DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO, Worlddrugtracker, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his PhD from ICT ,1991, Mumbai, India, in Organic chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with AFRICURE PHARMA as ADVISOR earlier GLENMARK LS Research centre as consultant,Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Prior to joining Glenmark, he worked with major multinationals like Hoechst Marion Roussel, now sSanofi, Searle India ltd, now Rpg lifesciences, etc. he is now helping millions, has million hits on google on all organic chemistry websites. His New Drug Approvals, Green Chemistry International, Eurekamoments in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 32 year tenure, good knowledge of IPM, GMP, Regulatory aspects, he has several international drug patents published worldwide . He gas good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, polymorphism etc He suffered a paralytic stroke in dec 2007 and is bound to a wheelchair, this seems to have injected feul in him to help chemists around the world, he is more active than before and is pushing boundaries, he has one lakh connections on all networking sites, He makes himself available to all, contact him on +91 9323115463, amcrasto@gmail.com

Dnyaneshwar Gopane, Guest blogger, Novel diarylheptanoids as inhibitors of TNF-α production

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May 062017

Novel diarylheptanoids as inhibitors of TNF-α production

Sameer Dhuru^a, Dilip Bhedi^a, Dnyaneshwar Gophane^a, Kiran Hirbhagat^a, Vijaya Nadar^a, Dattatray More^a, Sapna Parikh^a, Roda Dalal^a, Lyle C. Fonseca^a, Firuza Kharas^a, Prashant Y. Vadnal^a, Ram A. Vishwakarma^a, H. Sivaramakrishnan^a*

^aDepartment of Medicinal Chemistry, Piramal Life Sciences Limited, 1 Nirlon Complex, Off Western Express Highway, Goregaon (E), Mumbai 400 063, India

^bDepartment of Pharmacology, Piramal Life Sciences Limited, 1 Nirlon Complex, Off Western Express Highway, Goregaon (E), Mumbai 400 063, India

Bioorg. Med. Chem. Lett. 21 (2011) 3784–3787

[Link: http://pubs.rsc.org/en/content/articlelanding/2013/cc/c2cc36389e#!divAbstract]

Graphical abstract

Synthesis and anti-inflammatory activity of novel diarylheptanoids [5-hydroxy-1-phenyl-7-(pyridin-3-yl)-heptan-3-ones and 1-phenyl-7-(pyridin-3-yl)hept-4-en-3-ones] as inhibitors of tumor necrosis factor-α (TNF-α production is described in the present article. The key reactions involve the formation of a β-hydroxyketone by the reaction of substituted 4-phenyl butan-2-ones with pyridine-3-carboxaldehyde in presence of LDA and the subsequent dehydration of the same to obtain the α,β-unsaturated ketones. Compounds 4i, 5b, 5d, and 5g significantly inhibit lipopolysaccharide (LPS)-induced TNF-α production from human peripheral blood mononuclear cells in a dose-dependent manner. Of note, the in vitro TNF-α inhibition potential of 5b and 5d is comparable to that of curcumin (a naturally occurring diarylheptanoid). Most importantly, oral administration of 4i, 5b, 5d, and 5g (each at 100 mg/kg) but not curcumin (at 100 mg/kg) significantly inhibits LPS-induced TNF-α production in BALB/c mice. Collectively, our findings suggest that these compounds may have potential therapeutic implications for TNF-α-mediated auto-immune/inflammatory disorders.

Scheme 1. Synthetic scheme

Table 1.

Table 2.

Highlights

Designed and synthesized a novel series of diarylheptanoids.
Compounds 4i, 5b, 5d, and 5g significantly inhibit in vitro TNF-α production from human cells.
Oral administration of these compounds significantly inhibits TNF-α production in mice.
These compounds may have potential therapeutic implications for TNF- α -mediated auto-immune/inflammatory diseases.

ABOUT GUEST BLOGGER

Dr. Dnyaneshwar B. Gophane, Ph. D.

Post doc fellow at Purdue university and university of Iceland

Email, gophane@gmail.com

Dr. Dnyaneshwar B. Gophane completed his B.Sc. (Chemistry) at Anand college of science, Pathardi (Ahmednagar, Maharashtra, India) in 2000 and M.Sc. (Organic Chemistry) at Department of Chemistry, University of Pune (India) in 2003. From 2003 to 2008, he worked in research and development departments of pharmaceutical companies like Dr. Reddy’s Laboratories and Nicholas Piramal India Limited, where he involved in synthesizing novel organic compounds for in vitro and in vivo screening and optimizing process for drug molecule syntheses. In 2008, Dnyaneshwar joined Prof. Sigurdsson’s laboratory for his Ph.D. study at the University of Iceland. His Ph.D. thesis mainly describes syntheses of nitroxide spin-labeled and fluorescent nucleosides and their incorporation into DNA and RNA using phosphoramidite chemistry. These modified nucleosides are useful probes for studying the structure and dynamics of nucleic acids by EPR and fluorescence spectroscopies. In 2014, after finishing his Ph.D., he worked as post doc fellow in same laboratory and mainly worked on spin labelling of RNA. At the university of Purdue in his second post doc, he was totally dedicated to syntheses of small molecules for anti-cancer activity and modification of cyclic dinucleotides for antibacterial activity. During his research experience, he has authored 8 international publications in peer reviewed journals like Chemical Communications, Chemistry- A European Journal, Journal of organic chemistry and Organic and Biomolecular Chemistry.

Dnyaneshwar B. Gophane, Guest blogger, Hydrogen-bonding controlled rigidity of an isoindoline-derived nitroxide spin label for nucleic acids Dnyaneshwar B. Gophane Hydrogen-bonding controlled rigidity of an isoindoline-derived nitroxide spin label for nucleic acids

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May 032017

Hydrogen-bonding controlled rigidity of an isoindoline-derived nitroxide spin label for nucleic acids

Dnyaneshwar B. Gophane and Snorri Th. Sigurdsson*

^a Department of Chemistry, Science Institute, University of Iceland, Dunhaga 3, 107 Reykjavik, Iceland

Chem. Commun., 2013, 49, 999—1001

[Link: http://pubs.rsc.org/en/content/articlelanding/2013/cc/c2cc36389e#!divAbstract]

Graphical abstract

Two new nitroxide-modified nucleosides, ^OxU and ^ImU, were synthesized and incorporated into DNA. ^ImU has lower mobility in duplex DNA due to an intramolecular hydrogen bond.

