Synthesis of naphtho[2,3-b][1,4]dioxin, 2-substituted naphtho[2,3-b][1,4]dioxins and 2,3-disubstituted naphtho[2,3-b][1,4]dioxins

In view of their potential biological properties, various 2,3-disubstituted naphtho[2,3-b][1,4]dioxins and 2-substituted furo[3,4-b]naphtho[2,3-e][1,4]dioxins have been synthesized. These novel compounds are intermediates to further extended heterocyclic systems.