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DR ANTHONY MELVIN CRASTO, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his Ph.D from ICT, 1991,Matunga, Mumbai, India, in Organic Chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with GLENMARK PHARMACEUTICALS LTD, Research Centre as Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Total Industry exp 30 plus yrs, Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri, Dr T.V. Radhakrishnan and Dr B. K. Kulkarni, etc, He did custom synthesis for major multinationals in his career like BASF, Novartis, Sanofi, etc., He has worked in Discovery, Natural products, Bulk drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, etc, he is now helping millions, has 9 million plus hits on Google on all Organic chemistry websites. His friends call him Open superstar worlddrugtracker. His New Drug Approvals, Green Chemistry International, All about drugs, Eurekamoments, Organic spectroscopy international, etc 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 30 year tenure till date Dec 2017, Around 35 plus products in his career. He has good knowledge of IPM, GMP, Regulatory aspects, he has several International patents published worldwide . He has good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc., He suffered a paralytic stroke/ Acute Transverse mylitis in Dec 2007 and is 90 %Paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, He has 9 million plus hits on Google, 2.5 lakh plus connections on all networking sites, 50 Lakh plus views on dozen plus blogs, He makes himself available to all, contact him on +91 9323115463, email, Twitter, @amcrasto , He lives and will die for his family, 90% paralysis cannot kill his soul., Notably he has 19 lakh plus views on New Drug Approvals Blog in 216 countries...... , He appreciates the help he gets from one and all, Friends, Family, Glenmark, Readers, Wellwishers, Doctors, Drug authorities, His Contacts, Physiotherapist, etc

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The synthesis, biological evaluation and structure–activity relationship of 2-phenylaminomethylene-cyclohexane-1,3-diones as specific anti-tuberculosis agents



CAS  74102-02-6

Molecular Formula: C15H17NO3
Molecular Weight: 259.305 g/mol

2-(((2-hydroxyphenyl)amino)methylene)-5,5-dimethylcyclohexane-1,3-dione (39): White solid; m.p. 249 o C; TLC Rf value, 0.48 (in EtOAc:Hexane,60:40);

IR (neat) 2980, 2950, 1678, 1040 cm-1;

1 H NMR (400 MHz, CD3OD) δ 9.86 (1H, bs), 8.66 (1H, d, J = 16.0 Hz), 7.46- 7.34 (1H, m), 7.07-6.84 (3H, m), 2.46 (2H, s), 2.41 (2H, s), 1.10 (3H, s), 1.09 (3H, s);

13C NMR (101 MHz, CDCl3) δ 199.8, 197.2, 149.6, 149.3, 147.8, 127.2, 126.6, 120.6, 120.3, 108.

The synthesis, biological evaluation and structure–activity relationship of 2-phenylaminomethylene-cyclohexane-1,3-diones as specific anti-tuberculosis agents

 Author affiliations


The present study utilised whole cell based phenotypic screening of thousands of diverse small molecules against Mycobacterium tuberculosis H37Rv (M. tuberculosis) and identified the cyclohexane-1,3-dione-based structures 5 and 6 as hits. The selected hit molecules were used for further synthesis and a library of 37 compounds under four families was synthesized for lead generation. Evaluation of the library against M. tuberculosis lead to the identification of three lead antituberculosis agents (3739 and 41). The most potential compound, 2-(((2-hydroxyphenyl)amino)methylene)-5,5-dimethylcyclohexane-1,3-dione (39) showed an MIC of 2.5 μg mL−1, which falls in the range of MICs values found for the known antituberculosis drugs ethambutol, streptomycin and levofloxacin. Additionally, this compound proved to be non-toxic (<20% inhibition at 50 μM concentration) against four human cell lines. Like first line antituberculosis drugs (isoniazid, rifampicin and pyrazinamide) this compound lacks activity against general Gram positive and Gram negative bacteria and even against M. smegmatis; thereby reflecting its highly specific antituberculosis activity.