Abstract

Nucleosides spin-labelled with isoindoline-derived benzimidazole (^ImU) and benzoxazole (^OxU) moieties were synthesized and incorporated into DNA oligonucleotides. Both labels display limited mobility in duplex DNA but ^ImU was less mobile, which was attributed to an intramolecular hydrogen bond between the N-H of the imidazole and O4 of the uracil nucleobase.

Scheme 1. Literature methods for synthesis of diamino isoindoline 6.

Scheme 2. Improved synthesis of diamino isoindoline 6.

Scheme 3. Synthesis of benzimidazole derivative phosphoramidites 10.

str3

Scheme 4. Synthesis of benzoxazole derivative phosphoramidites 14.

Highligts

Synthesized novel nitroxide-labelled benzimidazole (^ImU) and benzoxazole (^OxU) derivatives of 2′-deoxyuridine as spin probes for nucleic acids.
Both ^ImU and ^OxU had limited mobility in duplex DNA, in particular ^ImU, indicating that rotation around the single bond linking the spin label to the uracil is restricted.
^ImU is the first example of using intramolecular hydrogen-bonding to restrict spin label mobility.
^ImU should not only be a good label for accurate distance measurements in oligonucleotides, but also yield information about the relative orientation of the labels.

ABOUT GUEST BLOGGER

Dr. Dnyaneshwar B. Gophane, Ph. D.

Post doc fellow at Purdue university and university of Iceland

Email, gophane@gmail.com

Dr. Dnyaneshwar Gophane

Phone: +917083553405 and +917558215379

These modified nucleosides are useful probes for studying the structure and dynamics of nucleic acids by EPR and fluorescence spectroscopies. In 2014, after finishing his Ph.D., he worked as post doc fellow in same laboratory and mainly worked on spin labelling of RNA. At the university of Purdue in his second post doc, he was totally dedicated to syntheses of small molecules for anti-cancer activity and modification of cyclic dinucleotides for antibacterial activity. During his research experience, he has authored 8 international publications in peer reviewed journals like Chemical Communications, Chemistry- A European Journal, Journal of organic chemistry and Organic and Biomolecular Chemistry.

Dr. D. Srinivasa Reddy has been appointed as an editor of Bioorganic & Medicinal Chemistry Letters, Elsevier Publications.

INDIA Comments Off

May 012017

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

GUEST BLOGGER, Dr Pravin Patil, A New Combination of Cyclohexylhydrazine and IBX for Oxidative Generation of Cyclohexyl Free Radical and Related Synthesis of Parvaquone

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Apr 292017

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As a GUEST BLOGGER, myself Dr Pravin Patil, presenting my paper as below

A New Combination of Cyclohexylhydrazine and IBX for Oxidative Generation of Cyclohexyl Free Radical and Related Synthesis of Parvaquone

Pravin C Patil*^a and Krishnacharya G Akamanchi

Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, Matunga, Mumbai-400 019.

^aPresent address: Department of Chemistry, University of Louisville, Louisville, KY, USA.

*Corresponding Author: Email-pravinchem@gmail.com

Tetrahedron Letters 2017, 58 (19), 1883-1886 (Recently published)

[Link: http://www.sciencedirect.com/science/article/pii/S004040391730429X]

Graphical Abstract:

Abstract: The present paper demonstrate a single-step and straightforward synthesis of parvaquone through intermediacy of cyclohexyl radical generated from novel combination of cyclohexylhydrazine and o-iodoxybenzoic acid and subsequently trapped by 2-hydroxy-1,4-naphthoquinone. Formation of cyclohexyl free radical using this new combination was reaffirmed by cyclohexylation of readily available 2-amino-1, 4-naphthoquinone.

Scheme: Literature methods for synthesis of parvaquone

Scheme: IBX mediated oxidative arylation towards synthesis of 1 (Parvaquone)

Scheme : Cyclohexyl radical mediated postulated mechanism for formation of Parvaquone, 1

Synthesis of 2-cyclohexyl-3-hydroxy-1,4-naphthoquinone (parvaquone) (1): To a solution of 3 (1.0 g, 5.74 mmol) in acetonitrile (20 mL) was added IBX (3.80 g, 13.6 mmol) in one lot and stirred for 5 min at room temperature. To this was added dropwise a solution of 8 (0.78 g, 6.8 mmol) dissolved in 10 mL of acetonitrile over the course of 20 min. During the addition of 8 exotherm (up to 35 °C) was observed with evolution of nitrogen gas in the form of bubbles. Reaction progress was monitored by TLC (using mobile phase, hexane: ethyl acetate/5:95). After satisfactory TLC, water (20 mL) was added to the reaction mixture and acetonitrile was evaporated using rotary evaporator. To the residue obtained was added dichloromethane (30 mL). Oganic layer was separated and washed with saturated sodium bicarbonate solution followed by saturated solution of sodium sulphite. Separated organic layer was dried over anhydrous sodium sulphate and evaporated to obtain crude 1 which was further purified by column chromatography (mobile phase – hexane: ethyl acetate/5:95) to afford 1 as yellow solid, (0.88 g, 60% yield); mp 136-138 °C (lit.¹⁸135-136°C); FT-IR (KBr): 3585, 3513, 3071, 2926, 2853, 1666, 1604, 1590 cm^-1;

¹H NMR (300 MHz; CDCl₃): δ 8.10-8.06 (d, J = 12 Hz, 2H), 7.74-7.67 (d, J = 22 Hz, 2H, 7.45 (s, 1H, OH), 3.11-3.03 (t, J = 16 Hz, 1H), 1.99-1.34 (m, 10H); ¹³C NMR (75 MHz; CDCl₃): δ 184.5, 181.9, 152.8, 135.1, 134.9, 132.7, 129.2, 127.9, 126.9, 125.9, 35.1, 29.2, 26.7, 25.9.

