title: New triterpenoid alkaloid cholinesterase inhibitors from Buxus hyrcana.
abstract: Three new triterpenoid alkaloids, (+)-N-benzoylbuxahyrcanine [(20S)-3beta-benzoylamino-20-dimethylaminobux-9(11)-ene-10alpha-ol] (1), (+)-N-tigloylbuxahyrcanine [(20S)-20-(dimethylamino)-3beta-(2'-methyl-2'-butenoylamino)bux-9(11)-en-10alpha-ol] (2), and (+)-N-isobutyroylbuxahyrcanine [(20S)-20-(dimethylamino)-3beta-(2'-methylpropanoyl)bux-9(11)-en-10alpha-ol] (3), have been isolated from the leaf extracts of Buxus hyrcana collected in Iran. Their structures were determined using spectroscopic methods. The structures of compounds 1 and 2 were unambiguously confirmed by single-crystal X-ray diffraction techniques. Compounds 1-3 were evaluated for their acetylcholinesterase and butyrylcholinesterase inhibitory activities, and compound 2 was found to be active against both enzymes.
authors.affiliation: HEJ Research Institute of Chemistry, University of Karachi, International Center for Chemical Sciences, Karachi-75270, Pakistan. zainraa@digicom.net.pk
authors.forename: M Iqbal
authors.initials: MI
authors.lastname: Choudhary
authors.forename: Salma
authors.initials: S
authors.lastname: Shahnaz
authors.forename: Shehnaz
authors.initials: S
authors.lastname: Parveen
authors.forename: Asaad
authors.initials: A
authors.lastname: Khalid
authors.forename: S Abdul
authors.initials: SA
authors.lastname: Majeed Ayatollahi
authors.lastname: Atta-Ur-Rahman
authors.forename: Masood
authors.initials: M
authors.lastname: Parvez
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002091:Butyrylcholinesterase; D031235:Buxus / Q000737:chemistry*; D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D018360:Crystallography, X-Ray; D020128:Inhibitory Concentration 50; D007492:Iran; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: C478440:(+)-N-benzoylbuxahyrcanine ((20S)-3beta-benzoylamino-20-dimethylaminobux-9(11)-ene-10alpha-ol); C478441:(+)-N-isobutyroylbuxahyrcanine ((20S)-20-(dimethylamino)-3beta-(2'-methylpropanoyl)bux-9(11)-en-10alpha-ol); C478442:(+)-N-tigloylbuxahyrcanine ((20S)-20-(dimethylamino)-3beta-(2'-methyl-2'-butenoylamino)bux-9(11)-en-10alpha-ol); D000470:Alkaloids; D002800:Cholinesterase Inhibitors; D014315:Triterpenes; D002091:Butyrylcholinesterase