Compounds from Danshen. Part 7. Regioselective introduction of carbon-3 substituents to 5-alkyl-7-methoxy-2-phenylbenzo[b]furans: synthesis of a novel adenosine A1 receptor ligand and its derivatives
作者:Zhen Yang、Han Biao Liu、Chi Ming Lee、Hson Mou Chang、Henry N. C. Wong
DOI:10.1021/jo00052a046
日期:1992.12
By maintaining the balance between the electronic requirements, the stereochemical restrictions as well as the kinetic and thermodynamic factors, the unprecedented regioselective electrophilic aromatic substitution of formyl and nitro groups to carbon-3 of 5-alkyl-7-methoxy-2-phenylbenzo[b]furans have been achieved. Subsequent transformation of the resulting formyl group into methyl, hydroxymethyl, 1-hydroxyethyl, and cyano groups are also described.