Highlights

New method of generating cyclohexyl radical by using IBX and cyclohexylhydrazine.
Parvaquone synthesized in 60% yield using metal, hazardous peroxide free conditions.
Described method has advantages of single step and mild reaction conditions.
The mechanism for cyclohexyl radical mediated synthesis of parvaquone is postulated.

please note………

Image result for A new combination of cyclohexylhydrazine and IBX for oxidative generation of cyclohexyl free radical and related synthesis of parvaquone

ABOUT GUEST BLOGGER

Dr. Pravin C. Patil

Postdoctoral Research Associate at University of Louisville

see…….http://oneorganichemistoneday.blogspot.in/2017/04/dr-pravin-patil.html

Dr. Pravin C Patil completed his B.Sc. (Chemistry) at ASC College Chopda (Jalgaon, Maharashtra, India) in 2001 and M.Sc. (Organic Chemistry) at SSVPS’S Science College Dhule in North Maharashtra University (Jalgaon, Maharashtra, India) in year 2003. After M.Sc. degree he was accepted for summer internship training program at Bhabha Atomic Research Center (BARC, Mumbai) in the laboratory of Prof. Subrata Chattopadhyay in Bio-organic Division. In 2003, Dr. Pravin joined to API Pharmaceutical bulk drug company, RPG Life Science (Navi Mumbai, Maharashtra, India) and worked there for two years. In 2005, he enrolled into Ph.D. (Chemistry) program at Institute of Chemical Technology (ICT), Matunga, Mumbai, aharashtra, under the supervision of Prof. K. G. Akamanchi in the department of Pharmaceutical Sciences and Technology.

After finishing Ph.D. in 2010, he joined to Pune (Maharashtra, India) based pharmaceutical industry, Lupin Research Park (LRP) in the department of process development. After spending two years at Lupin as a Research Scientist, he got an opportunity in June 2012 to pursue Postdoctoral studies at Hope College, Holland, MI, USA under the supervision of Prof. Moses Lee. During year 2012-13 he worked on total synthesis of achiral anticancer molecules Duocarmycin and its analogs. In 2014, he joined to Prof. Frederick Luzzio at the Department for Chemistry, University of Louisville, Louisville, KY, USA to pursue postdoctoral studies on NIH sponsored project “ Structure based design and synthesis of Peptidomimetics targeting P. gingivalis.

During his research experience, he has authored 23 international publications in peer reviewed journals and inventor for 4 patents.

//////////////Parvaquone, guest blogger, pravin patil

Dr. Vinayak Pagar( GUEST BLOGGER) Development of a Povarov Reaction/Carbene Generation Sequence for Alkenyldiazocarbonyl Compounds

cancer, new drugs, spectroscopy, SYNTHESIS Comments Off

Apr 282017

Discussing my paper……..

Metal-catalyzed cycloadditions of alkenyldiazo reagents are useful tools to access carbo- and heterocycles.[1] These diazo compounds are chemically sensitive toward both Brønsted orLewis acids. Their reported cycloadditions rely heavily on the formation of metal carbenes to initiate regio- and stereoselective [3+n] cycloadditions (n=2–4) with suitable dipolarophiles.[2–4] A noncarbene route was postulated for a few copper-catalyzed cycloadditions of these diazo species, but they resulted in complete diazo decomposition.[3a, 4a, 5] oyle and co-workers reported[4a] a [3+2] cycloaddition of the alkenylrhodium carbene A with imines to give dihydropyrroles (Scheme 1a). We proposed a cycloaddition the tetrahydroquinoline derivatives 3 and 3’, as well as the tetrahydro-1H-benzo[b]azepine species 4. Access to these frameworks are valuable

Access to these frameworks are valuable for the preparation of several bioactive molecules including 2-phenyl-2,3-
dihydroquinolone,[8a] L-689,560,[8b] torcetrapib,[8c] martinellic acid,[8d] OPC-31260,[8e] OPC-51803,[8f] and tetraperalone A (Figure 1).[8g] Their specific biological functions have been well documented.[8]

Spectral data for ethyl 2-diazo-2-(2-phenyl-1,2,3,4-tetrahydroquinolin-4-yl) acetate (2a)

Yellow Semi-Solid;

IR (KBr, cm-1 ): 3542 (m), 2117 (s), 3015 (s), 1737 (s), 1564 (s), 1334 (m), 1137 (s), 817 (s);

1H NMR (600 MHz, CDCl3): δ 7.41 (d, J = 7.3 Hz, 2 H), 7.36 ~ 7.33 (m, 2 H), 7.30 (t, J = 7.3 Hz, 2 H), 7.07 (d, J = 7.6 Hz, 1 H), 7.04 (t, J = 7.6 Hz, 1H), 6.71 (t, J = 7.2 Hz, 1H), 6.55 (d, J = 7.9 Hz, 1H) 4.56 (dd, J = 11.0, 2.3 Hz, 1H ), 4.25 (q, J = 7.1 Hz, 2H ), 4.21 (dd, J = 11.0, 5.3 Hz, 1H ), 4.01 (s, 1H) 2.36 ~ 2.33 (m, 1H), 2.00 (dd, J = 11.8, 2.3 Hz, 1H ), 1.28 (t, J = 7.1 Hz, 3H);

13C NMR (150 MHz, CDCl3): δ 167.2, 145.3, 142.9, 128.6, 128.0, 127.8, 126.5, 126.4, 118.8, 117.9, 114.4, 60.9, 59.5, 56.2, 36.8, 32.6, 14.4.

HRMS calcd for C19H19N3O2: 321.1477; found: 321.1483.

