268544-89-4

Upstream product

• 471-47-6 oxamic acid 
• 1073-70-7 4-chlorophenylhydrazine hydrochloride 
• 105-45-3 acetoacetic acid methyl ester 
• 127107-00-0 ethyl 2-amino-3-methoxycarbonyl-4-oxo-2-pentanoate 
• 1073-69-4 N-4-chlorophenylhydrazine 
• 268544-84-9 ethyl 1-(4-chlorophenyl)-4-(methoxycarbonyl)-5-methyl-3-pyrazolecarboxylate 

Downstream Products

• 1026591-00-3 3-chlorocarbonyl-1-(4-chloro-phenyl)-5-methyl-1H-pyrazole-4-carboxylic acid methyl ester 
• 268544-99-6 methyl 3-cyclopropylcarboxamido-1-(4-chlorophenyl)-5-methyl-4-pyrazolecarboxylate 
• 268544-94-1 methyl 3-tert-butylcarboxamido-1-(4-chlorophenyl)-5-methyl-4-pyrazolecarboxylate 

Relevant academic research and scientific papers

Expeditious solid-phase synthesis of pyrazoledicarboxylic acid derivatives by functionalization of resin-bound cyanoformate

Esterification of the Wang resin 5 with the monoamide of oxalic acid (oxamic acid, 7) followed by dehydration of the amide function furnishes the resin-bound cyanoformate 9, which can be elaborated by zinc-catalyzed reaction with β-keto esters. The obtained enamino keto diesters 10a-d react with hydrazines affording, after removal from the solid support, fully substituted pyrazoledicarboxylic acids 12a-n. Optimization of the above sequence and the solid-phase synthesis of a small test-library of 1,5-disubstituted pyrazole-3,4-dicarboxylic acid derivatives are described. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.

A new synthetic entry to 3-carboxamido-4-carboxylic acid derivatives of isoxazole and pyrazole

Ethyl 2-amino-3-methoxycarbonyl-4-oxo-2-pentenoate (3) reacts with hydroxylamine or hydrazines to give isoxazole and pyrazole ortho-dicarboxylic acid esters 4 and 5, respectively. Partial hydrolysis of diesters 4 and 5 afforded the corresponding dicarboxy