A simple and efficient approach to the synthesis of 4H-furo[3,4-b]pyrans via a three-component reaction of isocyanides

A three-component reaction of an isocyanide, a dialkyl acetylenedicarboxylate, and tetronic acid in dichloromethane at room temperature afforded 4H-furo[3,4-b]pyran derivatives. These compounds are closely related with ring systems, TAN-2483B, TAN-2483A, and FD-211 which have a broad spectrum of biological activity.