Communication

Development of a Povarov Reaction/Carbene Generation Sequence for Alkenyldiazocarbonyl Compounds^†

Authors, Appaso Mahadev Jadhav, Vinayak Vishnu Pagar, and Rai-Shung Liu*, DOI: 10.1002/anie.201205692

^†We thank the National Science Council, Taiwan, for financial support of this work., [*] A. M. Jadhav, V. V. Pagar, Prof. Dr. R.-S. Liu

Department of Chemistry, National Tsing Hua University
Hsinchu (30013) (Taiwan)
E-mail: rsliu@mx.nthu.edu.tw

Abstract

Rings aplenty: A HOTf-catalyzed (Tf=trifluoromethanesulfonyl) Povarov reaction of alkenyldiazo species has been developed and delivers diazo-containing cycloadducts stereoselectively (see scheme). The resulting cycloadducts provide access to six- and seven-membered azacycles through the generation of metal carbenes as well as the functionalization of diazo group.

[1] Selected reviews: a) M. P. Doyle,M. A. McKervy, T. Ye, Modern Catalytic Methods for Organic Synthesis with Diazo Compounds, Wiley, New York, 1998; b) A. Padwa, M. D. Weingarten, Chem. Rev. 1996, 96, 223; c) H. M. L. Davies, J. R. Denton, Chem. Soc. Rev. 2009, 38, 3061; d) M. P. Doyle, R. Duffy, M. Ratnikov, L. Zhou, Chem. Rev. 2010, 110, 704; e) H. M. L. Davies, D. Morton, Chem. Soc. Rev. 2011, 40, 1857; f) Z. Zhang, J. Wang, Tetrahedron
2008, 64, 6577.
[2] Selected examples for carbocyclic cycloadducts, see: a) L. Deng, A. J. Giessert, O. O. Gerlitz, X. Dai, S. T. Diver, H. M. L. Davies, J. Am. Chem. Soc. 2005, 127, 1342; b) H. M. L. Davies, Adv. Cycloaddit. 1999, 5, 119; c) H. M. L. Davies, B. Xing, N. Kong, D. G. Stafford, J. Am. Chem. Soc. 2001, 123, 7461; d) H. M. L. Davies, T. J. Clark, H. D. Smith, J. Org. Chem. 1991, 56, 3819; e) Y. Liu, K. Bakshi, P. Zavalij, M. P. Doyle, Org. Lett. 2010, 12, 4304; f) J. P. Olson, H. M. L. Davies, Org. Lett. 2008, 10, 573.
[3] For oxacyclic cycloadducts, see: a) X. Xu, W.-H. Hu, P. Y. Zavalij, M. P. Doyle, Angew. Chem. 2011, 123, 11348; Angew. Chem. Int. Ed. 2011, 50, 11152; b) M. P. Doyle, W. Hu, D. J. Timmons, Org. Lett. 2001, 3, 3741.

[4] For azacyclic cycloadducts, see selected reviews: a) M. P. Doyle, M. Yan, W. Hu, L. Gronenberg, J. Am. Chem. Soc. 2003, 125, 4692; b) J. Barluenga, G. Lonzi, L. Riesgo, L. A. Lpez, M. Tomas, J. Am. Chem. Soc. 2010, 132, 13200; c) M. Yan, N. Jacobsen, W. Hu, L. S. Gronenberg, M. P. Doyle, J. T. Colyer, D. Bykowski, Angew. Chem. 2004, 116, 6881; Angew. Chem. Int. Ed. 2004, 43, 6713; d) X.Wang, X. Xu, P. Zavalij, M. P. Doyle, J. Am.
Chem. Soc. 2011, 133, 16402; e) Y. Lian, H. M. L. Davies, J. Am. Chem. Soc. 2010, 132, 440; f) X. Xu, M. O. Ratnikov, P. Y. Zavalij, M. P. Doyle, Org. Lett. 2011, 13, 6122; g) V. V. Pagar, A. M. Jadhav, R.-S. Liu, J. Am. Chem. Soc. 2011, 133, 20728; h) R. P. Reddy, H. M. L. Davies, J. Am. Chem. Soc. 2007, 129, 10312.

[5] Y. Qian, X. Xu, X.Wang, P. Zavalij,W. Hu, M. P. Doyle, Angew. Chem. 2012, 124, 6002; Angew. Chem. Int. Ed. 2012, 51, 5900.
[6] Povarov reactions refer to the formal [4+2] cycloadditions of Naryl imines with enol ethers or enamines. See reviews: a) L. S. Povarov, Russ. Chem. Rev. 1967, 36, 656; b) V. V. Kouznetsov, Tetrahedron 2009, 65, 2721; c) D. Bello, R. Ramn, R. Lavilla, Curr. Org. Chem. 2010, 14, 332; d) M. A. McCarrick, Y. D. Wu, K. N. Houk, J. Org. Chem. 1993, 58, 3330; e) A. Whiting, C. M. Windsor, Tetrahedron 1998, 54, 6035.

[7] For Povarov reactions catalyzed by Brønsted acids, see selected examples: a) H. Xu, S. J. Zuend, M. G. Woll, Y. Tao, E. N. Jacobson, Science 2010, 327, 986; b) T. Akiyama, H. Morita, K. Fuchibe, J. Am. Chem. Soc. 2006, 128, 13070; c) H. Liu, G. Dagousset, G. Masson, P. Retailleau, J. Zhu, J. Am. Chem. Soc. 2009, 131, 4598; d) G. Dagousset, J. Zhu, G. Masson, J. Am. Chem. Soc. 2011, 133, 14804; e) H. Ishitani, S. Kobayashi, Tetrahedron Lett. 1996, 37, 7357; f) G. Bergonzini, L. Gramigna, A. Mazzanti, M. Fochi, L. Bernardi, A. Ricci, Chem. Commun.
2010, 46, 327; g) L. He, M. Bekkaye, P. Retailleau, G. Masson, Org. Lett. 2012, 14, 3158.

