摘要:
The heterocyclic analogs 5a-f, 16, and 20 of 1-arylnaphthalene lignans were synthesized by Diels-Alder reactions of acetoxy aldehydes 11a-f, 14, and 18 with dimethyl acetylenedicarboxylate. A pathway for formation of 5a-f, 16, and 20 through the intermediacy of heteroaromatic isobenzofurans derived from acetoxy aldehydes is discussed.