ENDO EXO STORY.......cis-norborene-5,6-endo-dicarboxylic anhydride

ENDO EXO STORY.......cis-norborene-5,6-endo-dicarboxylic anhydride

You will react cyclopentadiene with maleic anhydride to form the Diels-Alder product below. This Diels-Alder reaction produces almost solely the endo isomer upon reaction at ambient temperature.




The preference for endo–stereochemistry is “observed” in most Diels-Alder reactions. The fact that the more hindered endo product is formed puzzled scientists until Woodward, Hoffmann, and Fukui used molecular orbital theory to explain that overlap of the p orbitals on the substituents on the dienophile with p orbitals on the diene is favorable, helping to bring the two molecules together.

Hoffmann and Fukui shared the 1981 Nobel Prize in chemistry for their molecular orbital explanation of this and other organic reactions. In the illustration below, notice the favorable overlap (matching light or dark lobes) of the diene and the substituent on the dienophile in the formation of the endo product:






Oftentimes, even though the endo product is formed initially, an exo isomer will be isolated from a Diels-Alder reaction. This occurs because the exo isomer, having less steric strain than the Endo , is more stable, and because the Diels-Alder reaction is often reversible under the reaction conditions. In a reversible reaction, the product is formed, reverts to starting material, and forms again many times before being isolated.

The more stable the product, the less likely it will be to revert to the starting material. The isolation of an exo product from a Diels-Alder reaction is an example of an important concept: thermodynamic vs kinetic control of product composition. The first formed product in a reaction is called the kinetic product. If the reaction is not reversible under the conditions used, the kinetic product will be isolated. However, if the first formed product is not the most stable product and the reaction is reversible under the conditions used, then the most stable product, called the thermodynamic product, will often be isolated.



The NMR spectrum of cis-5-norbornene-2,3-endo-dicarboxylic anhydride is given below:





Cis-Norbornene-5,6-endo-dicarboxylic anhydride 
Cyclopentadiene was previously prepared through the cracking of dicyclopentadiene and kept under cold conditions.  In a 25 mL Erlenmeyer flask, maleic anhydride (1.02 g, 10.4 mmol) and ethyl acetate (4.0 mL) were combined, swirled, and slightly heated until completely dissolved.  To the mixture, ligroin (4 mL) was added and mixed thoroughly until dissolved.  Finally, cyclopentadiene (1 mL, 11.9 mmol) was added to the mixture and mixed extensively.  The reaction was cooled to room temperature and placed into an ice bath until crystallized.  The crystals were isolated through filtration in a Hirsch funnel.  The product had the following properties: 0.47 g (27.6% yield) mp: 163-164 °C (lit: 164 °C).  ¹H NMR (CDCl₃, 300 MHz) δ: 6.30 (dd, J=1.8 Hz, 2H), 3.57 (dd, J=7.0 Hz, 2H), 3.45 (m, 2H), 1.78 (dt, J=9.0,1.8 Hz, 1H), 1.59 (m, 1H) ppm.  ¹³C NMR (CDCl₃, 75Hz) δ: 171.3, 135.5, 52.7, 47.1, 46.1 ppm.  IR 2982 (m), 1840 (s), 1767 (s), 1089 (m) cm^-1.

Reaction Mechanism The scheme below depicts the concerted mechanism of the Diels-Alder reaction of cyclopentadiene and maleic anhydride to formcis-Norbornene-5,6-endo-dicarboxylic anhydride.

Results and Discussion 
When combining the reagents, a cloudy mixture was produced and problems arose in the attempt to completely dissolve the mixture.  After heating for about 10 minutes and magnetically stirring, tiny solids still remained. The undissolved solids were removed form the hot solution by filtration and once they cooled, white crystals began to form. Regarding the specific reaction between cyclopentadiene and maleic anhydride, the endo isomer, the kinetic product, was formed because the experiment was directed under mild conditions.   The exo isomer is the thermodynamic product because it is more stable.3

A total of 0.47 g of the product was collected; a yield of 27.6%. The melting point was in the range of 163-164 °C which indicates the absence of impurities because the known melting point of the product is 164 °C.

