title: Diterpenes from Leucas aspera inhibiting prostaglandin-induced contractions.
abstract: Investigation of the inhibitory fraction of Leucas aspera on prostaglandin-induced contraction in guinea pig ileum provided four new diterpenes, leucasperones A (1) and B (2) and leucasperols A (3) and B (4), and three new isopimarane glycosides, leucasperosides A, B, and C (5-7), together with the known compounds asperphenamate, maslinic acid, (-)-isololiolide, and linifolioside. The structures of the compounds were determined by detailed spectroscopic analysis. The configurations of 1 and 2 and the acetylated derivatives of 3 and 4 were determined by differential NOE analysis and CD data. Leucasperone A (1), leucasperosides A (5) and B (6), and linifolioside showed inhibition of prostaglandin-induced contractions.
authors.affiliation: Pharmacy Discipline, Life Science School, Khulna University, Khulna-9208, Bangladesh, Faculty of Pharmaceutical Sciences, Josai International University, 1 Gumyo, Togane, Chiba 283-8555, Japan.
authors.forename: Samir Kumar
authors.initials: SK
authors.lastname: Sadhu
authors.forename: Emi
authors.initials: E
authors.lastname: Okuyama
authors.forename: Haruhiro
authors.initials: H
authors.lastname: Fujimoto
authors.forename: Masami
authors.initials: M
authors.lastname: Ishibashi
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001459:Bangladesh; D001713:Biphenyl Compounds; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects; D019686:Lamiaceae / Q000737:chemistry*; D008297:Male; D015394:Molecular Structure; D010851:Picrates / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D011448:Prostaglandin Antagonists / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D004224:Diterpenes; D006027:Glycosides; D010851:Picrates; D011448:Prostaglandin Antagonists; C004931:1,1-diphenyl-2-picrylhydrazyl