethanesulfonic acid (TMFSA) will result in removal of the 4-methoxybenzyl group and the protecting group to yield the desired aminocyclopentanol. Those skilled in the art will know how to choose a suitable protecting group for the secondary alcohol such that deprotection can take place during the acid treatment step (e.g., a tert-butyldimethylsilyl group or a tert-butoxycarbonyl group). Alternatively, those skilled in the art could choose a protecting group that would survive this step. If desired, the protected intermediate can be purified by chiral HPLC in order to enhance the optical purity of the final

As another example, Compounds of the Invention wherein any one or more of R⁹ to R¹⁵ or R²¹ to R²² are D can be prepared from the corresponding benzyl halide, according to the method described in WO 2009/075784 or WO 2013/192556. For example, by reacting said benzyl halide with the Intermediate B in the presence of suitable base, such as cesium carbonate or potassium carbonate, in a suitable solvent, such as dimethylformamide or dimethylacetamide. The corresponding benzyl halide can be prepared by methods well known to those skilled in the art. The reaction is summarized in the following scheme:

As another example, compounds of the invention wherein any one or more of R¹⁶ to R²⁰ are D can be prepared from the corresponding phenyl

isothiocyanate, according to the method described in WO 2009/075784 or WO

2013/192556. For example, by reacting said phenyl isothiocyanate with Intermediate C in a suitable solvent, such as dimethylformamide. The corresponding phenyl isothiocyanate can be prepared by methods well known to those skilled in the art. The reaction is summarized in the following scheme:

Alternatively, compounds of the invention wherein any one or more of R¹⁶ to R²⁰ are D can be prepared from the corresponding aniline, according to the method described in WO 2009/075784 or WO 2013/192556. For example, by reacting said aniline with Intermediate D and a strong base, such as lithium

hexamethyldisilylazide (LiHMDS), in a suitable solvent, such as THF at elevated temperature. Such a reaction can also be achieved by catalytic amination using a catalyst, such as tris(dibenzylideneacetone)dipalladium (Pd₂(dba)3), and a ligand, such as Xantphos. The corresponding aniline can be prepared by methods well known to those skil

EXAMPLE 1. (6aR,9a5)-5-Methyl-3-(2,3,4,5,6-pentadeuterophenylamino)-2-(4-(6-fluoropyridin-2-yl)-benzyl)-5,6fl,7,8,9,9fl-hexahydrocyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one

To a solution of (6a/?,9a5′)-5,6a,7,8,9,9a-hexahydro-3-chloro-5-methyl-2-(4-(6-fluoropyridin-2-yl)-benzyl)-cyclopent[4,5]irnidazo[l,2-fl]pyrazolo[4,3-e]pyrimidin-4(2H)-one (200 mg, 0.444 mmol) and 2,3,4,5,6-pentadeuteroaniline (162 μΐ,, 1.8 mmol) in anhydrous 2-methyltetrahydrofuran (3 mL) is added LiHMDS (1.0 M in THF, 0.89 mL) dropwise at room temperature under argon atmosphere. The reaction mixture is gradually heated to 75 °C over a period of 90 min, and then heated at 75 °C for an hour. The mixture is cooled with an ice bath and then quenched by adding 0.2 mL of water. After solvent evaporation, the residue is dissolved in DMF and then filter with a 0.45 m microfilter. The collected filtrated is purified with a semi-preparative HPLC system using a gradient of 0 – 70% acetonitrile in water containing 0.1% formic acid over 16 min to give (6a/?,9a5′)-5-methyl-3-(2,3,4,5,6-pentadeuterophenylamino)-2-(4-(6-fluoropyridin-2-yl)-benzyl)-5,6fl,7,8,9,9fl-hexahydrocyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one as a formate salt, which is dissolved in ethyl acetate, basified with 12.5 mL of 5% sodium carbonate, and then extracted with ethyl acetate three times. The combined organic phase is evaporated to dryness. The residue is dissolved in 4.5 mL of THF and then filter through a 0.45 m microfilter. The filtrate is evaporated to dryness and further dried under vacuum to give (6a/?,9a5′)-5-methyl-3-(2,3,4,5,6-pentadeuterophenylamino)-2-(4-(6-fluoropyridin-2-yl)-benzyl)-5,6fl,7,8,9,9fl-hexahydrocyclopent[4,5]imidazo[l,2-a]pyrazolo[4,3-e]pyrimidin-4(2H)-one as a white solid (185.8 mg, 81.6% yield). ¾ NMR (400 MHz, CDCb) δ 7.88 (d, / = 8.4 Hz, 2H), 7.88 – 7.77 (m, 1H), 7.58 (dd, J = 7.5, 2.4 Hz, 1H), 7.05 (d, J = 8.3 Hz, 2H), 6.90 – 6.80 (m, 2H), 4.94 (s, 2H), 4.82 – 4.68 (m, 2H), 3.34 (s, 3H), 2.27 (dd, / = 12.4, 5.7 Hz, 1H), 2.09 – 1.91 (m, 1H), 1.91 – 1.67 (m, 3H), 1.67 – 1.49 (m, 1H).MS (ESI) m/z 513.3 [M+H]⁺.

