26502-53-4

Upstream product

• 20954-18-1 2-[(2-Nitro-phenyl)-hydrazono]-3-oxo-butyric acid ethyl ester 

Downstream Products

• 82762-73-0 ethyl 5-allyl-4-allyloxy-1-(o-nitrophenyl)pyrazole-3-carboxylate 
• 82762-70-7 ethyl 5-(2,3-dibromopropyl)-4-hydroxy-1-(o-nitrophenyl)pyrazole-3-carboxylate 
• 82762-67-2 ethyl 5-allyl-4-hydroxy-1-(o-nitrophenyl)pyrazole-3-carboxylate 
• 82762-64-9 ethyl 4-allyloxy-1-(o-nitrophenyl)pyrazole-3-carboxylate 

Relevant academic research and scientific papers

Concise and efficient synthesis of 1H-pyrazoles: Reaction of [hydroxy(tosyloxy)iodo]benzene with ethyl 2,3-dioxobutanoate-2-arylhydrazones

Ethyl 2,3-dioxobutanoate-2-arylhydrazones 1 on treatment with [hydroxy(tosyloxy)iodo]benzene 2 at reflux temperature and followed by heating in the presence of N-ethyldiisopropylamine afforded the cyclized ethyl 1-aryl-4-hydroxy-1H-3-pyrazolecarboxylates 4 in good yield.

Polysubstituted pyrazoles. Part 2: Sulphonamidophenylhydrazone-2-pyrazolin-4-ones and sulphonamidophenylazopyrazoles as potential anticancer agents.

The synthesis of some new derivatives of 1-[4-nitrophenyl]-5-[4-substituted sulphonamidophenylhydrazono]-2-pyrazolin-4-ones and 3,5-dimethyl-4-[4-substituted sulphonamidophenylazo]-pyrazoles is described. Bromination of ethyl 2-[nitrophenylhydrazono]-3-oxobutyrates in dry benzene afforded the 4-bromo derivatives which upon cyclization gave high yields of the 4-hydroxpyrazoles. Many other new intermediates were prepared and the results of the UV and IR spectral studies are discussed.