Graphical abstract: The synthesis, biological evaluation and structure–activity relationship of 2-phenylaminomethylene-cyclohexane-1,3-diones as specific anti-tuberculosis agents!divAbstract
Background Image

Muzafar Ahmad Rather

Ph.D Research Scholar

CSIR-Indian Institute of Integrative Medicine (CSIR-IIIM), Srinagar

Clinical Microbiology and PK/PD Division, Clinical Microbiology PK/PD/Laboratory, CSIR-Indian Institute of Integrative Medicine, Sanatnagar, Srinagar, India-190005

Image result for Zahoor Ahmad CSIR

CSIR-Indian Institute of Integrative Medicine

(Council of Scientific & Industrial Research)

Dr. Zahoor Ahmad Parry

Clinical Microbiology Division
CSIR – Indian Institute of Integrative Medicine,Canal Road, Jammu – 180001
Positions Held
Position Held Date Organization
Sr. Scientist   2010 – Present CSIR-IIIM

Dr. Bilal Ahmad Bhat

Medicinal Chemistry Division
CSIR – Indian Institute of Integrative Medicine,Canal Road, Jammu – 180001
Positions Held
Position Held Date Organization
Scientist 2010 – Present CSIR-IIIM

Image result for Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Sanatnagar, Srinagar,

Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Sanatnagar, Srinagar,

A small Drug Research Laboratory working under the Government of Jammu & Kashmir was taken over by CSIR in 1957 and named as Regional Research Laboratory, Jammu. Col. Sir Ram Nath Chopra, who is acclaimed the father of modern Pharmacology in India, was the Director of Drug Research Laboratory, continued as the first Director of Regional Research Laboratory. Having significant expertise in the area of medicinal & aromatic plants, Col. Chopra started its related R&D activities such as collection of plants from north & north-west and study the chemistry & pharmacology of the plant extracts and the new molecules isolated from these plants. Thus the initial mandate of this laboratory was mainly focused on screening the flora of north India for new molecules and to study the biological activity of these molecules. Gradually the activities of the institute increased, many more disciplines were introduced, that were important for the exploitation of regional resources such as mineral technology division, paper & pulp, fur technology division, sericulture, food technology division and mycology division. The main stream department such as chemistry, botany and pharmacology were strengthened by the introduction of a small animal house, instrumentation and chemical engineering & design division. The activity of the institute gradually increased which showed up in its publications and technology developments.

With the progress of time, the institute developed high quality expertise and infrastructure for working in the area of plant based products & drugs to explore new botanicals for new molecules and new activity. The institute specialized for working in the area of chemistry of natural products, synthesis of new & nature like molecules. These were studied for their use on various indication such as Oncology, hepatoprotection, anti-bacterial, bio-enhancers, anti-diabetes, anti-inflammation, aphrodisiac, hypertension, immunomodulation, anti-oxidants, oral care and beauty care. Some of the areas which did not progress to the satisfaction level gradually became redundant and were dropped.

Keeping in view the expertise developed in the area of natural products and revised mandate of the institute to explore and exploit natural, nature like and synthetic products with modern scientific tools to reduce the burden of disease, the institute became more focused towards integrative medicine hence was renamed as Indian Institute of Integrative Medicine in 2007 by the governing body of CSIR

////////////////// synthesis, biological evaluation, structure–activity relationship, 2-phenylaminomethylene-cyclohexane-1,3-diones, anti-tuberculosis agents




“NEW DRUG APPROVALS ” CATERS TO EDUCATION GLOBALLY, No commercial exploits are done or advertisements added by me. This is a compilation for educational purposes only. P.S. : The views expressed are my personal and in no-way suggest the views of the professional body or the company that I represent

The greening of peptide synthesis


The greening of peptide synthesis


The synthesis of peptides by amide bond formation between suitably protected amino acids is a fundamental part of the drug discovery process. However, the required coupling and deprotection reactions are routinely carried out in dichloromethane and DMF, both of which have serious toxicity concerns and generate waste solvent which constitutes the vast majority of the waste generated during peptide synthesis. In this work, propylene carbonate has been shown to be a green polar aprotic solvent which can be used to replace dichloromethane and DMF in both solution- and solid-phase peptide synthesis. Solution-phase chemistry was carried out with Boc/benzyl protecting groups to the tetrapeptide stage, no epimerisation occurred during these syntheses and chemical yields for both coupling and deprotection reactions in propylene carbonate were at least comparable to those obtained in conventional solvents. Solid-phase peptide synthesis was carried out using Fmoc protected amino acids on a ChemMatrix resin and was used to prepare the biologically relevant nonapeptide bradykinin with comparable purity to a sample prepared in DMF.