The ¹H NMR spectrum of the product revealed a peak in the alkene range at 6.30 ppm, H-2 and H-3 (Figure 1).  In addition, it exhibited two peaks at 3.57 and 3.45 ppm because of the proximity of H-1, H-4, H-5, and H-6 to an electronegative atom, oxygen.  Finally, two peaks at 1.78 and 1.59 ppm corresponded to the sp³ hydrogens, Hb and Ha, respectively.  Impurities that appeared included ethyl acetate at 4.03, 2.03, and 1.31 ppm as well as acetone at 2.16 ppm.

Regarding the ¹³C NMR, a peak appeared at 171.3 ppm, accounting for the presence of two carbonyl functional groups, represented by C-7 and C-8 in Figure 1.  The alkene carbons, C-2 and C-3, exhibited a peak at 135.5 ppm, while the sp³ carbons close to oxygen, C-5 and C-6, displayed a peak at 52.7 ppm.  Finally, peaks at 46.1 and 47.1 ppm accounted for the sp³ carbons, C-1 and C-4, and C-9.  Impurities of ethyl acetate appeared at 46.6, 25.8, and 21.0 ppm accompanied with acetone at 30.9 ppm.

The IR spectrum revealed a peak at 2982 cm^-1 representing the C-H stretches.  A peak at 1840 cm^-1 accounted for the carbonyl functional group, while a peak at 1767 cm^-1 accounted for the alkene bond.  A peak at 1089 cm^-1 represented the carbon-oxygen functional group.

In order to distinguish between the two possible isomers, properties such as melting point and spectroscopy data were analyzed.  The exo product possessed a melting point in the range of 140-145 °C which is significantly lower than the endo product.  The observed melting point in this experiment supported the production of the endo isomer. 
The ¹H NMR spectum exhibited a doublet of doublets at 3.57 ppm for the endo isomer.  The exo isomer would possess a triplet around 3.50 ppm due to the difference in dihedral angle between the hydrogen molecules of H-1 and H-4, and H-5 and H-6 (Figure 1).  A peak at 3.00 ppm would appear in the exo isomer spectra as opposed to a peak at 3.60 ppm as shown in the observed endo product.³ This is because of the interaction and coupling with the H-5 and H-6, as displayed in Figure 1.

Conclusion 
Through the Diels-Alder reaction, 27.6% yield of cis-Norbornene-5,6-endo-dicarboxylic anhydride was produced. The distinction of the presence of the endo isomer was proven by analyzing physical properties of both possible isomers.

Martin, J.; Hill, R.; Chem Rev, 1961, 61, 537-562.

2 Pavia, L; Lampman, G; Kriz, G; Engel, R. A Small Scale Approach to Organic Laboratory   Techniques, 2011, 400-409.

3 Myers, K.; Rosark, J. Diels-Alder Synthesis, 2004, 259-265.
link 
http://orgspectroscopyint.blogspot.in/2014/08/cis-norborene-56-endo-dicarboxylic.html

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DR ANTHONY MELVIN CRASTO Ph.D

amcrasto@gmail.com

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Hemicellulose-derived chemicals: one-step production of furfuryl alcohol from xylose

Hemicellulose-derived chemicals: one-step production of furfuryl alcohol from xylose

 

 

 

 

 

Green Chem., 2014, 16,3942-3950
DOI: 10.1039/C4GC00398E, Paper

Rafael F. Perez^a and   Marco A. Fraga*^a  

*

Corresponding authors

^a

Instituto Nacional de Tecnologia/MCTI, Divisão de Catálise e Processos Químicos, Av. Venezuela, 82/518, Centro, Rio de Janeiro, Brazil 
E-mail: marco.fraga@int.gov.br

This study reports an innovative process to obtain furfuryl alcohol from xylose over a dual heterogeneous catalyst system that allows the reaction to occur in a single step. The presence of acid and metal sites is mandatory to promote the dehydration of xylose to furfural and its hydrogenation to furfuryl alcohol. The composition of solvent is decisive in determining the selectivity.

