title: Tetracyclic triterpenoids from the leaves of Azadirachta indica and their insecticidal activities.
abstract: A new tetranortriterpenoid, meliatetraolenone [24,25,26,27-tetranor-apotirucalla-(apoeupha)-6alpha-O-methyl, 7alpha-senecioyl(7-deacetyl)-11alpha,12alpha,21,23-tetrahydroxy-21,23-epoxy-2,14,20(22)-trien-1,16-dione] (1) was isolated from the methanolic extract of fresh leaves of Azadirachta indica along with the known compound odoratone (3) which was hitherto unreported from this source. Their structures have been elucidated by spectral studies including 2D NMR. The insecticidal activities of 1 as well as those of odoratone (3) are reported. 1 and odoratone both showed mortality on fourth instar larvae of mosquitoes (Anopheles stephensi) with LC(50) values of 16 and 154 ppm, respectively.
authors.affiliation: H. E. J. Research Institute of Chemistry, University of Karachi, Pakistan. bina@khi.comsats.net.pk
authors.forename: Bina Shaheen
authors.initials: BS
authors.lastname: Siddiqui
authors.forename: Farhana
authors.initials: F
authors.lastname: Afshan
authors.forename: Tahsin
authors.initials: T
authors.lastname: Gulzar
authors.forename: Razia
authors.initials: R
authors.lastname: Sultana
authors.forename: Syed Naeemul-Hassan
authors.initials: SN
authors.lastname: Naqvi
authors.forename: Rajput Mohammad
authors.initials: RM
authors.lastname: Tariq
mesh_terms: D000818:Animals; D031601:Azadirachta; D009033:Culicidae / Q000187:drug effects; D007306:Insecticides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D018515:Plant Leaves; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D007306:Insecticides; D010936:Plant Extracts; D014315:Triterpenes