The first total syntheses of (±)-norphoebine, dehydrophoebine, oxophoebine, dehydrocrebanine, oxocrebanine and uthongine and their cytotoxicity against three human cancer cell lines

<p>The first total syntheses of (±)-norphoebine, dehydrophoebine, oxophoebine, dehydrocrebanine, oxocrebanine and uthongine have been achieved. The crucial step involved the formation of ring C by a microwave-assisted direct biaryl coupling to produce the aporphine skeleton in high yields. The synthetic alkaloids were evaluated for their cytotoxicity against three human cancer cell lines MCF7, KB and NCI-H187. The results showed that uthongine was the best candidate of the series and it exhibited cytotoxicity against a human breast cancer MCF7 line with an IC₅₀ = 3.05 μM</p

A new dihydrobenzofuran lignan and potential <i>α</i>-glucosidase inhibitory activity of isolated compounds from <i>Mitrephora teysmannii</i>

<p>A new dihydrobenzofuran lignan, (2<i>R</i>,3<i>S</i>)-2-(3′,4′-dimethoxyphenyl)-5-(3-hydroxypropyl)-7-methoxy-2,3-dihydrobenzofuran-3-methyl acetate, named as mitredrusin (<b>1</b>), was isolated from the leaves of <i>Mitrephora teysmannii</i> (Annonaceae) together with 12 known compounds including a related dihydrobenzofuran lignan: (−)-3′,4-di-<i>O</i>-methylcedrusin (<b>2</b>), four polyacetylenic acids: 13(<i>E</i>)-octadecene-9,11-diynoic acid (<b>3</b>), 13(<i>E</i>),17-octadecadiene-9,11-diynoic acid (<b>4</b>), octadeca-9,11,13-triynoic acid (<b>5</b>) and octadeca-17-en-9,11,13-triynoic acid (<b>6</b>), five lignans: (−)-eudesmin (<b>7</b>), (−)-epieudesmin (<b>8</b>), (−)-phillygenin (<b>9</b>), magnone A (<b>10</b>) and forsythialan B (<b>11</b>) and two megastigmans: (3<i>S</i>,5<i>R</i>,6<i>S</i>,7<i>E</i>,9<i>R</i>)-7-megastigmene-3,6,9-triol (<b>12</b>) and annoionol A (<b>13</b>). The chemical structures of these compounds were established on the basis of their 1-D and 2-D NMR spectroscopic data. All compounds were evaluated for their <i>α</i>-glucosidase inhibitory activity. Among these isolates, polyacetylenic acids <b>3</b> and <b>4</b> showed more than 20-fold much higher activity compared with that of the antidiabetic drug acarbose.</p

A new acylated triterpene glycoside and cytotoxic constituents from <i>Dolichandrone serrulata</i> (Wall. ex DC.) Seem

In this study, a new acylated triterpene glycoside, 3α-O-stearoyl-28-[2′-stearoyl-α-l-arabinopyranosyl]-olean-12-en-28-oic acid (1), was isolated from the flowers of Dolichandrone serrulata. In addition to this compound, eleven known compounds were also isolated, including a related pentacyclic triterpenoid: ursolic acid (2), two cycloartane triterpenoids: 24-methylenecycloartanol (3) and 24-methylenecycloartane-3,28-diol (4), three cyclohexylethane derivatives: (-)-rengyolone (5), (-)-cleroindicin C (6) and (-)-cleroindicin D (7), an iridoid: 6-O-trans-feruloyl catalpol (8), two phenylethanoid glycosides: salidroside (9) and verbascoside (10), and two steroids: β-sitosterol (11) and β-sitosterol-3-O-β-d-glucopyranoside (12). The chemical structures of these compounds were determined by analysing their HRMS and NMR spectroscopic data. Additionally, their cytotoxic activities against NH22, HCT116, MCF7, MDA-MB-231, and HeLa cell lines were evaluated for all the compounds. Ursolic acid exhibited moderate cytotoxic activity against all cancer cell lines tested, particularly against HN22, MDA-MB-231, MCF-7, and HCT116 cells with IC50 values of approximately 19–34 µM.</p