SYNTHESIS OF NOVEL RING-SYSTEMS - SYNTHESIS OF IMIDAZO[1,2-C]-1,2,4-TRIAZOLO[4,3-A]PYRIMIDO[5',4' 4,5]THIENO[2,3-E]PYRIMIDINE DERIVATIVES/

A series of partially hydrogenated [1,2-c]pyrimido[5',4':4,5]thieno[2, 3-e]pyrimidines (5-11) have been synthesized from the o-aminonitrile 3 through the reaction with ethylene diamine and subsequent condensatio n of the resulting intermediate 4 with orthoester, carbon disulfide an d aldehydes. The triazola derivatives 13-16 were achieved through the reaction of the hydrazino compound 12 with reagents such as acetic anh ydride, ethyl chloroformate and carbon disulfide.