647828-98-6

Upstream product

• 647828-96-4 5-acetyl-3-amino-4-(4'-methoxyphenyl)-6-methyl-thieno[2,3-b]pyridine-2-carboxylic acid 
• 121104-38-9 5-acetyl-3-cyano-4-(4-methoxyphenyl)-6-methylpyridine-2(1H)-thione 
• 233276-72-7 5-acetyl-3-amino-4-(4-methoxy-phenyl)-6-methyl-thieno[2,3-b]pyridine-2-carboxylic acid ethyl ester 
• 647828-89-5 [5-acetyl-3-cyano-4-(4-methoxy-phenyl)-6-methyl-pyridin-2-ylsulfanyl]-acetic acid ethyl ester 

Downstream Products

• 647829-24-1 5-Acetyl-4-(4-methoxy-phenyl)-6-methyl-2-[1-phenyl-meth-(E)-ylidene]-thieno[2,3-b]pyridin-3-one 

Relevant academic research and scientific papers

Synthesis of New Thienopyridines, Pyridothienopyrimidines and Pyranothienopyridines with Anticipated Biological Activity

5-Acetyl-4-aryl-3-cyano-6-methylpyridine-2(1H)-thiones (1a,b) were reacted with ethyl chloroacetate to give ethyl 5-acetyl-4-aryl-3-cyano-6-methylpyridin-2-ylthio) acetates (2a,2b) which, in turn, underwent intramolecular Thorpe-Ziegler cyclization to furnish ethyl 5-acetyl-3-amino-4-aryl-6-methylthieno[2,3-b]pyridine-2-carboxylates (3a,b). The reaction of esters 2a,b with hydrazine hydrate in refluxing ethanol produced (5-acetyl-4-aryl-3-cyano-6-methylpyridin-2-ylthio)acethydrazides (4a,b). When the latter reaction was performed under neat conditions, the products were identified as 5-acetyl-3-amino-4-aryl-6-methylthieno[2,3-b]pyridine-2-carbohydrazides (5a,b). Saponification of o-aminoester 3a gave the corresponding acid 13. The compounds 4a,b,5a,b and 13 were used as key intermediates in the synthesis of the target compounds.