Enzymatic resolution of antidepressant drug precursors in an undergraduate laboratory

EducaçãoQuim. Nova 2015, 38(2), 285-287

Enzymatic resolution of antidepressant drug precursors in an undergraduate laboratory

Luís M. R. SolanoI; Nuno M. T. LourençoII,*

This paper describes a multi-step chemo-enzymatic synthesis of antidepressant drug precursors.


Publicado online: novembro 13, 2014
Quim. Nova, Vol. 38, No. 2, 285-287, 2015
*e-mail: nmtl@tecnico.ulisboa.pt
Luís M. R. Solanoa and Nuno M. T. Lourençob,* a Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal b Departamento de Bioengenharia, Instituto de Biotecnologia e Bioengenharia, Instituto Superior Técnico, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal
Recebido em 07/07/2014; aceito em 17/09/2014; publicado na web em 13/11/2014
The use of biocatalysts in synthetic chemistry is a conventional methodology for preparing enantiomerically enriched compounds. Despite this fact, the number of experiments in chemical teaching laboratories that demonstrate the potential of enzymes in synthetic organic chemistry is limited. We describe a laboratory experiment in which students synthesized a chiral secondary alcohol that can be used in the preparation of antidepressant drugs. This experiment was conducted by individual students as part of a Drug Synthesis course held at the Pharmacy Faculty, Lisbon University. This laboratory experiment requires six laboratory periods, each lasting four hours. During the first four laboratory periods, students synthesized and characterized a racemic ester using nuclear magnetic resonance spectroscopy and gas chromatography. During the last two laboratory periods, they performed enzymatic hydrolysis resolution of the racemic ester using Candida antarctica lipase B to yield enantiomerically enriched secondary alcohol. Students successfully prepared the racemic ester with a 70%-81% overall yield in three steps. The enzymatic hydrolysis afforded (R)- secondary alcohol with good enantioselectivity (90%–95%) and reasonable yields (10%–19%). In these experiments, students were exposed to theoretical and practical concepts of aromatic acylation, ketone reduction, esterification, and enzymatic hydrolysis. Keywords: sec-alcohols; esters; lípase; enantiomers; resolution.

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A rant about data quality: machines first, humans second…

Cheminformatics 2.0

GraphicalAbstractRecently one of my papers emerged through the publication system of Journal of Cheminformatics, entitled “Machines first, humans second: on the importance of algorithmic interpretation of open chemistry data“, co-authored with Antony Williams and Sean Ekins, and incorporated into the JC Bradley Memorial Issue. Spoiler alert: the paper is about how if you’re publishing open lab notebook data without adhering to rigorously defined standards for machine readability, then you’re mostly wasting your time, and arguably making the open data situation even worse than it already is. The tone of the article is a bit less polite than I normally try to be, so fair warning, but it’s all for a good cause.

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How to leave a strong impression

Org Prep Daily

I got a summer internship in a natural product synthetic group, a quarter century ago when I was in high school. It was a very nice lab, doing medicinal chemistry on cardioglycosides, and I really liked it there. But I didn’t realize that the PI from the group wasn’t thrilled to have me (he was asked to take some random kid as a community outreach initiative, and he could not turn it down.) So, I was promptly sent out of the way, to the library. In those days, the literature search used to be done with printed indexes of Chemical Abstracts. It was like slogging away through a supermarket shelf filled with phone books;  I spent three weeks doing this.

Undeterred, I was nagging the PI to have me try experimental chemistry. Finally, he would let me prepare an acetylated analog of a frog cardanolide, as analytical standard. He instructed…

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Retosiban, GSK221149A

New Drug Approvals

Retosiban structure.svg

Retosiban, GSK221149A


MW 494.5827, MF C27 H34 N4 O5

Oxytocin antagonist

Threatened pre-term labour


UNII-GIE06H28OX, GSK 221149A,  820957-38-8,



(3R.6R)-3-(2,3-dihvdro-1 H-inden-2-v0-1 -( R)-1 -(2-methyl-1 ,3-oxazol-4- yl)-2-(4-morpholinyl)-2-oxoethyll-6-r(1S -1-methylpropyn-2.5- piperazinedione