 One-pot production of furfuryl alcohol via xylose dehydration followed by furfural hydrogenation was investigated over a dual catalyst system composed of Pt/SiO₂ and sulfated ZrO₂ as metal and acid catalysts, respectively. All samples were characterized by XRD, XRF, N₂ physisorption, TG-MS and FTIR regarding their most fundamental properties for the studied process. A systematic study is reported on the effects of the reaction temperature, the composition of the binary solvent and the molar ratio between acid and metal sites in the catalyst system. The results revealed the feasibility of the one-step process for furfuryl alcohol synthesis and showed that the occurrence of both acid and metal sites is compulsory in order to promote the dehydration of xylose to furfural and its further hydrogenation to furfuryl alcohol. Selectivity towards furfuryl alcohol was found to be strongly dependent on the solvent, which can inhibit its polymerization to some extent.

http://pubs.rsc.org/en/Content/ArticleLanding/2014/GC/C4GC00398E?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

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Combination of Pd/C and Amberlyst-15 in a single reactor for the acid/hydrogenating catalytic conversion of carbohydrates to 5-hydroxy-2,5-hexanedione

Combination of Pd/C and Amberlyst-15 in a single reactor for the acid/hydrogenating catalytic conversion of carbohydrates to 5-hydroxy-2,5-hexanedione

 

 

 

Green Chem., 2014, Advance Article
DOI: 10.1039/C4GC01158A, Communication

Fei liu,^a   Maïté Audemar,^a   Karine De Oliveira Vigier,^a  Jean-Marc Clacens,^b   Floryan De Campo^b and  François Jérôme*^a  

Hide Affiliations

*

Corresponding authors

^a

Institut de Chimie des Milieux et Matériaux de Poitiers, ENSIP, Université de Poitiers, 1 rue Marcel Doré, 86022 Poitiers, France 
E-mail: francois.jerome@univ-poitiers.fr

^b

Eco-Efficient Products and Processes Laboratory, UMI 3464 CNRS/Solvay, 3966 Jin Du Road, Shanghai 201108, China 
E-mail: floryan.decampo@solvay.com

Here we show that combination of Pd/C and Amberlyst-15 in a single reactor allowed fructose and inulin to be converted to 5-hydroxy-2-5-hexanedione, a valuable chemical platform, in a one-pot process.
http://pubs.rsc.org/en/Content/ArticleLanding/2014/GC/C4GC01158A?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract
Here we report an effective cooperation between Pd/C and Amberlyst-15 for the catalytic conversion of fructose and inulin to 5-hydroxymethyl-2,5-hexanedione in a one-pot process.

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Catalyst-free sulfonylation of activated alkenes for highly efficient synthesis of mono-substituted ethyl sulfones in water

Catalyst-free sulfonylation of activated alkenes for highly efficient synthesis of mono-substituted ethyl sulfones in water

Green Chem., 2014, Advance Article
DOI: 10.1039/C4GC00932K, Communication

Yu Yang,^a   Lin Tang,^a   Sheng Zhang,^a   Xuefeng Guo,^a  Zhenggen Zha^a and   Zhiyong Wang*^a   

 

*

Corresponding authors

^a

Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Soft Matter 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., 2014, Advance Article

DOI: 10.1039/C4GC00932K

A catalyst-free sulfonylation of activated alkenes developed under mild conditions in water.

 

 

http://pubs.rsc.org/en/Content/ArticleLanding/2014/GC/C4GC00932K?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

 

 

  

A catalyst-free sulfonylation reaction of activated alkenes with sulfonyl hydrazides was efficiently developed under mild and environmentally benign conditions, in water without any ligand or additive. The reaction gave a range of structurally diverse mono-substituted ethyl sulfones with excellent yields, in which the by-product was nitrogen.

Oleanolic acid spectral data and interpretation

Oleanolic acid spectral data and interpretation

Oleanolic acid
(4aS,6aR,6aS,6bR,8aR,10S,12aR,14bS)-10-hydroxy-2,2,6a,6b,9,9,12a-heptamethyl-1,3,4,5,6,6a,7,8,8a,10,11,12,13,14b-tetradecahydropicene-4a-carboxylic acid

see full interpretation, 1H NMR, 13C NMR at

http://orgspectroscopyint.blogspot.in/2014/08/oleanolic-acid-spectral-data-and.html

Total Syntheses of Leuconoxine, Leuconodine B, and Melodinine E by Oxidative Cyclic Aminal Formation and Diastereoselective Ring-Closing Metathesis

read all
 http://chemistrycorey.blogspot.in/2014/05/total-syntheses-of-leuconoxine.html

Bishydrazide to Synthesize oxadiazoles......Important drugs

Bishydrazide to Synthesize oxadiazoles

Drugs containing 1, 3, 4-oxadiazole moiety

http://www.pharmatutor.org/articles/Chemistry-common-synthetic-route-oxadiazole-%20important-heterocyclic-moiety-in-medicinal-chemistry?page=0,5

http://www.pharmatutor.org/articles/Chemistry-common-synthetic-route-oxadiazole-%20important-heterocyclic-moiety-in-medicinal-chemistry?page=0,0

Novel 2-amino-5-substituted-1,3,4-oxadiazoles have been synthesized in excellent yields using the synthetic route outlined in Scheme 1. IR, ¹H NMR, ¹³C NMR and mass spectral data are in agreement with the proposed structures of all synthesized compounds. 