[8] a) Y. Xia, Z.-Y. Yang, P. Xia, K. F. Bastow, Y. Tachibana, S.-C. Kuo, E. Hamel, T. Hackl, K.-H. Lee, J. Med. Chem. 1998, 41, 1155; b) R.W. Carling, P. D. Leeson, A. M. Moseley, J. D. Smith, K. Saywell, M. D. Trickelbank, J. A. Kemp, G. R. Marshall, A. C. Foster, S. Grimwood, Bioorg. Med. Chem. Lett. 1993, 3, 65;
c) D. B. Damon, R. W. Dugger, R.W. Scott, U.S. Patent 6,689,897, 2004; d) D. A. Powell, R. A. Batey, Org. Lett. 2002, 4, 2913; e) A. Matsuhisa, K. Kikuchi, K. Sakamoto, T. Yatsu, A. Tanaka, Chem. Pharm. Bull. 1999, 47, 329; f) M. Y. Christopher, E. A. Christine, D. M. Ashworth, J. Barnett, A. J. Baxter, J. D. Broadbridge, R. J. Franklin, S. L. Hampton, P. Hudson, J. A. Horton, P. D. Jenkins, A. M. Penson, G. R.W. Pitt, P. Rivire,
P. A. Robson, D. P. Rooker, G. Semple, A. Sheppard, R. M.Haigh, M. B. Roe, J. Med. Chem. 2008, 51, 8124; g) C. Li, X. Li, R. Hong, Org. Lett. 2009, 11, 4036.

About author( Me)

Dr. Vinayak Pagar

Postdoctoral Research Fellow at The Ohio State University

Vinayak Vishnu Pagar was born in Nasik, Maharashtra (India) in 1983. He obtained his BSc and MSc degrees in chemistry from the University of Pune (India) in 2004 and 2006, respectively. From 2006–2010, he worked as Research Associate in pharmaceutical companies like Jubilant Chemsys Ltd. and Ranbaxy Laboratories Ltd. (India). In 2010, he joined the group of Professor Rai-Shung Liu to pursue his PhD degree in National Tsing Hua University (Taiwan) and completed it in 2014. Subsequently, he worked as a postdoctoral fellow in the same group for one year. Currently, he is working as a Research Scientist at The Ohio State University, Columbus, Ohio USA. His research focused on the development of new organic reactions by using transition-metal catalysis such Gold, Silver, Rhodium, Zinc, Cobalt, Nickel and Copper metals which enables mild, diastereoselective, enantioselective and efficient transformations of variety of readily available substrates to wide range of synthetically useful nitrogen and oxygen containing heterocyclic products which are medicinally important. He published his research in a very high impact factor international Journals includes J. Am. Chem. Soc., Angew. Chem. Int. Ed., J. Org. Chem., Chem- A. Eur. Journal, Org. Biomol. Chem., and Synform (Literature Coverage).

Dr. Vinayak Pagar

Postdoctoral Researcher

Department of Chemistry and Biochemistry

The Ohio State University

100 West 18th Avenue

Columbus, Ohio 43210 USA

vinayak.pagar@gmail.com

/////////Vinayak Pagar, Postdoctoral Research Fellow, The Ohio State University, blog, Povarov Reaction, Carbene Generation Sequence, Alkenyldiazocarbonyl Compounds

Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile

spectroscopy, SYNTHESIS Comments Off

Apr 222017

Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile

Green Chem., 2017, Advance Article

DOI: 10.1039/C7GC00602K, Communication

Katharina J. Hock, Robin Spitzner, Rene M. Koenigs
Applications of diazo acetonitrile in cyclopropa(e)nation reactions are realized in a slow-release protocol with bench-stable reagents. Cyclopropyl nitriles are obtained in one step in good diastereoselectivity on a gram-scale providing an efficient entry into this class of fragrances and drug-like molecules.

trans-2-phenylcyclopropane-1-carbonitrile

colorless solid (46 mg, 81%);

m.p. = 29°C;

1 H-NMR (600 MHz, CDCl3): δ = 7.34 – 7.30 (m, 2H), 7.28 – 7.24 (m, 1H), 7.12 – 7.08 (m, 2H), 2.63 (ddd, J = 9.2, 6.7, 4.7 Hz, 1H), 1.62 (dt, J = 9.2, 5.4 Hz, 1H), 1.55 (ddd, J = 8.7, 5.5, 4.8 Hz, 1H), 1.45 (ddd, J = 8.8, 6.7, 5.3 Hz, 1H);

13C-NMR (151 MHz, CDCl3): δ = 137.55, 128.76, 127.41, 126.31, 121.05, 24.90, 15.24, 6.63;

HRMS (ESI): m/z calc. for [C10H9NNa]: 166.06272, found 166.06276;

IR (KBr): νmax/cm-1 = 3044, 2235, 2098, 1761, 1600, 1461, 1220, 1051, 920, 705.

The analytical data is in correspondence with the literature [2]

[2] M. Gao, N. N. Patwardhan, P. R. Carlier, J. Am. Chem. Soc., 2013, 135 (38), 14390–14400

http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C7GC00602K?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

Towards nitrile-substituted cyclopropanes – a slow-release protocol for safe and scalable applications of diazo acetonitrile

Katharina J. Hock,^a Robin Spitzner^a and Rene M. Koenigs*^a

Author affiliations

*Corresponding authors

^aRWTH Aachen University, Institute of Organic Chemistry, Landoltweg 1, D-52074 Aachen, Germany
E-mail: rene.koenigs@rwth-aachen.de

Abstract

Diazo acetonitrile has long been neglected despite its high value in organic synthesis due to a high risk of explosions. Herein, we report our efforts towards the transient and safe generation of this diazo compound, its applications in iron catalyzed cyclopropanation and cyclopropenation reactions and the gram-scale synthesis of cyclopropyl nitriles.

//////////

Dimethylcarbamoyl Chloride, a known carcinogen

PROCESS Comments Off

Mar 142017

Identifiers

CAS Number	79-44-7
ECHA InfoCard	100.001.099
PubChem	6598
Properties
Chemical formula	C₃H₆ClNO

Dimethylcarbamoyl Chloride

Mechanisms for the Formation of Dimethylcarbamoyl Chloride

Thionyl chloride is the most common reagent in process chemistry for the conversion of a carboxylic acid to an acid chloride. One of the primary factors is cost, since the reagent is inexpensive and represents one of the most cost-efficient ways of preparing acid chlorides. However, one disadvantage of thionyl chloride is the potential formation of dimethylcarbamoyl chloride, a known carcinogen in animal models, when used in combination with DMF as catalyst.

