Cytotoxic Prenylated Isoflavone and Bipterocarpan from Millettia pachyloba

Abstract

Two new compounds, an isoflavone (1, 6-methoxybarbigerone) and a bipterocarpan (2, pachylobin) were isolated from the grains of Millettia pachyloba (Leguminosae), together with seven known compounds, 5-methoxybarbigerone (3), calopogoniumisoflavone B (4), durmillone (5), jamaicin (6), ichthynone (7), (−)-pisatin (8) and (−)-rotenone (9). The structures were established from spectroscopic analyses, including mass spectrometry and 2D‐NMR. Absolute configuration of 2 was proposed based on that of the known compound (−)-pisatine (8). Compounds 1 and 2 exhibited cytotoxicity against KB cells with IC₅₀ values of 2.0 and 17.6 µM, respectively.

Key words

Millettia - Leguminosae - pterocarpan - 6‐methoxybarbigerone - pachylobin - isoflavonoid

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