Results 11 to 20 of about 38,574 (278)
Enantioselective Addition of Pyrazoles to Dienes** [PDF]
Angewandte Chemie International Edition, 2021 AbstractWe report the first enantioselective addition of pyrazoles to 1,3‐dienes. Secondary and tertiary allylic pyrazoles can be generated with excellent regioselectivity. Mechanistic studies support a pathway distinct from previous hydroaminations: a Pd0‐catalyzed ligand‐to‐ligand hydrogen transfer (LLHT).
Alexander Y. Jiu +4 more
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The Role of Flow Chemistry on the Synthesis of Pyrazoles, Pyrazolines and Pyrazole-Fused Scaffolds. [PDF]
MoleculesNitrogen-containing heterocycles are fundamental scaffolds in organic chemistry, particularly due to their prevalence in pharmaceuticals, agrochemicals and materials science. Among them, five-membered rings, containing two nitrogen atoms in adjacent positions—such as pyrazoles, pyrazolines and indazoles—are especially significant due to their versatile
Correia CM, Silva AMS, Silva VLM.
europepmc +4 more sources
Carbamidine-substituted Pyrazoles [PDF]
Nature, 1951 THE ease with which 1-substituted pyrazoles may be converted into the free imino compounds varies with the nature of the 1-substituent and the reacting substance. Thus, 1,3,5-trimethyl pyrazole may be nitrated1 and 1-phenyl pyrazole reduced to the pyrazoline2 without loss of the N-methyl or N-phenyl groups respectively.
J. Reilly, C. M. B. Murphy, F. L. Scott
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New Series of Pyrazoles and Imidazo-Pyrazoles Targeting Different Cancer and Inflammation Pathways [PDF]
Molecules, 2021 (1) Background: different previously synthesized pyrazoles and imidazo-pyrazoles showed interesting anti-angiogenic action, being able to interfere with ERK1/2, AKT and p38MAPK phosphorylation in different manners and with different potency; (2) Methods: here, a new small compound library, endowed with the same differently decorated chemical scaffolds,
Signorello M. G. +5 more
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Chalcones as versatile synthons for the synthesis of 5- and 6-membered nitrogen heterocylces [PDF]
, 2014 Chalcones belong to the flavonoid family which constitutes one of the major classes of naturally occurring oxygen heterocyclic compounds. The alpha,beta-unsaturated carbonyl system of chalcones possesses two electrophilic reactive centers allowing them ...
Albuquerque, Hélio +3 more
core +1 more source
Calixarene alpha-ketoacetylenes: versatile platforms for reaction with hydrazine nucleophile [PDF]
, 2018 Late stage diversification of calix[4]arenes and thiacalix[4]arenes with heterocycles remains a significant synthetic challenge and hampers further exploitation of the scaffolds.
Acharya +47 more
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Synthesis of 4-amino-3,5-dicyano-arylpyrazoles : part 2 : isolation and characterization of by-products [PDF]
, 2012 Reaction of (dicyanomethylidene-hydrazino)benzoic acids with chloroacetonitrile, under basic conditions, gave cyanomethyl-3-(7-amino-3,5-dicyano-1H-pyrazolo[4,3-d]pyrimidin-1-yl-benzoates and para substituted cyanomethyl benzoates, in addition to the ...
Campos, Ana M. F. Oliveira +3 more
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Synthesis of pyrazole and pyrazole amidocobaloximes
, 2004 Department of Chemistry, Osmania University, Hyderabad-500 007, India E-mail : ssnsirasani @yahoo.com Manuscript received 23 September 2002, revised 23 April 2003. accepted 11 July 2003 A series of cyano (ligand) cobaloximes have been prepared where, the ligand is pyrazole (Pz), 1-(acetamido)pyrazole (Apz), 1-(N-methylacetamido)pyrazole (MAPz), 1 ...
A. Rajeshwar Rao +3 more
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