A series of 1-phenyl-3-aryl-5-(4-(2-ethanoloxy) phenyl)-1H-pyrazoles were synthesized from chalcones and studied for their in vitro antibacterial activity. Chalcones i.e.,1-aryl-3-(4hydroxyphenyl) prop-2-en-1-ones, 1 on reaction with phenyl hydrazine yielded the corresponding 1-phenyl-3-aryl-5-(4-hydroxyphenyl)-1H-pyrazoles 2 which on further reaction with 3-chloroethanol furnished the title co...

Enaminone 1 was reacted with hydrazonoyl halides 2a-d to yield 3,4-disubstituted pyrazoles 6a-d. Coupling with arenediazonium chlorides afforded the 2-(arylhydrazono)-3-(1-naphthalenyl)-3-oxopropionaldehydes 13a-c. Compounds 13 could be utilized for the synthesis of a variety of arylpyrazoles, arylazolopyrimidines, and pyridazinones via reaction with hydrazines, aminoazoles, and active methylen...

5-Amino-N-aryl-3-[(4-methoxyphenyl)amino]-1H-pyrazole-4-carboxamides 4a-c were synthesized by the reaction of N-(aryl)-2-cyano-3-[(4-methoxyphenyl)amino]-3-(methylthio)acrylamides 3a-c with hydrazine hydrate in ethanol. The reaction of 5-amino-N-aryl-1H-pyrazoles 4a-c with acetylacetone 5 or 2-(4-methoxybenzylidene)malononitrile 8 yielded the pyrazolo[1,5-a]pyrimidine derivatives 7a-c and 10a-c...

2-(6,8-Dibromo-2-methylquinazolin-4-yloxy)-acetohydrazide (4) was prepared by the reaction of 6,8-dibromo-2-methylbenzo-[d][1,3]oxazin-4-one with formamide to afford quinazolinone 2, followed by alkylation with ethyl chloroacetate to give the ester 3. Treatment of ester 3 with hydrazine hydrate and benzaldehyde afforded 4 and styryl quinazoline 5. The hydrazide was reacted with triethyl orthofo...

To develop compounds that are antagonists on ER , but not ER , we have added basic side-chains typically found in nonsteroidal antiestrogens to pyrazole compounds that bind with much higher affinity to ER than to ER . In this way we have developed basic side-chain pyrazoles (BSC-pyrazoles) that are high affinity, potent, selective antagonists on ER . These BSCpyrazoles are themselves inactive o...

A simple, efficient, and environmentally friendly protocol for the synthesis of 1,3,5-triarylpyrazole in [bimm][PF6] ionic liquid mediated by Cu(OTf)2 is described. The reaction protocol gave 1,3,5-triarylpyrazoles in good to high yields (71-82%) via a one-pot addition–cyclocondensation between hydrazines and chalcones, and oxidative aromatization without requirement for an additional oxidizing...

C3-arylated indazole and pyrazoles are privileged structural motifs in agrochemicals and pharmaceuticals. C-3 C-H arylation of (1H) indazole and pyrazole has been a significant challenge due to the poor reactivity of the C-3 position. Herein, we report a practical Pd(II)/Phen catalyst and conditions for direct C-3 arylation of indazole and pyrazole with ArI or ArBr without using Ag additives as...

Decomposition of donor-acceptor diazo compounds leads to the formation reactive carbene intermediates. These can undergo a wide variety transfer reactions yield synthetically useful products. Herein, we report selective borane catalyzed cyclization reaction from combination two different afford N-substituted pyrazoles. The decomposition more α-aryl α-diazoester and subsequent with vinyl diazoac...

Pyrazoles have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The incorporation of the essential structural features of pyrazoles with a ferrocene moiety could provide new derivatives with unexpected and/or enhanced biological activities since several ferr...

An efficient method for the synthesis of 3,5-disubstituted pyrazoles is described. The reactions of 1,3-dialkynes with hydrazine proceeded smoothly in dimethyl sulfoxide under mild reaction conditions to produce 3,5-disubstituted pyrazoles in satisfactory to excellent yields. A one-pot procedure of the transformation has been developed.