[摘要]：As part of interest in the synthesis of benzannelated heterocycles from ortho-substituted benzylfurans, recyclization of [2-(hydroxymethyl)aryl]difurylmethanes was studied. Under acidic conditions, the 2-hydroxymethyl group in these compds. acts as a nucleophile and tetracyclic isochromene derivs. are formed via a recyclization-cyclization tandem sequence. Alternatively, these compds. can be synthesized by redn. of the corresponding isochromone derivs. with LiAlH4. Potent biol. active analogs of cannabinoids were also obtained by interaction of isochromone derivs. with excess of MeMgI.
