Synthesis of Dispiro[indoline-3,3′-pyrrolo[2,1-a]isoquinoline-1′,2′′-thiazolo[3,2-a]pyrimidine] Derivatives via Cycloaddition Reactions

Abstract— The 1,3-dipolar cycloaddition reaction of ethyl (Z)-2-(2-methoxy-2-oxoethylidene)-7-methyl-3-oxo-5-aryl-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate and azomethine ylide which generated in situ by the reaction of isatin and 1,2,3,4-tetrahydroisoquinoline afforded novel 6′′-ethyl 2′-methyl-5′′-(aryl)-7′′-methyl-2,3′′-dioxo-6′,10b′-dihydro-2′H,3′′H,5′H,5′′H-dispiro[indoline-3,3′-pyrrolo[2,1-a]isoquinoline-1′,2′′-thiazolo[3,2-a]pyrimidine]-2′,6′′-dicarboxylate in moderate yields. The structures of all the products were characterized thoroughly by NMR, IR, HRMS together with X-ray crystallographic analysis.