Dimethylcarbamoyl chloride is a reagent for transferring a dimethylcarbonyl group to alcoholic or phenolic hydroxyl groups forming dimethyl carbamates, usually having pharmacological or pesticidal activities. Because of its high toxicity and its carcinogenic properties shown in animal experiments and presumably also in humans,^[1] dimethylcarbamoyl chloride can only be used under stringent safety precautions.

Production and occurrence

The production of dimethylcarbamoyl chloride from phosgene and dimethylamine (DMA) was reported as early as 1879 (reported as “Dimethylharnstoffchlorid” – dimethylurea chloride).^[2]

Dimethylcarbamoyl chloride can be produced in high yields (90%) at 275 °C by reacting phosgene with gaseous dimethylamine in a flow reactor.^[3] To suppress the formation of ureas excessive phosgene is used (in a 3:1 ratio).

The reaction can also be carried out at the laboratory scale with diphosgene or triphosgene and a aqueous dimethylamine solution in the two-phase system benzene+xylene/water in a stirred reactor with sodium hydroxide as an acid scavenger. However, considerably lower yields (56%) are achieved due to the hydrolysis sensitivity of dimethylcarbamoyl chloride .^[4]

Dimethylcarbamoyl chloride is also formed (together with methyl chloride) when reacting phosgene with trimethylamine.^[5]

A more recent process is based on dimethylamine chloride, which is converted practically quantitatively to dimethylcarbamoyl chloride on a palladium catalyst under pressure with carbon monoxide at room temperature.^[6]

Dicarbamoyl chloride can also be formed in small amounts (0-20 ppm) from dimethylformamide (DMF) in the Vilsmeier-Haack reaction^[7] or when DMF is used as a catalyst in the reaction of carboxylic acids with thionyl chloride to the corresponding carboxylic acid chlorides.^[8]

The tendency towards dicarbamoyl chloride formation depends on the chlorination reagent (thionyl chloride> oxalyl chloride> phosphorus oxychloride) and is higher in the presence of a base. However, dicarbamoyl chloride hydrolyses very quickly to dimethylamine, hydrochloric acid and carbon dioxide (with a half-life of about 6 minutes at 0 °C) so that less than 3 ppm of dicarbamoyl chloride are found in the Vilsmeier product after aqueous work-up.^[9]

Properties[edit]

Dimethylcarbamoyl chloride is a clear, colorless, corrosive and flammable liquid with a pungent odor and a tear-penetrating effect, which decomposes rapidly in water.^[10]Because of its unpleasant, toxic, mutagenic and carcinogenic properties^[11]^[12] it has to be used under extreme precautions.

Dimethylcarbamoyl chloride behaves like an acid chloride whose chlorine atom can be exchanged for other nucleophiles. Therefore, it reacts with alcohols, phenols and oximes to the corresponding N, N-dimethylcarbamates, with thiols to thiolourethanes, with amines and hydroxylamine to substituted ureas, and with imidazoles and triazoles to carbamoylazoles.^[13]

Dimethylcarbamoyl chloride is less reactive and less selective to substrates with multiple nucleophilic centers than conventional acid chlorides.

Unsaturated conjugated aldehydes such as (2E)-butenal react with dimethylcarbamoyl chloride forming dienyl carbamates, which can be used as dienes in Diels-Alder reactions.^[14]

Alkali metal carboxylates react with dimethylcarbamoyl chloride forming the corresponding dimethylamides. Dimethylcarbamoyl chloride reacts with anhydrous sodium carbonate^[15] or with excess dimethylamine to tetramethylurea.^[16]

The reaction of dimethylcarbamoyl chloride with DMF forms tetramethylformamidinium^[17] chloride which is a major intermediate in the preparation of tris(dimethylamino)methane, a reagent for the introduction of enamine functions in conjunction with activated methylene groups^[18] and the preparation of amidines.^[19]

Dimethylcarbamoyl chloride is a starting material for the insecticide class of the dimethyl carbamates^[20] which act as inhibitors of acetylcholinesterase, including dimetilane,^[21]and the related compounds isolane, pirimicarb and triazamate.

The quaternary ammonium compounds neostigmine^[22] finds pharmaceutical applications as acetylcholinesterase inhibitors. It is obtained from 3-dimethylaminophenol and dimethylcarbamoyl chloride and subsequent quaternization with methyl bromide or dimethyl sulfate^[23]

and pyridostigmine, which is obtainable from 3-hydroxypyridine and dimethylcarbamoyl chloride and subsequent reaction with methyl bromide.^[24]

Dimethylcarbamoyl chloride is also used in the synthesis of the benzodiazepine camazepam.^[25]