2,​5-​Piperazinedione, 3-​(2,​3-​dihydro-​1H-​inden-​2-​yl)​-​1-​[(1R)​-​1-​(2-​methyl-​4-​oxazolyl)​-​2-​(4-​morpholinyl)​-​2-​oxoethyl]​-​6-​[(1S)​-​1-​methylpropyl]​-​, (3R,​6R)​-

Morpholine, 4-[(2R)-[(3R,6R)-3-(2,3-dihydro-1H-inden-2-yl)-6-[(1S)-1-methylpropyl]-2,5-dioxo-1-piperazinyl](2-methyl-4-oxazolyl)acetyl]-

Retosiban (GSK-221,149-A)[1][2] is an oral drug which acts as a selective, sub-nanomolar (Ki = 0.65 nM) oxytocin receptorantagonist with >1400-fold selectivity[3] over the related vasopressin receptors and is being developed by GlaxoSmithKline for the treatment of preterm labour.[4][5]

Retosibanis an oxytocin (OT) antagonist in phase III clinical trials at GlaxoSmithKline for the prevention of preterm labor. OT antagonism is widely known to inhibit spontaneous uterine contractions.

Retosiban is a diketopiperazine nonpeptide compound with high potency and selectivity for the OT receptor over vasopressin receptors.

This  candidate has been shown to block oxytocin-induced…

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XMDS: progress toward structure sketcher

Cheminformatics 2.0

xmds_sk01Since the last sneak preview, the skunkworks project “XMDS” – the Mac OS X desktop version of the Mobile Molecular DataSheet app – has gained enough functionality to make another screenshot, this time showing what the actual molecular drawing interface might look like once it’s done.

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New Drug Approvals



Molecular Formula: C18H20FN3O4; (Formula Weight: 361.37;

mp: 270-275°C;

Ofloxacin is one kind of white or almost powder or off-white solid.

The Systematic (IUPAC) name of this chemical is (RS)-7-fluoro-2-methyl-6-(4-methylpiperazin-1-yl)-10-oxo-4-oxa-1-azatricyclo[,13]trideca-5(13),6,8,11-tetraene-11-carboxylic acid


Apazix; Bactocin; Exocin; Flobacin; Floxal; Floxil; Floxin; Girasid; Monoflocet; Ocuflox; Oflocet; Oflocin; Oxaldin; Tarivid; Urosin; Visiren; Zanocin

DL-8280; HOE-280; Ofloxacinum


OFLOXACIN was developed as a broader-spectrum analog of norfloxacin, the first fluoroquinolone antibiotic, Ofloxacin was first patented in 1982 (European Patent Daiichi) and received U.S. Food and Drug Administration (FDA) approval December 28, 1990. In the United States name branded ofloxacin is rarely used anymore, having been discontinued by the manufacturer (Ortho McNeil Janssen). Johnson and Johnson’s annual sales of Floxin in 2003 was approximately $30 million, where as their combined sales of Levaquin/Floxin exceeded $ 1.15 billion in the same year. During the 2008 Johnson & Johnson shareholder’s meetings, the…

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CS 3150, angiotensin II receptor antagonist, for the treatment or prevention of such hypertension and heart disease

New Drug Approvals

CS-3150,  (XL550)

CS 3150, angiotensin II receptor antagonist,  for the treatment or prevention of such hypertension and heart disease similar to olmesartan , losartan, candesartan , valsartan,  irbesartan,  telmisartan, eprosartan,

 Cas name 1H-​Pyrrole-​3-​carboxamide, 1-​(2-​hydroxyethyl)​-​4-​methyl-​N-​[4-​(methylsulfonyl)​phenyl]​-​5-​[2-​(trifluoromethyl)​phenyl]​-​, (5S)​-

CAS 1632006-28-0 for S conf

MF C22 H21 F3 N2 O4 S

MW 466.47


CAS 1632006-28-0 for S configuration

1- (2-hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide

(S) -1- (2- hydroxyethyl) -4-methyl -N- [4- (methylsulfonyl) phenyl] -5- [2- (trifluoromethyl) phenyl] -1H- pyrrole-3-carboxamide

