Nitrogen‐, and/or Sulfur-Containing Heterocyclic Rings Poulomi Majumdar,†,‡ Anita Pati,†,§ Manabendra Patra, Rajani Kanta Behera,† and Ajaya Kumar Behera*,† †Organic Synthesis Laboratory, School of Chemistry, Sambalpur University, Jyoti Vihar, Burla 768019, Orissa, India ‡State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, P.R. China School of Applied Sciences (Chemistry), KIIT University, Bhubaneswar 751024, India National Institute of Science & Technology, Palur Hill, Berhampur 761068, Orissa, India

Acid hydrazides, potent reagents for synthesis of oxygen-, nitrogen-, and/or sulfur-containing heterocyclic rings.

A large series of 3-carboxamido-7-substituted coumarins have been synthesized and tested in vitro for their human monoamine oxidase A and B (hMAO-A and hMAO-B) inhibitory activity. Taking into account all the relevant structural information on MAOs reported in the literature, we made some changes in the coumarin nucleus and examined with particular attention the effect on activity and selectivity of substituting at position 3 with N-aryl or N-alkyl carboxamide and at position 7 with a benzyloxy or a 4'-F-benzyloxy group. Some of the assayed compounds proved to be potent, selective inhibitors of hMAO-B with IC(50) values in the micromolar range. To better understand the enzyme-inhibitor interaction and to explain the selectivity of the most active compounds toward hMAOs, molecular modeling studies were carried out on new, high resolution, hMAO-A and hMAO-B crystallographic structures.

Synthesis, Molecular Modeling, and Selective Inhibitory Activity against Human Monoamine Oxidases of 3-Carboxamido-7-Substituted Coumarins†

Unsupported, high surface area MoP was synthesized by adding citric acid (CA) to solutions of ammonium heptamolybdate and diammonium hydrogen phosphate followed by drying (397 K), calcination (773–973 K), and reduction in H 2 (923 K). A tetrameric Mo citrate precursor was formed after drying which decomposed into a monomer of the form, Mo(C 4 H 5 O 3 CN)O 2 ·HPO 4 following calcination. Reduction of this monomer produced CH 4 , CO, CO 2 , NH 3 , H 2 O, and MoP. The C content of the reduced MoP-CA catalysts decreased from 12.8 to 4.0 wt% as the calcination temperature increased from 773 to 973 K, whereas the surface area decreased from 136 m 2 /g to 53 m 2 /g and the MoP particle size increased from 5 to 9 nm, respectively. The residual C acted as a structural promoter of the calcined samples, limiting agglomeration of the MoP crystallites during reduction so that nanoparticles (5–9 nm) of MoP were produced. The HDO of 4-methylphenol over the MoP-CA catalysts was found to be structure insensitive with an initial turnover frequency (TOF) of 0.079 s −1 at 623 K and 4.4 MPa H 2 . The ratio of hydrogenation to direct deoxygenation of 4-methylphenol (TOF HYD :TOF DDO  = 0.78:1) was independent of the MoP particle size and greater than that observed over MoS 2 .

The influence of citric acid on the synthesis and activity of high surface area MoP for the hydrodeoxygenation of 4-methylphenol

The biological and medicinal properties of 5-aminopyrazoles have prompted enormous research aimed at developing synthetic routes to these heterocyles. This review focuses on the biological properties associated with this system. Various synthetic methods developed up to 2010 for these compounds are described, particularly those that involve the reactions of β-ketonitriles, malononitrile, alkylidenemalononitriles and their derivatives with hydrazines, as well as some novel miscellaneous methods.

https://www.beilstein-journals.org/bjoc/content/pdf/1860-5397-7-25.pdf

Approaches towards the synthesis of 5-aminopyrazoles.

