Thermal cyclization of nonconjugated aryl-yne-carbodiimide furnishing a dibenzonaphthyridine derivative

Abstract

The reagent-free C2-C7 thermal cyclization of a nonconjugated aryl-yne-carbodiimide yielded a dibenzo- [b,g][1,8]naphthyridine derivative, whose congeners are known to possess fascinating pharmacological properties. This is the first heteroaromatic compound prepared by the thermal cycloaromatization of "nonconjugated" aryl-ynes. © 2009 Pharmaceutical Society of Japan.