title: New amide alkaloids from the roots of Piper nigrum.
abstract: Seven new amide alkaloids, named N-isobutyl-4-hexanoyl-4-hydroxypyrrolidin-1-one (1), (+/-)-erythro-1-(1-oxo-4,5-dihydroxy-2E-decaenyl)piperidine (2), (+/-)-threo-1-(1- oxo-4,5-dihydroxy-2E-decaenyl)piperidine (3), (+/-)-threo-N-isobutyl-4,5-dihydroxy-2E-octaenamide (4), 1-(1,6-dioxo-2E,4E-decadienyl)piperidine (5), 1-[1-oxo-3(3,4-methylenedioxy-5-methoxyphenyl)-2Z-propenyl]piperidine (6), and 1-[1-oxo-5(3,4-methylenedioxyphenyl)-2Z,4E-pentadienyl]pyrrolidine (7), were isolated from the roots of Piper nigrum, together with 32 known amides. Their structures were elucidated on the basis of spectroscopic analysis and chemical evidence.
authors.affiliation: Faculty of Pharmaceutical Science, Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510, Japan.
authors.forename: Kun
authors.initials: K
authors.lastname: Wei
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Kazuo
authors.initials: K
authors.lastname: Koike
authors.forename: Yuping
authors.initials: Y
authors.lastname: Pei
authors.forename: Yingjie
authors.initials: Y
authors.lastname: Chen
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Nikaido
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification*; D000577:Amides / Q000737:chemistry / Q000302:isolation & purification*; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D029222:Piper nigrum / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000470:Alkaloids; D000577:Amides; D004365:Drugs, Chinese Herbal