. . "Additionally, since the naphthofuran backbone is a part of some natural compounds such as maturin, maturin acetate and 14-methoxydehydrocacalohastine, and novel strategies for the synthesis of naphthofuran backbone continue to receive considerable attention in the field of synthetic organic chemistry,45-47 we also attempted the reaction of 1 with 2-hydroxy-1-naphthaldehyde (2j) (Scheme 3) under si" . .