Graphical abstract: The greening of peptide synthesis
Boc-Ala-Phe-OBn 5a    ref S1
Boc-Ala-OH (324 mg, 1.71 mmol) and HCl.H-Phe-OBn (500 mg, 1.71 mmol) were coupled according to the general coupling procedure. The residue was purified using flash column chromatography (35:65, EtOAc:PE) to give Boc-Ala-Phe-OBn 5a as a white crystalline solid (682 mg, 93%). RF = 0.34 (40:60, EtOAc:PE);
mp 95.6-96.3 °C;
[α]D 23 -27.7 (c 1.0 in MeOH);
IR (Neat) νmax 3347 (m), 3063 (w), 3029 (w), 2928 (m), 2852 (w), 1735 (w), 1684 (w) 1666 (w) and 1521 (s) cm-1;
1H NMR (400 MHz, CDCl3): δ = 7.36-7.31 (m, 3H, ArH), 7.29-7.24 (m, 2H, ArH), 7.26-7.21 (m, 3H, ArH), 7.04-6.97 (m, 2H, ArH), 6.72 (d J 7.7 Hz, 1H, Phe-NH), 5.16-5.10 (m, 1H, Ala-NH), 5.13 (d J 12.1 Hz, 1H, OCH2Ph), 5.07 (d J 12.1 Hz, 1H, OCH2Ph), 4.88 (dt, J 7.7, 5.9 1H, PheNCH), 4.11 (br, 1H, Ala-NCH), 3.13 (dd J 13.9, 6.1 Hz, 1H, CH2Ph), 3.08 (dd J 13.9, 6.1 Hz, 1H, CH2Ph), 1.41 (s, 9H, C(CH3)3), 1.29 (d J 6.6 Hz, 3H, CH3);
13C NMR (100 MHz, CDCl3): δ = 172.3 (C=O), 171.2 (C=O), 155.6 (NC=O), 135.7 (ArC), 135.1 (ArC), 129.5 (ArCH), 128.7 (ArCH), 128.6 (ArCH), 127.2 (ArCH), 80.2 (CMe3), 67.4 (OCH2Ph), 53.3 (Phe-NCH), 50.3 (Ala-NCH), 38.0 (CH2Ph), 28.4 (C(CH3)3), 18.5 (CH3);
MS (ESI) m/z 449 [(M+Na)+ , 100]; HRMS (ESI) m/z calculated for C24H30N2O5Na 449.2048 (M+Na)+ , found 449.2047 (0.6 ppm error).
S1 J. Nam, D. Shin, Y. Rew and D. L. Boger, J. Am. Chem. Soc., 2007, 129, 8747–8755; Q. Wang, Y. Wang and M. Kurosu, Org. Lett., 2012, 14, 3372–3375.
General procedure for peptide coupling reactions in PC To a suspension of an N-Boc-amino acid (1.0 eq.) and an amino acid or peptide benzyl ester (1.0 eq.) in PC (5 mL mmol-1), at 0 °C, was added a solution of HOBt (1.1 eq.) and i Pr2EtN (3.0 eq.) in a minimal quantity of PC. EDC (1.1 eq.) was added dropwise and the reaction mixture was allowed to stir at room temperature for 16h. The reaction mixture was then diluted using EtOAc (50 mL) and washed with 1M HClaq (3 × 25 mL), saturated Na2CO3 (3 × 25 mL) and H2O (3 × 25 mL). The organic layer was dried (MgSO4 ), filtered and concentrated in vacuo. Any residual PC was removed via short path distillation. Purification details for each peptide and characterising data are given in the supplementary information. General procedure for Boc deprotections in PC An N-Boc-peptide benzyl ester (1.0 eq.) was dissolved in a minimum amount of PC and trifluoroacetic acid (60 eq.) was added. The reaction mixture was allowed to stir for 3h. at room temperature before being concentrated in vacuo. Any residual PC was removed via short path distillation. Characterising data for each deprotected peptide are given in the supplementary information.
Procedure for Boc deprotection of dipeptide 5a using HCl in PC Boc-Ala-Phe-OBn 5a (50 mg, 0.117 mmol) was dissolved in PC (2.34 mL). MeOH (0.40 mL, 9.8 mmol) was added and the solution cooled to 0 o C. Acetyl chloride (0.67 mL, 9.36 mmol) was added dropwise and the solution allowed to stir at room temperature for 2h. Then, PC was removed by short path distillation. The residue was suspended in Et2O and stirred for 5 minutes before being filtered to give HCl.Ala-Ph-OBn as a white solid (32.4 mg, 76%).
Propylene carbonate 1 has been shown to be a green replacement for reprotoxic amide based solvents which are widely used in peptide synthesis. Both solution- and solidphase peptide synthesis can be carried out in propylene carbonate using acid and base labile amine protecting groups respectively. No significant racemisation of the activated amino acids occurs in propylene carbonate and the viability of solid-phase peptide synthesis in propylene carbonate was demonstrated by the synthesis of the nonapeptide bradykinin.

