Abstract
A short and efficient route to 1,4-substituted 2-aminoimidazole alkaloids starting from the easily accessible 2-alkylaminopyrimidines and α-bromo aldehydes is reported. The formation of the intermediate imidazo[1,2-a ]pyrimidinium salts and subsequent cleavage were facilitated by microwave irradiation. Marine sponge alkaloids preclathridines A, C and isonaamines A, C, D were obtained in high yields using the optimized one-pot two-step procedure.
Key words
natural products - ring opening - cleavage - imidazo[1,2-a ]pyrimidin-1-ium salts - 2-aminoimidazoles
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