Nov 3, 2014

Intra-Cellular Therapies and Takeda Announce Mutual Termination of Collaboration to Develop Phosphodiesterase (PDE1) Inhibitors for CNS Disorders

NEW YORK and OSAKA, Japan, Nov. 3, 2014 (GLOBE NEWSWIRE) — Intra-Cellular Therapies, Inc. (Nasdaq:ITCI) and Takeda Pharmaceutical Company Limited announced today that they have entered into an agreement to mutually terminate the February 2011 license agreement covering Intra-Cellular Therapies’ proprietary compound ITI-214 and related PDE1 inhibitors and to return the rights for these compounds to Intra-Cellular Therapies.

Under the terms of the agreement, Intra-Cellular Therapies has regained all worldwide development and commercialization rights for the compounds previously licensed to Takeda. Takeda will be responsible for transitioning the compounds back toIntra-Cellular Therapies and will not participate in future development or commercialization activities. After transition of the program, Intra-Cellular Therapies plans to continue the clinical development of PDE1 inhibitors for the treatment of central nervous system, cardiovascular and other disorders.

“We are grateful for Takeda’s substantial efforts in advancing this program into clinical development,” said Dr. Sharon Mates, Chairman and CEO of Intra-Cellular Therapies. “This provides us with the opportunity to unify our PDE1 platform and we look forward to continuing the development of ITI-214 and our other PDE1 inhibitors.”

Intra-Cellular Therapies will discuss the PDE1 program in its previously announced earnings call on Monday, November 3, 2014 at 8:30 a.m. Eastern Time. To participate in the conference call, please dial 844-835-6563 (U.S.) or 970-315-3916 (International) five to ten minutes prior to the start of the call. The participant passcode is 25568442.

About PDE1 Inhibitors

PDE1 inhibitors are unique, orally available, investigational drug candidates being developed for the treatment of cognitive impairments accompanying schizophrenia, Alzheimer’s disease and other neuropsychiatric disorders and neurological diseases and may also treat patients with Attention Deficit Hyperactivity Disorder and Parkinson’s disease. These compounds may also have the potential to improve motor dysfunction associated with these conditions and may also have the potential to treat patients with multiple sclerosis and other autoimmune diseases and pulmonary arterial hypertension. These compounds are very selective for the PDE1 subfamily relative to other PDE subfamilies. They have no known significant off target activities at other enzymes, receptors or ion channels.

About Intra-Cellular Therapies

Intra-Cellular Therapies, Inc. (the “Company”) is developing novel drugs for the treatment of neuropsychiatric and neurodegenerative disease and other disorders of the central nervous system (“CNS”). The Company is developing its lead drug candidate, ITI-007, for the treatment of schizophrenia, behavioral disturbances in dementia, bipolar disorder and other neuropsychiatric and neurological disorders. The Company is also utilizing its phosphodiesterase platform and other proprietary chemistry platforms to develop drugs for the treatment of CNS disorders.

