New prenylated isoflavonoids as protein tyrosine phosphatase 1B (PTP1B) inhibitors from Erythrina addisoniae

Four new (1-4) along with 2 known prenylated isoflavonoids (5-6) were isolated from an EtOAc extract of the root of Erythrina addisoniae. All the isolates were evaluated for their inhibitory effects on protein tyrosine phosphatase 1B (PTP1B), as well as their growth inhibition on MCF7, adriamycin-resistant MCF7 (MCF7/ADR), and MDA-MB-231 breast cancer cell lines. Compounds which exhibited PTP1B inhibitory activity (IC50 values ranging from 4.6 ± 0.3 to 24.2 ± 2.1 μM) showed potential cytotoxic activity (IC50 values ranging from 3.97 ± 0.17 to 11.4 ± 1.9 μM).