RESUMO
Three new iridoid glycosides, epiasperuloside (1), epipaederosidic acid (2), and epipaederoside (3), together with 7 known compounds, were isolated from the 85% ethanol extract of the leaves of Saprosma ternatum Hook. f. Their structures were determined by application of spectroscopic (NMR, MS) and chemical methodologies. The antioxidant activity was evaluated for all isolates in terms of both DPPH and ABTS bioassays. Epiasperuloside (1) showed some antioxidant activity.
Assuntos
Antioxidantes/farmacologia , Glucosídeos Iridoides/farmacologia , Rubiaceae/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Glucosídeos Iridoides/química , Glucosídeos Iridoides/isolamento & purificação , Glicosídeos Iridoides , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/químicaRESUMO
Two new holostane-type triterpene glycosides, named pentactasides I (1) and II (2), and a new natural product, pentactaside III (3), together with two known glycosides, philinopsides A (4) and B (5), were isolated from the sea cucumber Pentacta quadrangularis. Their structures were elucidated by extensive spectroscopic analysis and chemical evidences. Compounds 1 and 2 possess the same trisaccharide moiety which is a rare structural feature among naturally occurring sea cucumber glycosides and has been infrequently reported, while 3 is a sulfated diglycoside. All the glycosides showed significant in vitro cytotoxicities against six tumor cell lines (P-388, A-549, MCF-7, MKN-28, HCT-116, and U87MG) with IC(50) in the range of 0.60-3.95 µM.
Assuntos
Antineoplásicos/uso terapêutico , Glicosídeos/uso terapêutico , Neoplasias/tratamento farmacológico , Pepinos-do-Mar/química , Triterpenos/uso terapêutico , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Humanos , Estrutura Molecular , Saponinas/isolamento & purificação , Saponinas/uso terapêutico , Triterpenos/isolamento & purificação , Triterpenos/farmacologiaRESUMO
OBJECTIVE: To study the chemical constituents of Ishige okamurai. METHOD: Compounds were isolated by Pyricularia oryzae bioassay-guided fractionation method in combination with extraction and partitionation as well as multi-chromatography. Their structures were determined by spectral analysis and chemical evidence. RESULT: Seven compounds were obtained and identified as (2S)-1-O-palmitoyl-2-O-(11Z-octadecenoyl)-3-O-beta-D-galacto-pyranosyl glycerol (I), (2S)-1-O-palmitoyl-2-O-myristoyl-3-O-(6-sulfo-alpha-D- quinovopyranosyl) glycerol (II), (2S)-1-O-palmitoyl-2-O-palmitoyl-3-O-(6'-sulfo-alpha-D- quinovopyranosyl) glycerol (III) and (2S)-1-O-palmitoyl-2-O-(11Z-octadecenoyl)-3-O-(6'-sulfo-alpha-D- quinovopyranosyl) glycerol (IV), stearic acid (V), methyl myristate(VI) and palmitic acid (VII). CONCLUSION: Compounds I-VI were isolated from the alga for the first time while I, II and IV are new natural products. I-IV showed activity causing morphological abnormality of P. oryzae mycelia.