About Takeda Pharmaceutical Company Limited

Located in Osaka, Japan, Takeda is a research-based global company with its main focus on pharmaceuticals. As the largest pharmaceutical company in Japan and one of the global leaders of the industry, Takeda is committed to strive towards better health for people worldwide through leading innovation in medicine. Additional information about Takeda is available through its corporate website, www.Takeda.com.

Source: Intra-Cellular Therapies, Inc.; Takeda Pharmaceutical Company Limited

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WO2013192556A2 *	Jun 21, 2013	Dec 27, 2013	Intra-Cellular Therapies, Inc.	Salt crystal

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O=C(C1=C(NC2=CC=CC=C2)N(CC3=CC=C(C4=NC(F)=CC=C4)C=C3)N=C1N56)N(C)C5=N[C@@]7([H])[C@]6([H])CCC7.O=P(O)(O)O

Fc1cccc(n1)c2ccc(cc2)Cn7nc5N3C(=N[C@@H]4CCC[C@H]34)N(C)C(=O)c5c7Nc6ccccc6

Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

PROCESS, SYNTHESIS Comments Off

Mar 102016

Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

Green Chem., 2016, Advance Article
DOI: 10.1039/C5GC02920A, Communication

Anuja Nagendiran, Henrik Sorensen, Magnus J. Johansson, Cheuk-Wai Tai, Jan-E. Backvall
A continuous-flow approach towards the selective nanopalladium-catalyzed hydrogenation of the olefinic bond in various Michael acceptors, which could lead to a greener and more sustainable process, has been developed.

A continuous-flow approach towards the selective nanopalladium-catalyzed hydrogenation of the olefinic bond in various Michael acceptors, which could lead to a greener and more sustainable process, has been developed. The nanopalladium is supported on aminofunctionalized mesocellular foam. Both aromatic and aliphatic substrates, covering a variation of functional groups such as acids, aldehydes, esters, ketones, and nitriles were selectively hydrogenated in high to excellent yields using two different flow-devices (H-Cube® and Vapourtec). The catalyst was able to hydrogenate cinnamaldehyde continuously for 24 h (in total hydrogenating 19 g cinnanmaldehyde using 70 mg of catalyst in the H-cube®) without showing any significant decrease in activity or selectivity. Furthermore, the metal leaching of the catalyst was found to be very low (ppb amounts) in the two flow devices

3 Gottlieb, H. E.; Kotlyar, V; Nudelman, A. J. Org. Chem. 1997, 62, 7512-7515.

Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

Anuja Nagendiran,^a^b Henrik Sörensen,^b^c Magnus J. Johansson,^b^c Cheuk-Wai Tai^d and Jan-E. Bäckvall*^a^b

*Corresponding authors

^aDepartment of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
E-mail: jeb@organ.su.se

^bBerzelii Centre EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden

^cAstraZeneca R&D, Innovative Medicines, Cardiovascular and Metabolic Disorders, Medicinal Chemistry, Pepparedsleden 1, SE-431 83 Mölndal, Sweden

^dDepartment of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91, Stockholm, Sweden

Green Chem., 2016, Advance Article

DOI: 10.1039/C5GC02920A

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C5GC02920A?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

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Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

PROCESS, SYNTHESIS Comments Off

Mar 102016

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Green Chem., 2016, Advance Article
DOI: 10.1039/C6GC00384B, Paper

Daolai Sun, Eisyun Kitamura, Yasuhiro Yamada, Satoshi Sato
Nitriles were efficiently produced in a vapor-phase dehydration of aldoximes over SiO₂ catalysts without external heat supply.