Flow Chemistry: Recent Developments in the Synthesis of Pharmaceutical Products

Abstract Image

Recently, application of the flow technologies for the preparation of fine chemicals, such as natural products or Active Pharmaceutical Ingredients (APIs), has become very popular, especially in academia. Although pharma industry still relies on multipurpose batch or semibatch reactors, it is evident that interest is arising toward continuous flow manufacturing of organic molecules, including highly functionalized and chiral compounds. Continuous flow synthetic methodologies can also be easily combined to other enabling technologies, such as microwave irradiation, supported reagents or catalysts, photochemistry, inductive heating, electrochemistry, new solvent systems, 3D printing, or microreactor technology. This combination could allow the development of fully automated process with an increased efficiency and, in many cases, improved sustainability. It has been also demonstrated that a safer manufacturing of organic intermediates and APIs could be obtained under continuous flow conditions, where some synthetic steps that were not permitted for safety reasons can be performed with minimum risk. In this review we focused our attention only on very recent advances in the continuous flow multistep synthesis of organic molecules which found application as APIs, especially highlighting the contributions described in the literature from 2013 to 2015, including very recent examples not reported in any published review. Without claiming to be complete, we will give a general overview of different approaches, technologies, and synthetic strategies used so far, thus hoping to contribute to minimize the gap between academic research and pharmaceutical manufacturing. A general outlook about a quite young and relatively unexplored field of research, like stereoselective organocatalysis under flow conditions, will be also presented, and most significant examples will be described; our purpose is to illustrate all of the potentialities of continuous flow organocatalysis and offer a starting point to develop new methodologies for the synthesis of chiral drugs. Finally, some considerations on the perspectives and the possible, expected developments in the field are briefly discussed.

