title: Enzyme inhibitory constituents from Duranta repens.
abstract: Isoprenylated flavonoids 5,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-3,6,4'-trimethoxyflavone (1), 3,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-5,6,4'-trimethoxyflavone (2) and an isoprenylated acetophenone derivative (3) have been isolated from Duranta repens along with known compounds, 5-hydroxy-3,6,7,4'-tetramethoxyflavone (4), rosenonolactone (5), 6,7-dimethoxycoumarin (6), 5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (7) and 5alpha,8alpha-epidioxyergosta-6,9(11),22-trien-3beta-ol (8), isolated for the first time from this species. Their structures and the relative configuration were determined by spectroscopic methods (1H- and 13C-NMR, IR, UV and MS) and two-dimensional (2D)-NMR experiments. The compounds 1-5 showed inhibitory activity against prolyl endopeptidase while 4 and 5 were also active against thrombin.
authors.affiliation: International Center of Chemical Sciences, HEJ Research Institute of Chemistry, University of Karachi, Pakistan.
authors.forename: Itrat
authors.initials: I
authors.lastname: Anis
authors.forename: Saeed
authors.initials: S
authors.lastname: Ahmed
authors.forename: Abdul
authors.initials: A
authors.lastname: Malik
authors.forename: Amsha
authors.initials: A
authors.lastname: Yasin
authors.forename: M Iqbal
authors.initials: MI
authors.lastname: Choudary
mesh_terms: D000818:Animals; D002417:Cattle; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D010936:Plant Extracts / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D000085822:Prolyl Oligopeptidases; D012697:Serine Endopeptidases / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors / Q000737:chemistry / Q000302:isolation & purification; D013329:Structure-Activity Relationship; D013917:Thrombin / Q000037:antagonists & inhibitors*; D029648:Verbenaceae / Q000737:chemistry*
chemical_list: D004791:Enzyme Inhibitors; D010936:Plant Extracts; D015842:Serine Proteinase Inhibitors; D012697:Serine Endopeptidases; D000085822:Prolyl Oligopeptidases; D013917:Thrombin