Patent ID: 6372915
Filing Date: 2002-04-16
Classification: A61P,C07D

Abstract:
A production method of an oxazole compound of the formula [7]wherein R1 is an optionally substituted cycloalkyl group, an optionally substituted aryl group or an optionally substituted heterocyclic group, R2 is a lower allyl or a halogenated lower alkyl and R3 is a halogen atom or a hydrogen atom, comprising reacting a compound of the formula [1]wherein R1 and R2 are as defined above, with thionyl chloride in an inert solvent in the presence of a base, to give an oxazolone compound of the formula [2]wherein R1 and R2 are as defined above, subsequently reacting this compound with a compound of the formula [3]wherein R3 is as defined above and X is a halogen atom, in ethyl acetate in the presence of a magnesium salt and a base to give a compound of the formula [4]wherein R1, R2 and R3 are as defined above, subjecting this compound to hydrolysis and decarboxylation with an acid to give a compound of the formula [5]wherein R1, R2 and R3 are as defined above, subjecting this compound to cyclization and sulfonation with a sulfonating agent and chlorination with thionyl chloride to give a compound of the formula [6]wherein R1, R2 and R3 are as defined above, and subjecting this compound to amidation in ethyl acetate with aqueous ammonia.