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00384B?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

A vapor-phase dehydration of acetaldoxime to acetonitrile was investigated over various solid catalysts. Among the tested catalysts, ZrO₂, Al₂O₃ and SiO₂ showed high catalytic activity for the formation of acetonitrile from acetaldoxime, while the correlation between catalytic activity and the acid property of the catalysts was not observed. Weak acidic sites such as silanols sufficiently work as catalytic sites for the dehydration, which does not require strong acids such as zeolites. Several SiO₂ catalysts with different physical properties were tested, and the SiO₂with the smallest pore size and the highest specific surface area showed the highest catalytic activity for the formation of acetonitrile. Because the dehydration of acetaldoxime to acetonitrile is exothermic, a large amount of reaction heat was generated during the reaction, and the reaction temperature was found to be significantly affected by the feed rate of the reactant and the flow rate of the carrier gas. In order to effectively utilize the in situ generated reaction heat, the dehydration of acetaldoxime to acetonitrile without using the external heat supply was conducted. The temperature was controllable even in the absence of the external heat, and the acetonitrile yield higher than 90% could be achieved in such a green operation under the environment-friendly adiabatic conditions.

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Daolai Sun,^a Eisyun Kitamura,^a Yasuhiro Yamada^a and Satoshi Sato*^a

*Corresponding authors

^aGraduate School of Engineering, Chiba University, Chiba, Japan
E-mail: satoshi@faculty.chiba-u.jp
Fax: +81 43 290 3401
Tel: +81 43 290 3377

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00384B

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Crystallization of Artemisinin from Chromatography Fractions of Artemisia annua Extract

PROCESS Comments Off

Mar 102016

Crystallization is an inevitable step in the purification of artemisinin either from the plantArtemisia annua or from reaction mixtures of semisynthetically produced artemisinin.

Rational design of crystallization process requires knowledge about the solid–liquid equilibrium in a given solvent system and effect of impurities on it.

In the present work, a crystallization process was designed to purify artemisinin from fractions of a flash chromatography column effluent collected after injecting extracts of Artemisia annua leaves.

The fractions from chromatography containing artemisinin were combined together into one fraction, and the impurities present in this fraction were identified.

The solubility of artemisinin in the mobile phase used for chromatography, i.e.,n-hexane–ethyl acetate mixture of varying compositions, was measured at 25, 15, and 5 °C, respectively. The collective effect of impurities present in the combined fraction on the solid–liquid equilibrium of artemisinin was evaluated by measuring the solubility of artemisinin in the combined fraction at same temperatures. The results show that the impurities present in the combined fraction increase the solubility of artemisinin.

Finally, the crystallization of artemisinin from the combined fraction designed on the basis of artemisinin solubility data was carried out in two steps by adding an antisolvent and cooling crystallization.

The yield of artemisinin obtained in the process was 50%, and it was found that the impurities present in the combined fraction at a given concentration do not affect the crystallization of artemisinin.

Figure 2. Chemical structure of artemisinin (1) and impurities [artemisitene (2), dihydroartemisinic acid (3), artemisinic acid (4), arteannuin B (5), and coumarin (6)] found in the combined fraction.

Crystallization of Artemisinin from Chromatography Fractions ofArtemisia annua Extract

Chandrakant Ramkrishna Malwade^*^†, Hannes Buchholz^‡, Ben-Guang Rong^†, Haiyan Qu^†, Lars Porskjær Christensen^†, H. Lorenz^‡, and A. Seidel-Morgenstern^‡^§

^† Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark

^‡Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany

^§ Institute of Process Engineering, Otto von Guericke University, 39106 Magdeburg, Germany

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.5b00399

Publication Date (Web): February 09, 2016

*E-mail: crm@kbm.sdu.dk; phone: 0045 65508669.

http://pubs.acs.org/doi/abs/10.1021/acs.oprd.5b00399

Chandrakant Malwade

PhD

PostDoc

University of Southern Denmark,

Odense · Department of Chemical Engineering, Biotechnology and Environmental Technology

https://www.researchgate.net/profile/Chandrakant_Malwade/info

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Pd(II) pincer type complex catalyzed tandem C-H and N-H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

spectroscopy, SYNTHESIS Comments Off

Mar 072016

Pd(II) pincer type complex catalyzed tandem C-H and N-H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

Green Chem., 2016, Advance Article
DOI: 10.1039/C5GC02937F, Paper

Vignesh Arumugam, Werner Kaminsky, Dharmaraj Nallasamy
NNO Pincer type Pd(II) complex catalyzed one-pot synthesis of N-acetylcarbazoles in aqueous media is presented.