Lack of ¹H NMR resonances observed with NH and NH₂ functions in the¹H NMR spectrum of 1a-n proved that ring closure starting from 4 resulted in the formation of 2-amino-1,3,4-oxadiazole ring. 

This was further substantiated by the ¹³C NMR data of 1 which showed the peaks at 8 170-173 and 145-150 due to C₂ and C₅ of oxadiazole respectively. The IR spectrum shows 1600-1620 ern¹ for (C=N-N=C) and 1063-1073 cm^-1 for (C-O-C) in the compounds 1a-1n which confirmed the synthesis of 1,3,4-oxadiazoles.

http://www.scielo.cl/scielo.php?pid=S0717-97072010000100030&script=sci_arttext

1,3,4-oxadiazole is a versatile lead molecule for designing potential bioactive agents. The 1,3,4-oxadiazole derivatives have been found to exhibit diverse biological activities such as hypotensive¹ anti-microbial^2-4, anti-HIV^2-4, anti-fungal^5-6 anti-inflammatory⁷ antimitotic activity⁸ and muscle relaxant⁹

It have been found in the líterature study that the methods for synthesis of oxadiazole 1 include bromine oxidation of semicarbazide derivative and the cyclodesulfurization of acylthiosemicarbazide derivatives in the solution using I₂/NaOH or 1,3-dicyclohexylcarbodimide (DCC)^10-13 as well as mercury(II) acetate (Hg(OAc)₂) or yellow mercury(II) oxide HgO^14-16 Evans¹⁷ synthesized oxadiazole derivatives by rapid parallel synthesis in efficient one-pot preparation using resin-bound reagents. All these methods are usually carried out in various different synthetic steps and require the heating at higher temperature. The handling of these reagents is not only difficult but also very hazardous to environment. The each stage of the reaction including extraction and purification of the producís from the mixture requires great precautions.

http://www.google.nl/patents/WO2004080958A2?cl=en

EXAMPLE 1 3-(Trifluoromethyl -5,6,7,8-tetrahydrori,2,41triazolor4.3-α1pyrazine, hydrochloride salt (1-4)

Step A: Preparation of bishydrazide (1-1)

H

Hydrazine (20.1 g, 35 wt% in water, 0.22 mol) was mixed with 310 mL of acetonitrile. 31.5 g of ethyl trifluoroacetate (0.22 mol) was added over 60 min. The internal temperature was increased to 25 °C from 14 °C. The resulting solution was aged at 22 - 25 °C for 60 min. The solution was cooled to 7 °C. 17.9 g of 50 wt% aqueous NaOH (0.22 mol) and 25.3 g of chloroacetyl chloride (0.22 mol) were added simultaneously over 130 min at a temperature below 16 °C. When the reaction was complete, the mixture was vacuum distilled to remove water and ethanol at 27 ~ 30 °C and under 26 ~ 27 in Hg vacuum. During the distillation, 720 mL of acetonitrile was added slowly to maintain constant volume (approximately 500 mL). The slurry was filtered to remove sodium chloride. The cake was rinsed with about 100 mL of acetonitrile. Removal of the solvent afforded bis-hydrazide \Λ

(43.2 g, 96.5% yield, 94.4 area% pure by HPLC assay).

1H-NMR (400 MHz, DMSO-dfc): δ 4.2 (s, 2H), 10.7 (s, 1H), and 11.6 (s, 1H) ppm.

13C-NMR (125 MHz, DMSO-_f6): δ 41.0, 116.1 (q, J = 362 Hz), 155.8 (q, J = 50 Hz), and 165.4 ppm.

HPLC conditions: Symmetry 4.6 x 250 mm C18 column; UV detection at 210 nm; mobile phase: 1:1 ACN: H₂O (0.1% H₃PO ); flow rate: 1 rnL/min; retention time of

1-1: 2.9 min.

