Results 51 to 60 of about 53,373 (308)

Photochemistry of 3H-furo[3,4-c]pyrazoles and 3H-thieno[3,4-c] pyrazoles

, 2013
The first examples of 3H-furo [3,4-c]pyrazoles and 3H-thieno[3,4-c]pyrazoles were prepared in an attempt to isolate examples of cyclopropane-fused thiophenes and furans.
Payne, Alan
core   +2 more sources

Nano-ZnO Catalyzed Green and Efficient One-Pot Four-Component Synthesis of Pyranopyrazoles

Journal of Chemistry, 2013
An efficient zinc oxide nanoparticle catalyzed one-pot, four-component synthesis of 6-amino-3-methyl-5-cyano-4-aryl-1,4-dihydropyrano[2,3-c]pyrazoles from aromatic aldehyde, malononitrile, ethyl acetoacetate, and hydrazine hydrate in aqueous medium is ...
Sunil U. Tekale, Sushma S. Kauthale, Kavita M. Jadhav, Rajendra P. Pawar   +3 more
doaj   +1 more source

Regioselective Synthesis of C3-Hydroxyarylated Pyrazoles

, 2021
Pyrazoles are ubiquitous structures in medicinal chemistry. We report the first regioselective route to C3-hydroxyarylated pyrazoles obtained through reaction of pyrazole N-oxides with arynes using mild conditions.
Darren J. Derksen, Jeffrey F. Van Humbeck, Evgueni Gorobets (2741056), Darren J. Derksen (2297485), Leonie O’Sullivan, Benjamin S. Gelfand (1578766), Leonie O’Sullivan (11836729), Duncan K. Brownsey, Evgueni Gorobets, Jeffrey F. Van Humbeck (11836735), Ketul V. Patel (3423740), Duncan K. Brownsey (11836732), Ben C. Rowley (4818576), Benjamin S. Gelfand, Ketul V. Patel, Ben C. Rowley   +15 more
core   +1 more source

Origin of Enhanced Efficiency and Reduced Roll‐Off in Organic Light‐Emitting Diodes Based on Pt(II) Complexes

Advanced Science, EarlyView.
Controlled Pt–Pt fine structure in square‐planar Pt(II) complexes governs metal–metal‐to‐ligand charge‐transfer (MMLCT) state formation, exciton dynamics, and organic light‐emitting diode performance. Short Pt–Pt contacts in Pt(fppz)2 enable coherent metal–metal coupling, sub‐microsecond emission and an external quantum efficiency of 29%, whereas ...
Atul Shukla, Sarah K. M. McGregor, Julian A. Steele, Innes K. Gale, Kiyoshi Miyata, Monirul Hassan, Christian McDonald, Romain J. Lepage, Eduardo Solano, Pilankatta K. Ramya, Cherumuttathu H. Suresh, Takumi Ehara, Chihaya Adachi, Ken Onda, Shih‐Chun Lo, Ebinazar B. Namdas   +15 more
wiley   +1 more source

Revisiting the Structure and Chemistry of 3(5)-Substituted Pyrazoles

Molecules, 2019
Pyrazoles are known as versatile scaffolds in organic synthesis and medicinal chemistry, often used as starting materials for the preparation of more complex heterocyclic systems with relevance in the pharmaceutical field.
A. Secrieru, P. O'Neill, M. Cristiano
semanticscholar   +1 more source

Regioselective synthesis of 1-aryl-3,4-substituted/annulated-5-(methylthio)pyrazoles and 1-aryl-3-(methylthio)-4,5-substituted/annulated pyrazoles

, 2005
Highly efficient and regioselective synthesis of 1-aryl-3,4-substituted/annulated-5-(methylthio)pyrazoles and 1-aryl-3-(methylthio)-4,5-substituted/annulated pyrazoles has been reported via cyclocondensation of arylhydrazines with either α-oxoketene ...
Peruncheralathan, S., Ila, H., Junjappa, H., Khan, T. A.   +3 more
core   +1 more source

Lewis Acid‐Catalyzed Strain‐Enabled (3+3) Annulation of Bicyclo[1.1.0]Butanes With Indolylalcohols: Synthesis of Indole‐Fused Aza‐Bicyclo[3.1.1]Heptanes

Advanced Science, EarlyView.
Bicyclo[1.1.0]butanes undergo a Lewis acid‐catalyzed formal (3 + 3) annulation with indolyl alcohols to furnish indole‐fused aza‐bicyclo[3.1.1]heptanes. Strain‐release‐driven C‐C bond formation, followed by C‐N bond formation via ring expansion, enables the rapid assembly of rigid, sp3‐rich bicyclic architectures under mild reaction conditions ...
Mainak Dey, Tuhin Subhra Das Mahapatra, Pragya Sharma, Manoj V. Mane, Chinmoy Kumar Hazra   +4 more
wiley   +1 more source

Pyrazoles as potential anti-angiogenesis agents: A contemporary overview

Frontiers in Chemistry, 2014
Angiogenesis is a mulit-step process by which new blood vessels are formed from preexisting vasculature. It is a key rate limiting factor in tumor growth since new blood vessels are necessary to increase tumor size. In this context it has been shown that
Konstantinos M Kasiotis, Evangelia N Tzanetou, Serkos A Haroutounian   +2 more
doaj   +1 more source

Synthesis of Pyrazoles from 1,3-Diols via Hydrogen Transfer Catalysis

, 2016
1,3-Diols engage in ruthenium-catalyzed hydrogen transfer in the presence of alkyl hydrazines to provide 1,4-disubstituted pyrazoles.
Andrew C. Flick (1633114), Alexandria P. Taylor (1633120), Robert E. Kyne (1633123), Daniel C. Schmitt (1633117)   +3 more
core   +1 more source

Synthesis and Antimicrobial Activity of Some New Pyrazoles, Fused Pyrazolo[3,4-d]-pyrimidine and 1,2-Dihydroimidazo-[2,1-c][1,2,4]triazin-6-one Derivatives

Molecules, 2011
A novel series of 7,7-diphenyl-1,2-dihydroimidazo[2,1-c][1,2,4]triazin-6(7H)-one 6a–h, were easily prepared via reactions of novel 2-hydrazinyl-4,4-diphenyl-1H-imidazol-5(4H)-one (2) with hydrazonoyl halides 3a–h.
Huwaida M.E. Hassaneen, Sobhi Mohamed Gomha   +1 more
doaj   +1 more source