Bioactive Constituents of <i>Indigofera spicata</i>

Four new flavanones, designated as (+)-5″-deacetylpurpurin (<b>1</b>), (+)-5-methoxypurpurin (<b>2</b>), (2<i>S</i>)-2,3-dihydrotephroglabrin (<b>3</b>), and (2<i>S</i>)-2,3-dihydrotephroapollin C (<b>4</b>), together with two known flavanones (<b>5</b> and <b>6</b>), three known rotenoids (<b>7</b>–<b>9</b>), and one known chalcone (<b>10</b>) were isolated from a chloroform-soluble partition of a methanol extract from the combined flowers, fruits, leaves, and twigs of <i>Indigofera spicata</i>, collected in Vietnam. The compounds were obtained by bioactivity-guided isolation using the HT-29 human colon cancer, 697 human acute lymphoblastic leukemia, and Raji human Burkitt’s lymphoma cell lines. The structures of <b>1</b>–<b>4</b> were established by extensive 1D- and 2D-NMR experiments, and the absolute configurations were determined by the measurement of specific rotations and CD spectra. The cytotoxic activities of the isolated compounds were tested against the HT-29, 697, Raji, and CCD-112CoN human normal colon cells. Also, the quinone reductase induction activities of the isolates were determined using the Hepa 1c1c7 murine hepatoma cell line. In addition, <i>cis</i>-(6aβ,12aβ)-hydroxyrotenone (<b>7</b>) was evaluated in an in vivo hollow fiber bioassay using HT-29, MCF-7 human breast cancer, and MDA-MB-435 human melanoma cells

Caeruleanone A, a Rotenoid with a New Arrangement of the D‑Ring from the Fruits of <i>Millettia caerulea</i>

Caeruleanone A (<b>1</b>), a novel rotenoid with an unprecedented arrangement of the D-ring, was isolated with another two new analogues, caeruleanones B (<b>2</b>) and C (<b>3</b>), together with 11 known rotenoids from the fruits of <i>Millettia caerulea</i>. The structures of the new compounds were determined by spectroscopic data analysis, with that of <b>1</b> being confirmed by single-crystal X-ray diffraction. Compounds <b>2</b> and <b>3</b> displayed potent mitochondrial transmembrane potential inhibitory and quinone reductase induction activities