title: Three cyclooctapeptides and one glycoside from Microtoena prainiana.
abstract: Three new cyclic octapeptides, microtoenins A-C (1-3), and a new glycoside, 3'''-O-methylcrenatoside (4), along with several known compounds, were isolated from the ethanolic extract of the stems of Microtoena prainiana. Their structures were determined by spectral and chemical evidence. At a concentration of 0.01 mg/mL, 3'''-O-methylcrenatoside (4), crenatoside (5), and isocrenatoside (6) inhibited angiotensin converting enzyme (ACE) activity by more than 30%.
authors.affiliation: West China School of Pharmacy, Sichuan University, Chengdu 610041, People's Republic of China.
authors.forename: Chong-Qian
authors.initials: CQ
authors.lastname: Li
authors.forename: Bo-Gang
authors.initials: BG
authors.lastname: Li
authors.forename: Hua-Yi
authors.initials: HY
authors.lastname: Qi
authors.forename: Qi-Lin
authors.initials: QL
authors.lastname: Li
authors.forename: Feng-Peng
authors.initials: FP
authors.lastname: Wang
authors.forename: Guo-Lin
authors.initials: GL
authors.lastname: Zhang
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D019686:Lamiaceae / Q000737:chemistry*; D015394:Molecular Structure; D010456:Peptides, Cyclic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D018547:Plant Stems / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D012235:Rhodamines
chemical_list: D000596:Amino Acids; D000806:Angiotensin-Converting Enzyme Inhibitors; D004365:Drugs, Chinese Herbal; D006027:Glycosides; D010456:Peptides, Cyclic; D012235:Rhodamines; C487919:microtoenin A; C487920:microtoenin B; C487921:microtoenin C; C022027:lissamine rhodamine B