RESUMO
Eight new flavonoid-based 3'-O-ß-d-glucopyranosides (1-8) and three new galloyl glucosides (9, 11, 12), were isolated from the aerial parts of Saxifraga spinulosa, along with 25 known compounds. The structures of the new compounds were elucidated by spectroscopic methods. Most of the isolated compounds exhibited potent DPPH radical-scavenging activities. Further, their inhibitory activities were evaluated against Babesia bovis, Babesia bigemina, Babesia caballi, and Theileria equi, protozoan parasites that cause piroplasmosis in livestock. The results indicated that several of these compounds showed growth-inhibitory effects on such organisms that cause piroplasmosis.
Assuntos
Antioxidantes/farmacologia , Babesia/química , Flavonoides/farmacologia , Glicosídeos/farmacologia , Saxifragaceae/química , Theileria/química , Animais , Antioxidantes/química , Flavonoides/química , Glicosídeos/química , Estrutura MolecularRESUMO
Eleven 2,5-diphenyloxazole derivatives (1-11), together with six known isoflavonoid derivatives, were isolated from the roots of Oxytropis lanata. The 2,5-diphenyloxazole (1) obtained proved to be identical to a standard sample used as a scintillator and liquid laser dye. The other oxazole derivatives isolated were found to have one to four hydroxy and/or O-methyl groups in their phenyl rings. Seven of the oxazole derivatives obtained are new (3-9). The inhibitory activity of the isolated compounds was evaluated against Trypanosoma congolense, the causative agent of African trypanosomosis in animals. Oxazoles with di- and trihydroxy groups showed trypanocidal activity, and 2-(2',3'-dihydroxyphenyl)-5-(2â³-hydroxyphenyl)oxazole (4) exhibited the most potent inhibitory activity (IC50 1.0 µM).
Assuntos
Oxazóis/isolamento & purificação , Oxazóis/farmacologia , Oxytropis/química , Raízes de Plantas/química , Tripanossomicidas/isolamento & purificação , Tripanossomicidas/farmacologia , Animais , Concentração Inibidora 50 , Estrutura Molecular , Mongólia , Ressonância Magnética Nuclear Biomolecular , Oxazóis/química , Tripanossomicidas/química , Trypanosoma congolense/efeitos dos fármacosRESUMO
Activity-guided isolation of the n-butanol fraction of Chamaerhodos erecta and water soluble fraction of C. altaica resulted in the isolation of 39 compounds, including new compounds identified as 4,5-dihydroxybenzaldehyde-3-O-ß-D-glucopyranoside (1) from C. erecta and quercetin-3-O-ß-D-glucuronopyranosyl-4'-O-ß-D-glucopyranoside (2) from C. altaica. A total of 37 other compounds were identified based on physico-chemical properties and spectroscopic data. Antioxidative activity was evaluated using a DPPH radical-scavenging method, hyaluronidase inhibitory activity, and advanced glycation end products production inhibitory activity of isolated compounds. Some flavonols (4, 6, 9-11, 14, 15), catechins (18, 19), an amino acid (20), a lignan glucoside (23), and tannins (29-39) exhibited potential a free radical scavenging activity while the new compound (1) showed weak activity. A catechin (18) and some of the tannins (32, 33, 35, 36, 38) had moderate hyaluronidase inhibitory activity. Some of flavonoids and tannins prevented advanced glycation end products production, and the IC50 of compounds 3, 9, 14-16, 33, 34, 36, 38, and 39 were determined.