Heterocyclic antidepressants were the mainstay of antidepressant treatment fromtheir inception in the late 1950’s until the mid-1980’s. The development of synthetic he-terocyclic compounds as antidepressant, sedative or analgesic agents progressed consid-erably during the past decade (1–3). In recent years, the role of antidepressant drugs inthe management of different pain syndromes has elicited considerable interest (4, 5). Py-rimidine derivatives possessing anti-inflammatory, antidepressant and analgesic activi-ties have been reported in literature (6–8). Over the past few years, our research groupwas conducting a comprehensive program towards the synthesis of thiophenes andtheir fused derivatives (9–12). The importance of such compounds is based on their useas anti-flammatory (13, 14), anti-protozoal (15), and antitumor agents (16), templates for

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Screening for antidepressant, sedative and analgesic activities of novel fused thiophene derivatives

The reaction of cyanoacetylhydrazine with ω-bromoacetophenone gave the N-[2-bromo-1-phenylethylidene]-2-isocyanoacetohydrazide (3). The latter compound underwent ready cyclization when treated with potassium cyanide to give the 1-(isocyanoacetyl)-3-phenyl-1H-pyrazol-5-amine (6). Compound 6 underwent a series of heterocyclization to give either coumarin, pyridazine, 1,2,4-triazine or thiophene derivatives. The antimicrobial and antifungal activities of the newly synthesized products were measured, using two Gram-negative (Escherichia coli and Pseudomonas aeruginosa), two Gram-positive bacteria (Bacillus subtilis and Bacillus cereus) and the antifungal activity using Candida albicans

Synthesis of novel pyrazole, coumarin and pyridazine derivatives evaluated as potential antimicrobial and antifungal agents

This study was performed to investigate the reactivity of 5alpha-cholestan-3-one (1) towards various chemical reagents to produce new steroidal heterocyclic derivatives. The aminothieno[2, 3:2, 3]cholestane derivative 2 was synthesized according to Gewald's conditions. The diazonium salt of compound 2 coupled with malononitrile to afford dicyanomethylenhydrazinothieno[2', 3':2, 3]cholestane derivative 5. The behavior of compound 5 towards nitrogen nucleophiles and several active methylene reagents was investigated. Additionally, a variety of steroidal heterocyclic derivatives like compounds 15a, b-22a, b were synthesized starting with 5alpha-cholestan-3-one (1). The structures of the compounds were established based on the analytical and spectral data. The in vitro antimicrobial activity of some newly synthesized compounds against bacteria and fungi was studied.

Synthesis and Antimicrobial Evaluation of Some Novel Cholestane Heterocyclic Derivatives

The reaction of epi-androsterone with cyanoacetyl hydrazine (2) gave the hydrazone derivative3. The reactivity of3 towards chemical reagents was studied to give pyridine, thiazole and thiophene derivatives.

Sultamo-Steroid analogues, part VII: Synthesis of epi-androsterone derivatives with potential activity

The reaction of either Digitoxin or Digoxin with cyanoacetic acid hydrazide gave the hydrazone derivatives3a and3b respectively. The reactivity of the latter products towards chemical reagents was studied to give heterocyclic derivatives with potential biological activities.

The reaction of digitoxin and digoxin with cyanoacetic acid hydrazide: synthesis of coumarin, thiazole, thiophene and pyridine derivatives with potential biological activities.

Tryptophan methyl ester 2 reacts with ethyl cyanoacetate to form acetonitrilocarbonyltryptophan methylester 3. The latter reacts with cyanomethylene reagents, hydrazines, cyanomethylenes and sulfur to form the corresponding α-pyrido-3-indolopropanoate derivatives 6a,b, pyrazolyltryptophan methyl ester derivatives 8a,b and thiophenotryptophan methyl ester derivatives 10a,b, respectively. Also compound 3 reacts with benzaldehyde to give the condensated product 12. The reactivity of the latter product towards chemical reagents was studied to form pyridine, pyrazole and isoxazole derivatives.

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Nadia A. Louca

Papers

Synthesis of novel pyrazole, coumarin and pyridazine derivatives evaluated as potential antimicrobial and antifungal agents

Synthesis and Antimicrobial Evaluation of Some Novel Cholestane Heterocyclic Derivatives

Sultamo-Steroid analogues, part VII: Synthesis of epi-androsterone derivatives with potential activity

The reaction of digitoxin and digoxin with cyanoacetic acid hydrazide: synthesis of coumarin, thiazole, thiophene and pyridine derivatives with potential biological activities.

Synthesis of novel tryptophan derivatives of potential biological activity