Synthesis of [1,2,4]triazolo[4,3-b]pyridazine-3-carboxylic acids

摘要

The first synthesis of 6-substituted-[1,2,4]triazolo[4,3-b]pyridazien-3-carboxylic acids 2a-c was carried out by an enzymatic hydrolysis of alkyl 6-substituted-[1,2,4]triazolo[4,3-b]pyridazine-3-carboxylates 1 by #alpha#-chymotrypsin (EC 3.4.21.1) immobilized on a polyacrylamide-type bead support (ACRYLEX C-100).Earlier the synthesis of these compounds failed owing to ready decarboxylation of the products.During enzymatic hydrolysis decarbxylation was only a side reaction.