Step B: Preparation of 5-(trifluoromethyl)-2-(chloromethyl)- 1.3 ,4-oxadiazole

F₃C

Bishydrazide LI from Step A (43.2 g, 0.21 mol) in ACN (82 mL) was cooled to

5 °C. Phosphorus oxychloride (32.2 g, 0.21 mol) was added, maintaining the temperature below 10 °C. The mixture was heated to 80 °C and aged at this temperature for 24 h until HPLC showed less than 2 area% of LI. In a separate vessel, 260 mL of LPAc and 250 mL of water were mixed and cooled to 0 °C. The reaction slurry was charged to the quench keeping the internal temperature below 10 °C. After the addition, the mixture was agitated vigorously for 30 min, the temperature was increased to room temperature and the aqueous layer was cut. The organic layer was then washed with 215 mL of water, 215 mL of 5 wt% aqueous sodium bicarbonate and finally 215 mL of 20 wt% aqueous brine solution. HPLC assay yield after work up was 86-92%. Volatiles were removed by distillation at 75-80 mm Hg, 55 °C to afford an oil which could be used directly in Step C without further purification. Otherwise the product can be purified by distillation to afford L2 in 70-80% yield. 1H-NMR (400 MHz, CDC1₃): 04.8 (s, 2H) ppm.

13C-NMR (125 MHz, CDC1₃): δ 32.1, 115.8 (q, J = 337 Hz), 156.2 (q, J = 50 Hz), and 164.4 ppm. HPLC conditions: Symmetry 4.6 x 250 mm C18 column; UV detection at 210 nm; mobile phase: 1:1 ACN: H₂O (0.1% H₃PO₄); flow rate: 1 rnL/min; retention time of 1-2: 8.8 min.

http://www.organic-chemistry.org/synthesis/heterocycles/1,3,4-oxadiazoles.shtm

Synthesis of 1,3,4-oxadiazoles

Recent Literature

A direct access to symmetrical and unsymmetrical 2,5-disubstituted [1,3,4]-oxadiazoles has been accomplished through an imine C-H functionalization of N-arylidenearoylhydrazide using a catalytic quantity of Cu(OTf)₂. These reactions can be performed in air atmosphere and moisture making it exceptionally practical for application in organic synthesis.
S. Guin, T. Ghosh, S. K. Rout, A. Banerjee, B. K. Patel, Org. Lett., 2011, 13, 5976-5979.

A facile and general protocol for the preparation of 2-amino-1,3,4-oxadiazoles relies on a tosyl chloride/pyridine-mediated cyclization of thiosemicarbazides that consistently outperforms the analogous semicarbazide cyclizations. Various 5-alkyl- and 5-aryl-2-amino-1,3,4-oxadiazoles have been prepared in good yields.
S. J. Dolman, F. Gosselin, P. D. O'Shea, I. W. Davies, J. Org. Chem., 2006, 71, 9548-9551.

An oxidative desulfurization approach enables the construction of oxadiazole and thiadiazole heterocycles in the presence of iodobenzene and Oxone. The use of iodobenzene and the inexpensive readily available oxidant Oxone makes the reaction system simple and versatile for desulfurization.
K. N. Patel, N. C. Jadhav, P. B. Jagadhane, V. N. Telvekar, Synlett, 2012, 23, 1970-1972.

The reaction of a thiosemicarbazide intermediate with EDC·HCl in DMSO or p-TsCl, triethylamine in N-methyl-2-pyrrolidone gives the corresponding 2-amino-1,3,4-oxadiazoles and 2-amino-1,3,4-thiadiazoles through regioselcective cyclization processes.
S.-J. Yang, S.-H. Lee, H.-J. Kwak, Y.-D. Gong, J. Org. Chem., 2013, 78, 438-444.

N-Isocyaniminotriphenylphosphorane, aldehydes, and benzoic acids undergo a one-pot, three-component reaction under mild conditions to afford 2-aryl-5-hydroxyalkyl-1,3,4-oxadiazoles in good yields.
M. Adib, M. R. Kesheh, S. Ansari, H. R. Bijanzadeh, Synlett, 2009, 1575-1578.

Symmetric and unsymmetric 1,3,4-oxadiazoles were synthesized in situ from hydrazine hydrate and the corresponding 2-acyl-4,5-dichloropyridazin-3-ones as acylating agents in polyphosphoric acid (PPA) or BF₃·OEt₂ in excellent yields.
Y.-D. Park, J.-J. Kim, H.-A. Chung, D.-H. Kweon, S.-D. Cho, S.-G. Lee, Y.-J. Yoon, Synthesis, 2003, 560-564.

