• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4366-4370
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• 2011

A simple, green and cost-effective protocol was used for the aromatization of 1,3,5-trisubstituted-2-pyrazolines to the corresponding pyrazoles by in situ generation of iodine ($I^+$) from $H_2O_2$/AcOH or SSA or oxalic acid /KI or NaI system under thermal condition with moderate to good yields.

• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.23-24
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• 2004

• Archives of Pharmacal Research
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• v.13 no.2
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• pp.142-146
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• 1990

Reaction of ethyl 4-chloro-2-phenylpyrimidine-4-carboxylate (4) with 5-chloro-2-methylthiophenol or 3-aryl-4-phenyl-1, 2, 4-triazole-5 thiol yielded the corresponding thioethers (5) and (8a, b), respectively. Careful alkaline hydrolysis of (5) yielded the corresponding carboxylic acid (6). Reaction of (4) with p-aminoacetophenone yielded compound (10) which was reacted with certain aromatic aldehyde to afford the$\alpha,\beta$-unsaturated ketones (11a-d). Condensation of (11a-d) with malononitrile or phenylhydrazine yielded the 2-amino-3-cyanopyridines (12a-f) or the 2-pyrazolines (13a, b) respectively. Seven representative compounds were tested for their in vitro antimicrobial activity against some pathogenic micro-organisms, some of them were proved to be active.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.49-56
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• 2014

Different pyrazoline derivatives (6a-h and 7a-h) were synthesized by cyclization of substituted chalcones with hydrazine hydrate in acidic as well as basic conditions. Both the reactions were performed under conventional heating and microwave irradiation and percentage yields were compared. All the reactions were accelerated in acidic and basic conditions under microwave irradiation, with higher yields. All the synthesized compounds were characterized by their spectral study (IR, MS, $^1H$ and $^{13}C$ NMR) and were tested for their antibacterial and antifungal activity. The compounds 6g and 7g exhibited significant activity against S. aureu, 7g against E. faecalis, 6b and 7b against E. coli and 6b, 6c, 7b, 7c against S. typhi. The compounds 6d and 7d exhibited significant activity against C. albicans and 6c against M. luteus. Rest of the synthesized compounds showed moderate to poor activity against tested species with compared to standard.

• Bulletin of the Korean Chemical Society
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• v.33 no.6
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• pp.2012-2016
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• 2012

A convenient synthetic route has been developed to synthesize 5-(4-((2-phenylthiazol-4-yl) methoxy)phenyl)-3-(4-sustituted phenyl)pyrazolines (5a-f) and 5-(4-((2-phenylthiazol-4-yl)methoxy)phenyl)-3-(4-substituted phenyl)isoxazolines (6a-f) starting from 2-phenyl-4-chloromethylthiazole (1). The chloromethylthiazole (1) was first condensed with 4-hydroxy benzaldehyde (2) for obtaining 4-((2-phenylthiazol-4-yl)methoxy)benzaldehyde (3). Claisen-Smidth condensation of 4-((2-phenylthiazol-4-yl)methoxy)benzaldehyde (3) and acetophenones has been carried in alkaline alcohol and obtained 3-(4-((2-phenylthiazol-4-yl)methoxy)phenyl)-1-(4-substituted phenyl)prop-2-en-1-ones (4a-f). The cyclocondensation of 2-propen-1-ones has been first time carried separately with hydrazine hydrate and hydroxylamine hydrochloride in aqueous micellar tetradecyltrimethylammonium bromide (TTAB) medium for getting the titled heterocycles with good to excellent yields.

• Journal of the Korean Chemical Society
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• v.67 no.4
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• pp.306-310
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• 2023

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.953-954
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• 2004

• Journal of the Korean Chemical Society
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• v.61 no.5
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• pp.291-295
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• 2017

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1692-1696
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• 2014

A practical and efficient one-pot synthesis of 1,3,5-trisubstituted pyrazoles from ${\alpha},{\beta}$-enones and arylhydrazine hydrochlorides has been developed. The pyrazoles were formed via a tandem formation of the corresponding pyrazolines and an acid-catalyzed aerobic oxidation process.

• Archives of Pharmacal Research
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• v.15 no.4
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• pp.292-297
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• 1992

Coupling of naphthacylpyridinium bromide 2 [1-(2-naphthyl) ethanone-2-pyridinium bromide] with N-nitrosoacetarylamides afforded C-(2-naphthoyl)-N-arylmethanohydrazonoylpyridinium bromides 3A-C. Treatment of 3A-C with base afforded the corresponding tetrazines 6A-C. Cycloaddition of nitrilimines 5A-C to N-arylmaleimides, acrylonitrile, ethyl acrylate, acrylamide, fumaronitrile, $\alpha$-cyanocinnamonitriles, ethyl $\alpha$-cyano-p-nitrocinnamates and $\alpha$-cyano-p-nitrocinnamamide afforded the corresponding cycloadducts 7-14, respectively. The cycloadducts 11-14 undergo a facile thermal elimination of hydrogen cyanide to give the corresponding pyrazoles 18-21 respectively.