title: Antimicrobially active isoquinoline alkaloids from Litsea cubeba.
abstract: Bioassay-guided fractionation of the alkaloidal extract of the aerial part of Litsea cubeba led to the isolation of two new isoquinoline alkaloids, (+)- N-(methoxycarbonyl)-N-norboldine (1) and (+)-isoboldine beta-N-oxide (2), together with 11 known analogues (3-13). Their structures were established by extensive spectroscopic techniques and by comparing spectroscopic data with those in the literature. Compounds 1 and 4 showed antimicrobial activities. This is the first report on the presence of compounds 1, 2, 6, 8, 9, 11, and 12 in this plant and on the antimicrobial activities of 1 and 4. The bioactivities of isoquinoline alkaloids are also at least partly responsible for the pharmacological function of the folk medicinal plant Litsea cubeba.
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, PR China.
authors.forename: Tao
authors.initials: T
authors.lastname: Feng
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
authors.forename: Xiang-Hai
authors.initials: XH
authors.lastname: Cai
authors.forename: Zhi-Zhi
authors.initials: ZZ
authors.lastname: Du
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Luo
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005591:Chemical Fractionation; D005658:Fungi / Q000187:drug effects; D007546:Isoquinolines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D032862:Litsea / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D009169:Mycobacterium tuberculosis / Q000187:drug effects; D035261:Plant Components, Aerial / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000470:Alkaloids; D000890:Anti-Infective Agents; D007546:Isoquinolines; D010936:Plant Extracts