Two examples out of several in the publication discussed below……………

1  Diphenhydramine Hydrochloride

Scheme 1. Continuous Flow Synthesis of Diphenhydramine Hydrochloride
Diphenhydramine hydrochloride is the active pharmaceutical ingredient in several widely used medications (e.g., Benadryl, Zzzquil, Tylenol PM, Unisom), and its worldwide demand is higher than 100 tons/year.
In 2013, Jamison and co-workers developed a continuous flow process for the synthesis of 3minimizing waste and reducing purification steps and production time with respect to existing batch synthetic routes (Scheme 1). In the optimized process, chlorodiphenylmethane 1 and dimethylethanolamine 2 were mixed neat and pumped into a 720 μL PFA tube reactor (i.d. = 0.5 mm) at 175 °C with a residence time of 16 min. Running the reaction above the boiling point of 2and without any solvent resulted in high reaction rate. Product 3, obtained in the form of molten salt (i.e., above the melting point of the salt), could be easily transported in the flow system, a procedure not feasible on the same scale under batch conditions.
The reactor outcome was then combined with preheated NaOH 3 M to neutralize ammonium salts. After quenching, neutralized tertiary amine was extracted with hexanes into an inline membrane separator. The organic layer was then treated with HCl (5 M solution in iPrOH) in order to precipitate diphenhydramine hydrochloride 3 with an overall yield of 90% and an output of 2.4 g/h.

2 Olanzapine

Scheme 2. Continuous Flow Synthesis of Olanzapine
Atypical antipsychotic drugs differ from classical antipsychotics because of less side effects caused (e.g., involuntary tremors, body rigidity, and extrapyramidal effects). Among atypical ones, olanzapine 10, marketed with the name of Zyprexa, is used for the treatment of schizophrenia and bipolar disorders.
In 2013 Kirschning and co-workers developed the multistep continuous flow synthesis of olanzapine 10 using inductive heating (IH) as enabling technology to dramatically reduce reaction times and to increase process efficiency.(16) Inductive heating is a nonconventional heating technology based on the induction of an electromagnetic field (at medium or high frequency depending on nanoparticle sizes) to magnetic nanoparticles which result in a very rapid increase of temperature.As depicted in Scheme 2 the first synthetic step consisted of coupling aryl iodide 4 and aminothiazole 5 using Pd2dba3 as catalyst and Xantphos as ligand. Buchwald–Hartwig coupling took place inside a PEEK reactor filled with steel beads (0.8 mm) and heated inductively at 50 °C (15 kHz). AcOEt was chosen as solvent since it was compatible with following reaction steps. After quenching with distilled H2O and upon in-line extraction in a glass column, crude mixture was passed through a silica cartridge in order to remove Pd catalyst. Nitroaromatic compound 6 was then subjected to reduction with Et3SiH into a fixed bed reactor containing Pd/C at 40 °C. Aniline 7 was obtained in nearly quantitative yield, and the catalyst could be used for more than 250 h without loss of activity. The reactor outcome was then mixed with HCl (0.6 M methanol solution) and heated under high frequency (800 kHz) at 140 °C. Acid catalyzed cyclization afforded product 8 with an overall yield of 88%. Remarkably, the three step sequence did not require any solvent switch, and the total reactor volume is about 8 mL only.
The final substitution of compound 8 with piperazine 9 was carried out using a 3 mL of PEEK reactor containing MAGSILICA as inductive material and silica-supported Ti(OiPr)4 as Lewis acid. Heating inductively the reactor at 85 °C with a medium frequency (25 kHz) gave Olanzapine 10 in 83% yield.


Flow Chemistry: Recent Developments in the Synthesis of Pharmaceutical Products

Dipartimento di Chimica, Università degli Studi di Milano Via Golgi 19, I-20133 Milano, Italy
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.5b00325
Publication Date (Web): November 26, 2015
Copyright © 2015 American Chemical Society

ACS Editors’ Choice – This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.

Riccardo Porta

Riccardo Porta

 PhD Student
Dipartimento di Chimica, Università degli Studi di Milano Via Golgi 19, I-20133 Milano, Italy

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New Route to Anticancer Agent Quinocarcin

Compound Structure


Antibiotic DC 52, DC 52, CHEBI:554143, CID158486, LS-80981, 3,6-Imino-1H-2-oxa-11c-azanaphth(1,2,3-cd)azulene-5-carboxylic acid, 2a,3,4,5,6,6a,7,11b-octahydro-11-methoxy-12-methyl-, (2a-alpha,3-alpha,5-alpha,6-alpha,6a-alpha,11b-alpha)-, (-)-, 84573-33-1

Synthesis of quinocarcin through a convergent strategy based on Sonogashira coupling and gold(I)-catalyzed hydroamination

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