A simple and straightforward method for the direct carboxylation of aromatic heterocylces such as oxazoles, thiazoles, and oxadiazoles using CO₂ as the C1 source requires no metal catalyst and only Cs₂CO₃ as the base. A good functional group tolerance is achieved.
O. Vechorkin, N. Hirt, X. Hu, Org. Lett., 2010, 12, 3567-3569.

http://www.google.com/patents/WO2002064135A1?cl=en

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THANKS AND REGARD’S
DR ANTHONY MELVIN CRASTO Ph.D

amcrasto@gmail.com

MOBILE-+91 9323115463

GLENMARK SCIENTIST ,  INDIA
web link

ABOUTME, BRAND ANTHONYCRASTO, COLLECTION OF SITE LINKS,BRAVESITES, GRAVATAR, JIMDO, SKILLPAGES, MIXXT, APNACIRCLE, ZIC ZAC, ZING ME, SCOOP IT, scribd, Stumbleupon, Delicious, pinnterest, tumblr, Newsvine, SLIDESHARE, ACADEMIA.EDU, GOOGLE PLUS, FACEBOOK, TWITTER, ISSUU, DIIGO,YOLASITE, Authorstream, Symbaloo, ISSUU, BLOGLOVIN, FRIENDFEED,NEWSVINE

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アンソニー     安东尼   Энтони    안토니     أنتوني

blogs are 

New Drug Approvals, ALL ABOUT DRUGS, WORLD DRUG TRACKER

MEDICINAL CHEM INTERNATIONAL, DRUG SYN INTERNATIONAL

SCALEUP OF DRUGS, ALL FOR DRUGS ON WEB,

• Green Chemistry International,  
• Eurekamoments in Organic Chemistry ,   
• WIX CHEMISTRY BLOG , 
• Drug regulatory affairs international 
• ORGANIC CHEMISTRY SELECT
• ORGANIC SPECTROSCOPY INTERNATIONAL 
• ORGANIC SYNTHESIS INTERNATIONAL 
• ORGANIC CHEMISTRY INTERNATIONAL
• DR ANTHONY MELVIN CRASTO  OLD BLOG

 MY CHINA, VIETNAM  AND JAPAN BLOGS

http://amcrasto.blog.fc2.com/

http://blog.sina.com.cn/u/5030268874

http://ameblo.jp/medchem-amcrasto/

http://me.zing.vn/u/amcrasto

ICELAND, RUSSIA, ARAB

BOBRDOBR, BLAND ICELAND, 100zakladok, adfty

GROUPS

you can post articles and will be administered by me on the google group which is very popular across the world

OPD GROUPSPACES, SCOOP OCI, organic-process-development GOOGLE, TVINX, MENDELEY WDT, SCIPEOPLE OPD,EPERNICUS OPD, SYNTHETIC ORGANIC CHEMISTRYLinkedIn group, DIIGO OPD, LINKEDIN OPD, WDT LINKEDIN, WDTI ZING

WORLD DRUG TRACKER FACEBOOK

DR ANTHONY MELVIN CRASTO Ph.D , 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 GLENMARK- GENERICS LTD, Research centre as 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 Sanofi Aventis,  & Searle India ltd, now Rpg lifesciences, etc. He has worked in Basic research, Neutraceuticals, Natural products, Flavors, Fragrances, Pheromones, Vet Drugs, Drugs, formulation, GMP etc. He has total 25 yrs exp in this field, 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 ,   WIX BLOG , WORLD DRUG TRACKER

• drug regulatory affairs international
• ORGANIC SPECTROSCOPY INTERNATIONAL
• ORGANIC SYNTHESIS INTERNATIONAL
• ALL ABOUT DRUGS
• ORGANIC CHEMISTRY INTERNATIONAL

are some most read chemistry blogs, He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 25 year tenure, good knowledge of IPM, GMP, Regulatory aspects, he has  several international drug patents published worldwide .

He has good proficiency in Technology Transfer, Spectroscopy ,Stereochemistry , Synthesis, Reactions in Org Chem , Polymorphism, Pharmaceuticals , Medicinal chemistry , Organic chemistry literature ,Patent related site , Green chemistry , Reagents , R & D , Molecules ,Heterocyclic chem , Sourcing   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