THIAZOLE PYRIDAZINONES AS ADENOSINE ANTAGONISTS

摘要

A thiazole derivative of the formula (I):wherein R is 1-optiona lly substituted-6-oxo-1,6-dihydro-3-pyridazinyl, R' is an optionally substituted phenyl, and R<2> is hydrogen, a group of the formula (i): wherein R<4> is hydrogen, lower alkyl or lower alkenyl, and R<5> is hydrogen, optionally substituted lower alkyl, acyl, cyclo(lower)alkyl, lower alkenyl, optionally substituted aryl or heterocyclic, or a group of the formula (ii): wherein X is oxygen or sulfur, R<8> is hydrogen or lower alkyl, R<9> is hydrogen, optionally substituted lower alkyl, cyclo(lower)alkyl, lower alkoxy or mono- or di-lower alkylamino or R<8> and R<9> may be combine together to form optionally substituted saturated N-containing heterocyclic, or a salt thereof._The compounds are useful as Adenosine antagonists. The application also discloses an improved process for the preparation of pyridazinones (XII-1)