A new reaction of N-protected 2-bromomethylazoles and tosylmethyl isocyanide (TosMIC) leading to the preparation of azolopyrimidines isdescribed. This domino sequence was used to synthesize the pyrido[3',2':4,5]pyrrolo[1,2-
c]pyrimidine core of alkaloids variolins from 4-methoxy-2-methylpyrrolo[2,3-
b]pyrimidine in two steps.