Three new compounds including two flavonoids and a new 2-phenylbenzofuran, named morunigrols A-C (1-3), together with three known compounds albafuran A (4), albafuran B (5), and mulberrofuran L (6), have been isolated from the barks of Morus nigra. Their structures have been elucidated by
Bioassay-guided fractionation of the chloroform-soluble fraction of Morus bombycis, using an in vitro PTP1B inhibitory assay led to the identification of three 2-arylbenzofurans, albafuran A (1), mulberrofuran W (2) and mulberrofuran D (6), along with three chalcone-derived Diels-Alder products,