Image result for Dimethylcarbamoyl Chloride

13c NMR

MASS

RAMAN

References

Jump up^ R.P. Pohanish (2011) (in German), Sittig’s Handbook of Toxic and Hazardous Chemicals and Carcinogens, 6th Edition, Amsterdam: Elsevier, pp. 1045–1047, ISBN 978-1437778694
Jump up^ W. Michler; C. Escherich (1879), “Ueber mehrfach substituirte Harnstoffe” (in German), Ber. Dtsch. Chem. Ges. 12 (1): pp. 1162–1164, doi:10.1002/cber.187901201303
Jump up^ R.J. Slocombe; E.A. Hardy; J.H. Saunders; R.L. Jenkins (1950), “Phosgene derivatives. The preparation of isocyanates, carbamyl chlorides and cyanuric acid” (in German), J. Am. Chem. Soc. 72 (5): pp. 1888–1891, doi:10.1002/ja01161a009
Jump up^ G. Karimipour; S. Kowkabi; A. Naghiha (2015), “New aminoporphyrins bearing urea derivative substituents: synthesis, characterization, antibacterial and antifungal activity” (in German), Braz. Arch. Biol. Technol. 58 (3), doi:10.1590/S1516-891320500024
Jump up^ H. Babad; A.G. Zeiler (1973), “Chemistry of Phosgene” (in German), Chem. Rev. 73 (1): pp. 75–91, doi:10.1021/cr60281a005
Jump up^ T. Saegusa; T. Tsuda; Y. Isegawa (1971), “Carbamoyl chloride formation from chloramine and carbon monoxide” (in German), J. Org. Chem. 36 (6): pp. 858–860, doi:10.1021/jo00805a033
Jump up^ M. Stare; K. Laniewski; A. Westermark; M. Sjögren; W. Tian (2009), “Investigation on the formation and hydrolysis of N,N-dimethylcarbamoyl chloride (DMCC) in Vilsmeier reactions using /GC/MS as the analytical detection method” (in German), Org. Process Res. Dev. 13 (5): pp. 857–862, doi:10.1021/op900018f
Jump up^ D. Levin (1997), “Potential toxicological concerns associated with carboxylic acid chlorination and other reactions” (in German), Org. Process Res. Dev. 1 (2): pp. 182, doi:10.1021/op970206t
Jump up^ A. Queen (1967), “Kinetics of the hydrolysis of acyl chlorides in pure water” (in German), Canad. J. Chem. 45 (14): pp. 1619–1629, doi:10.1139/v67-264
Jump up^ C.B. Kreutzberger; R.A. Olofson (2001), “Dimethylcarbamoyl Chloride” (in German), e-EROS Encyclopedia of Reagents for Organic Synthesis, doi:10.1002/047084289X.rd319
Jump up^ P. Jäger; C.N. Rentzea; H. Kieczka (2014) (in German), Carbamates and Carbamoyl Chloride, in Ullmann’s Fine Chemicals, Weinheim: Wiley-VCH, pp. 57–58, ISBN 978-3-527-33477-3
Jump up^ “Dimethylcarbamoyl Chloride, CAS No. 79-44-7” (PDF). Report on Carcinogens, Thirteenth Edition (in German). National Toxicology Program, Department of Health and Human Services. Retrieved 2016-09-25.
Jump up^ C.B. Kreutzberger, R.A. Olofson (2007-02-01). “Dimethylcarbamoyl Chloride” (in German). John Wiley&Sons, Ltd. Retrieved 2016-09-27.
Jump up^ P.F. De Cusati; R.A. Olofson (1990), “A simple synthesis of 1-(1,3-butadienyl)carbonates and carbamates” (in German), Tetrahedron Lett. 31 (10): pp. 1405–1408, doi:10.1016/S0040-4039(00)88817-6
Jump up^ J.K. Lawson Jr.; J.A.T. Croom (1963), “Dimethylamides from alkali carboxylates and dimethylcarbamoyl chloride” (in German), J. Org. Chem. 28 (1): pp. 232–235, doi:10.1021/jo1036a513
Jump up^ US 3597478, M.L. Weakly, “Preparation of tetramethylurea”
Jump up^ Z. Arnold (1959), “The preparation of tetramethylformamidinium salts and their vinylogues” (in German), Coll. Czech. Chem. Commun. 24: pp. 760–765, doi:10.1135/cccc19590760
Jump up^ H. Meerwein; W. Florian; N. Schön; G. Stopp (1961), “Über Säureamidacetale, Harnstoffacetale und Lactamacetale” (in German), Justus Liebigs Ann. Chem. 641 (1): pp. 1–39, doi:10.1002/jlac.19616410102
Jump up^ H. Bredereck; F. Effenberger; Th. Brendle (1966), “Synthese und Reaktionen von Trisdimethylaminomethan” (in German), Angew. Chem. 78 (2): pp. 147–148, doi:10.1002/ange.19660780212
Jump up^ “Compendium of Pesticide Common Names” (in German). Alan Wood. Retrieved 2016-09-27.
Jump up^ US 3452043, T. Grauer, H. Urwyler, “Production of 1-N,N-dimethylcarbamoyl-5-methyl-3-N,N-dimethyl-carbamoyl-oxy-pyrazole”
Jump up^ J.A. Aeschlimann; M. Reinert (1931), “Pharmacological action of some analogues of physostigmine” (in German), J. Pharmacol. Exp. Ther. 43 (3): pp. 413–444
Jump up^ US 1905990, J.A. Aeschlimann, “Disubstituted carbamic acid esters of phenols containing a basic constituent”
Jump up^ US 2572579, “Disubstituted carbamic acid esters of 3-hydroxy-1-alkyl-pyridinium salts”
Jump up^ DOS 2448015, “Verfahren zur Herstellung des 3-N,N-Dimethylcarbamoyl-oxy-1-methyl-5-phenyl-7-chlor-1,3-dihydro-2H-1,4-benzodiazepin-2-on”

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Cholecystokinin-2/gastrin antagonists: 5-hydroxy-5-aryl-pyrrol-2-ones as anti-inflammatory analgesics for the treatment of inflammatory bowel disease

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Mar 132017

Cholecystokinin-2/gastrin antagonists: 5-hydroxy-5-aryl-pyrrol-2-ones as anti-inflammatory analgesics for the treatment of inflammatory bowel disease

Med. Chem. Commun., 2017, Advance Article
DOI: 10.1039/C6MD00707D, Research Article

E. Lattmann, J. Sattayasai, R. Narayanan, N. Ngoc, D. Burrell, P. N. Balaram, T. Palizdar, P. Lattmann
Arylated 5-hydroxy-pyrrol-2-ones were prepared in 2 synthetic steps from mucochloric acid and optimised as CCK₂-selective ligands using a range of assays.

