Phytochemical study of four plants from the family Myrsinaceae

International audienceFour Peruvian plants (Cybianthus magnus, Myrsine latifolia, Myrsine congesta and Myrsine sessiliflora) belonging to the Myrsinaceae family have been studied in search of molecules with antileishmanial activity. From the hydromethanolic extract of three parts of each plant (leaves, stem and roots) 10 compounds were purified and identified. The purification was performed using chromatographic methods (HPLC; semi preparative chromatography) and the structure elucidation was accomplished by 1D, 2D NMR spectra (1H-1H, 13C, DEPT, COSY, HSQC, HMBC). One new compound was isolated and identified as 5-alkylresorcinolglucoside, named Cybianthoside A, from C. magnus. From the other plants, six flavonoids were isolated: (-) catechin, catechin-3-O-rhamnopyranoside , quercetin-3-O-rhamnopyranoside, isorhamnetin-3-O-rhamnopyranoside, quercetin-3-O-arabinopyranoside and quercetin-3-O-arabinofuranoside ; one lignan: lyoniresinol-9'-O-glucopyranoside ; one resorcinol derivative: 12'Z-5-heptadec-12'-enylresorcinol and two chromanes: myrsinoic acid B and myrsinoic B methyl ester. Extracts and fractions were evaluated for their antileishmanial activity but no activity was detected

Etude phytochimique de Poraqueiba sericea.

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Triterpenoid saponins from the stem bark of Caryocar villosum

Five triterpenoid saponins, caryocarosides II-22 (3), III-22 (4), II-23 (5), III-23 (6), and II-24 (7), have been isolated from the methanol extract of the stem bark of Caryocar villosum, along with two known saponins (1-2). The seven saponins are glucuronides of hederagenin (II) or bayogenin (III). Caryocaroside II-24 (7) is an unusual galloyl ester saponin acylated on the sugar chain attached to C-28, the 3-O-alpha-L-rhamnopyranosyl-(1 -> 3)-beta-D-galactopyranosyl-(1 -> 3)-beta-D-glueuronopyranosyl hederagenin-28-O-[2-O-galloyi-beta-D-glucopyranosyl] ester. The structures of the saponins were established on the basis of extensive NMR (C-13, H-1, COSY, TOCSY, HSQC, HMBC and ROESY) and ESI-MS studies. The cytotoxic activity of saponins 2 and 3 was evaluated in vitro against human keratinocytes. The DOPA-oxidase inhibition and the lipolytic activities were evaluated ex vivo using an explant of human adipose tissue. (c) 2006 Elsevier Ltd. All rights reserved

Zebiriosides A-P, oleanane saponins isolated by LC-SPE-NMR hyphenation from the roots of Dendrobangia boliviana

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A new 5-alkylresorcinol glucoside derivative from Cybianthus magnus

One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (2, 3 isolated from C. magnus; 4-7, 10 and 11 isolated from Myrsine latifolia; 4, 8 and 9 isolated from Myrsine sessiflora; 6, 7, 10, 12 and 13 isolated from Myrsine congesta). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of Grevillea robusta. Since resorcinols are known to exhibit strong cytotoxic activity, compounds 1 and 2 were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity in vitro and compounds 3-13 were tested for their antileishmanial activity. Compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100M for all tested cell lines. Compounds 3-13 were not active against Leishmania amazonensis amastigotes

A new 5-alkylresorcinol glucoside derivative from <i>Cybianthus magnus</i>

<div><p>One new 5-alkylresorcinol glucoside (<b>1</b>) was isolated from leaves of <i>Cybianthus magnus,</i> along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (<b>2, 3</b> isolated from <i>C. magnus</i>; <b>4</b>–<b>7</b>, <b>10</b> and <b>11</b> isolated from <i>Myrsine latifolia</i>; <b>4</b>, <b>8</b> and <b>9</b> isolated from <i>Myrsine sessiflora</i>; <b>6</b>, <b>7</b>, <b>10</b>, <b>12</b> and <b>13</b> isolated from <i>Myrsine congesta</i>). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of <i>Grevillea robusta</i>. Since resorcinols are known to exhibit strong cytotoxic activity, compounds <b>1</b> and <b>2</b> were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity <i>in vitro</i> and compounds <b>3</b>–<b>13</b> were tested for their antileishmanial activity. Compound <b>2</b> displayed a strong cytotoxic activity with IC₅₀ values ranging between 22 and 100 μM for all tested cell lines. Compounds <b>3</b>–<b>13</b> were not active against <i>Leishmania amazonensis</i> amastigotes.</p></div