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C5GC02937F?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

One-pot, tandem C–H and N–H activation of acetanilides with aryl boronic acids to realize functionalized carbazoles was conveniently performed under aerobic conditions using a novelNNO pincer type Pd(II) complex [Pd(L)Cl] (where L = nicotinic acid (phenyl-pyridin-2-yl-methylene)-hydrazide or furan-2-carboxylic acid (phenyl-pyridin-2-yl-methylene)-hydrazide) as a catalyst in neat water and a very low (0.01 mol%) amount of catalyst. It is worth noting that recyclability up to six consecutive runs and column chromatography free isolation of the title heterocycles in an excellent yield are achieved.

Pd(II) pincer type complex catalyzed tandem C–H and N–H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

Vignesh Arumugam,^a Werner Kaminsky^b and Dharmaraj Nallasamy*^a

*Corresponding authors

^aInorganic & Nanomaterials Research Laboratory, Department of Chemistry, Bharathiar University, Coimbatore 641 046, India
E-mail: dharmaraj@buc.edu.in
Web: http://ndharmaraj.wix.com/inrl
Fax: +91 4222422387
Tel: +91 4222428316

^bDepartment of Chemistry, University of Washington, Seattle, USA

Green Chem., 2016, Advance Article

DOI: 10.1039/C5GC02937F

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Catalyst-free thiolation of indoles with sulfonyl hydrazides for the synthesis of 3-sulfenylindoles in water

spectroscopy Comments Off

Mar 072016

Catalyst-free thiolation of indoles with sulfonyl hydrazides for the synthesis of 3-sulfenylindoles in water

Green Chem., 2016, Advance Article
DOI: 10.1039/C6GC00313C, Communication

Yu Yang, Sheng Zhang, Lin Tang, Yanbin Hu, Zhenggen Zha, Zhiyong Wang
A water promoted thiolation of indoles with sulfonyl hydrazides has been developed under mild conditions in water.

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00313C?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

A catalyst-free thiolation of indoles with sulfonyl hydrazides was efficiently developed in water under mild conditions without any ligand or additive. The reaction provided a variety of 3-sulfenylindoles with good to excellent yields and the only by-products were nitrogen and water.

[1] F.-L. Yang, X.-T. Ma and S.-K. Tian, Chem. Eur. J., 2012, 18, 1582

Catalyst-free thiolation of indoles with sulfonyl hydrazides for the synthesis of 3-sulfenylindoles in water

Yu Yang,^a Sheng Zhang,^a Lin Tang,^a Yanbin Hu,^a Zhenggen Zha^a and Zhiyong Wang*^a

*Corresponding authors

^aHefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Soft Matter Chemistry and Department of Chemistry & Collaborative Innovation Center of Suzhou Nano Science and Technology, University of Science and Technology of China, Hefei, P. R. China
E-mail: zwang3@ustc.edu.cn
Fax: (+86) 551-360-3185

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00313C

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Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Crystallization of Artemisinin from Chromatography Fractions of Artemisia annua Extract

Crystallization of Artemisinin from Chromatography Fractions ofArtemisia annua Extract

Chandrakant Malwade

Pd(II) pincer type complex catalyzed tandem C-H and N-H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

Pd(II) pincer type complex catalyzed tandem C-H and N-H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

Pd(II) pincer type complex catalyzed tandem C–H and N–H activation of acetanilide in aqueous media: a concise access to functionalized carbazoles in a single step

Catalyst-free thiolation of indoles with sulfonyl hydrazides for the synthesis of 3-sulfenylindoles in water

Catalyst-free thiolation of indoles with sulfonyl hydrazides for the synthesis of 3-sulfenylindoles in water

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