Cholecystokinin-2/gastrin antagonists: 5-hydroxy-5-aryl-pyrrol-2-ones as anti-inflammatory analgesics for the treatment of inflammatory bowel disease

E. Lattmann,*^a J. Sattayasai,^b R. Narayanan,^c N. Ngoc,^a D. Burrell,^a P. N. Balaram,^d T. Palizdar^a and P. Lattmann^d

*Corresponding authors

^aSchool of Life and Health Sciences, Aston University, Aston Triangle, Birmingham B4 7ET, UK
E-mail: e.lattmann@aston.ac.uk

^bDepartment of Pharmacology, Faculty of Medicine, Khon Kaen University, 40002 Khon Kaen, Thailand

^cDepartment of Medicine, University of Tennessee Health Science Center, Memphis, USA

^dPNB Vesper Life Science PVT, Cochin, India

Med. Chem. Commun., 2017, Advance Article

DOI: 10.1039/C6MD00707D

Arylated 5-hydroxy-pyrrol-2-ones were prepared in 2 synthetic steps from mucochloric acid and optimised as CCK₂-selective ligands using radiolabelled binding assays. CCK antagonism was confirmed for the ligands in isolated tissue preparations. DSS (dextran sulfate sodium)-induced inflammation was analysed for derivative 7 and PNB-001 with L-365,260 as a standard. The IC₅₀ of PNB-001 was determined to be 10 nM. Subsequent in vivo evaluation confirmed anti-inflammatory activity with respect to IBD assays. The best molecule, PNB-001, showed analgesic activity in the formalin test and in the hotplate assay, in which the analgesic effect of 1.5 mg kg⁻¹ PNB-001 was equivalent to 40 mg kg⁻¹ tramadol. The CCK₂-selective antagonist PNB-001 protected rats against indomethacin-induced ulceration at similar doses. The GI protection activity was found to be more potent than that of the 10 mg kg⁻¹ dose of prednisolone, which served as a standard.

General Method: The relevant amine (2.5 times excess) was added to a solution of lactone A – E (0.7 mol) in ether (10 ml) and stirred on ice for 30 minutes, allowing to warm up to RT over the time. The resultant mixture was poured into 5 ml water and separated by separating funnel. The mixture was washed with water three times. The organic layer was dried over magnesium sulphate and the solvent was removed under vacuum. All compounds gave an oily solid which were passed through a column (80% ether, 20% petrol ether). The resulting fractions were dried from excess solvent under vacuum to yield crystals. 4-Chloro-1-cyclopropyl-5-hydroxy-5-phenyl-1,5-dihydro-pyrrol-2-one 1 Yield = 83 %; mp: 177-179 oC;

MS (APCI(+)): 193/195 (M+1), 250/252 (M+) m/z

1H NMR (CDCl3) 250 MHz:  = 7.41 (m, 5H), 6.09 (s, 1H), 3.50 (m, 1H), 2.18 (m, 1H), 0.95-1.04 & 0.38-0.69 (m, 4H);

13C NMR (CDCl3) 167.4, 154.8, 135.2, 129.2, 128.8, 126.1, 122.2, 93.5, 22.6 , 3.8, 5.1;

IR (KBr-disc)  max: 3416, 3260, 3105, 3011, 2363, 2338, 1671, 1602, 1490, 1450, 1409, 1369, 1256, 1144, 1032, 939, 833, 752, 702 cm-1 .

/////////////////Cholecystokinin-2/gastrin antagonists, 5-hydroxy-5-aryl-pyrrol-2-ones, anti-inflammatory analgesics, inflammatory bowel disease

Award for me, 100 Most Impactful Health care Leaders, Global listing

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Feb 142017

str6

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

tert-butyl(3aR,6aS)-5-oxohexahydrocyclopenta[c]pyrrole-2(1H)-carboxylate

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Feb 092017

Abstract Image

tert-butyl(3aR,6aS)-5-oxohexahydrocyclopenta[c]pyrrole-2(1H)-carboxylate

tert-Butyl (3aR,6aS)-5-Oxohexahydrocyclopenta[c]pyrrole-2(1H)-carboxylate (1)

pure compound 1 (1.051 kg, 67%) as a white solid. Mp: 70–71 °C (uncorrected); [α]²⁵_D +0.40° (c 1.00 CHCl₃); % purity: 98.5% (HPLC);

¹H NMR (CDCl₃, 400 MHz) δ: 1.46 (s, 9H), 2.15 (dd, J₁ = 4.8 Hz, J₂ = 19.6 Hz, 2H), 2.47 (dd, J₁ = 7.4 Hz, J₂ = 19.6 Hz, 2H), 2.93 (bs, 2H), 3.16–3.28 (m, 2H), 3.65–3.67 (m, 2H).;

¹³C NMR (CDCl₃, 100 MHz) δ: 38.49, 39.36, 42.32, 50.51, 50.77, 79.49, 154.39, 217.65; IR (KBr): ν = 638, 771, 877, 1118, 1166, 1247, 1367, 1402, 1691, 1741, 2877, 2910, 2958, 2976, 3005 cm^–1;

TOFMS: [C₁₂H₁₉NO₃ + H⁺]: calculated 226.1438, found 152.0663 (M-OtBu)⁺ (100%), 170.0755 (M-tBu + H)⁺ (40%), 248.1166 (M + Na)⁺ (5%).

Anal. Calcd for C₁₂H₁₉NO₃: C, 63.98; H, 8.50; N, 6.22. Found: C, 63.89; H, 8.27; N, 5.97.

HPLC conditions were as follows for compound ; Agilent 1100 series, column: YMC J’SPHERE C18 (150 mm X 4.6 mm) 4µm with mobile phases A (0.05% TFA in water) and B (acetonitrile). Detection was at 210 nm, flow was set at 1.0 mL/min, and the temperature was 30 °C (Run time: 45 min). Gradient: 0 min, A = 90%, B = 10%; 5.0 min, A = 90%, B = 10%; 25 min, A = 0%, B = 100%; 30 min, A = 0%, B = 100%, 35 min, A = 90%, B = 10%; 45 min, A = 90%, B = 10%.

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.6b00399

http://pubs.acs.org/doi/full/10.1021/acs.oprd.6b00399

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