Naturally occurring benzofuran: isolation, structure elucidation and total synthesis of 5-(3-hydroxypropyl)-7-methoxy-2-(3′-methoxy-4′-hydroxyphenyl)-3-benzo[b]furancarbaldehyde, a novel adenosine A1 receptor ligand isolated from salvia miltiorrhiza bunge (danshen)

Abstract A naturally occurring benzofuran, namely 5-(3-hydroxypropyl)-7-methoxy-2-(3′-methoxy-4′-hydroxyphenyl)-3-benzo[ b ]furancarbaldehyde was isolated from the roots of S. miltiorrhiza Bunge “Danshen”. Its structure was established by means of spectroscopic methods as well as by a total synthesis. Both the natural and the synthetic compounds showed a high potency (IC 50 = 17 nM and 10 nM, respectively) in the bovine adenosine A 1 radioligand binding. The title compound was isolated from the root of S. miltiorrhiza Bunge (Danshen) and its structure was established by spectroscopic methods as well as by a total synthesis.