Construction of a polyheterocyclic benzopyran library with diverse core skeletons through diversity-oriented synthesis pathway.

In this study, a divergent and practical solid-phase parallel diversity-oriented synthesis (DOS) strategy was successfully applied for the construction of five discrete core skeletons embedded with privileged benzopyranyl substructure. The diversity of these core skeletons was expanded through the introduction of various substituents at the R, R(1), and R(2) positions from a single key intermediate in five different pathways. More importantly, we efficiently maximized the molecular diversity through the transformation of the core skeleton itself by using the library-to-library concept and created a distinctively different collection of small molecules with the same building blocks. A 434-member polyheterocyclic benzopyran library was constructed on a scale of about 10 mg with the potential for further diversification. Without further purification, the average purity of the library is 85%.