(+/-)-1-(2-hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl)phenyl]-5-[2-(trifluoromethyl)phenyl]-1H-pyrrole-3-carboxamide, CAS 880780-76-7



WO 2014168103

WO 2008126831

WO2008 / 126831 (US Publication US2010-0093826)http://www.google.co.in/patents/EP2133330A1?cl=en

WO 2015012205

WO 2006012642..compound A;..http://www.google.com/patents/WO2006012642A2?cl=en

WO2006 / 012642 (US Publication US2008-0234270)

WO 2015030010…http://www.google.com/patents/WO2015030010A1?cl=en

JAPAN PHASE 2……….Phase 2…

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7-allyl-6-hydroxy-indan-1-one…Mom will teach you NMR

Figure US08242291-20120814-C00009

Thermal Claisen rearrangement on 6-allyloxy-indan-1-one,  (III) to obtain 7-allyl-6-hydroxy-indan-1-one, (IV):

  • Formula: C12H12O2
  • Molecular Weight: 188.22200


This example refers to reaction b of the process of the invention.
20 kg of the intermediate of formula (III) prepared as described in example 1 are suspended in 50 l of Dowtherm A under nitrogen flow. In an inert atmosphere, it is heated to approximately 200° C. for approximately 5 hours. Upon completion of the reaction (TLC) a clear red-brown solution is obtained, without the formation of black pitch. The reaction mixture is cooled slowly to 25° C. (a partial precipitation is observed). 100 l (5 volumes) of cyclohexane are added and it is cooled to between 0 and 5° C. for one hour. It is filtered by washing with cyclohexane and dried at reduced pressure and T=45° C. for at least 12 hours. 16.8 kg of yellow solid are obtained which is refluxed in 80 l of toluene in the presence of decolouring carbon. The suspension is filtered, washing it with hot toluene. Part of the solvent is distilled at reduced pressure until the beginning of crystallisation. It is cooled at room temperature and then to between 0 and 5° C. for at least one hour.
The filtered solid is washed with cold toluene and dried at reduced pressure at T=45° C. for at least 12 hours. 15.3 kg of intermediate (IV) are obtained in the form of an almost white solid of quality suitable for continuation of the synthesis.
1H-NMR and mass spectroscopic analyses are performed on part of the product thus obtained, purified by chromatography for analytical purposes (silica gel, 7 parts in volume of heptane—3 parts in volume of ethyl acetate), obtaining the following results:
Electron impact mass: [M+]=188
1H-NMR (500 MHz, CDCl3): δ (ppm)
2.72 ppm, t, J=6 Hz, 2H,  AR C=OCH2 CH2 AR
3.03 ppm, t, J=6 Hz, 2H, AR C=OCH2 CH2 AR
4.03 ppm, d, J=6 Hz, 2H, ARCH2CH=CH2
5.13-5.20, Σd, 2H, ARCH2CH=CH2
5.60 ppm, s, 1H, 0H
5.98-6.10 ppm, m, 1H, CH2CH=CH2
7.13 ppm, d, J=8 Hz, 1H, AR
7.25, d, J=8 Hz, 1H. AR

6-hydroxy-7-prop-2-enyl-2,3-dihydroinden-1-one NMR spectra analysis, Chemical CAS NO. 320574-77-4 NMR spectral analysis, 6-hydroxy-7-prop-2-enyl-2,3-dihydroinden-1-one H-NMR spectrum13 C NMR


6-hydroxy-7-prop-2-enyl-2,3-dihydroinden-1-one NMR spectra analysis, Chemical CAS NO. 320574-77-4 NMR spectral analysis, 6-hydroxy-7-prop-2-enyl-2,3-dihydroinden-1-one C-NMR spectrum




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DR ANTHONY MELVIN CRASTO Ph.D ( ICT, Mumbai) , INDIA 25Yrs Exp. in the feld of Organic Chemistry,Working for GLENMARK GENERICS at Navi Mumbai, INDIA. Serving chemists around the world. Helping them with websites on Chemistry.Million hits on google, NO ADVERTISEMENTS , ACADEMIC , NON COMMERCIAL SITE, world acclamation from industry, academia, drug authorities for websites, blogs and educational contribution, ……..amcrasto@gmail.com……….+91 9323115463