title: Cytotoxic alkaloids from the whole plants of Zephyranthes candida.
abstract: Seven new alkaloids, N-methylhemeanthidine chloride (1), N-methyl-5,6-dihydroplicane (5), O-methylnerinine (6), N-ethoxycarbonylethylcrinasiadine (7), N-ethoxycarbonylpropylcrinasiadine (8), N-phenethylcrinasiadine (9), and N-isopentylcrinasiadine (10), together with eight known alkaloids, hemeanthamin (2), 3-epimacronine (3), (+)-tazettine (4), N-methylcrinasiadine (11), trisphaeridine (12), 5,6-dihydrobicolorine (13), lycorine (14), and nigragillin (15), were isolated from the whole plants of Zephyranthes candida. The structures of the new compounds were established by spectroscopic data interpretation, with single-crystal X-ray diffraction analysis performed on 1. The absolute configuration of 3-epimacronine (3) was determined by single-crystal X-ray diffraction analysis with Cu Kα irradiation. Compounds 1-15 were evaluated for their in vitro cytotoxicity against five human cancer cell lines and the Beas-2B immortalized (noncancerous) human bronchial epithelial cell line. Compounds 1, 2, 9, and 14 exhibited cytotoxicity with IC(50) values ranging from 0.81 to 13 μM with selectivity indices as high as 10 when compared to the Beas-2B cell line.
authors.affiliation: Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, People's Republic of China.
authors.forename: Zengwei
authors.initials: Z
authors.lastname: Luo
authors.forename: Fuqian
authors.initials: F
authors.lastname: Wang
authors.forename: Jinwen
authors.initials: J
authors.lastname: Zhang
authors.forename: Xingyao
authors.initials: X
authors.lastname: Li
authors.forename: Mengke
authors.initials: M
authors.lastname: Zhang
authors.forename: Xincai
authors.initials: X
authors.lastname: Hao
authors.forename: Yongbo
authors.initials: Y
authors.lastname: Xue
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.forename: F David
authors.initials: FD
authors.lastname: Horgen
authors.forename: Guangmin
authors.initials: G
authors.lastname: Yao
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D047151:Amaryllidaceae Alkaloids / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D018360:Crystallography, X-Ray; D004149:Dioxoles / Q000737:chemistry; D004354:Drug Screening Assays, Antitumor; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006801:Humans; D019668:Liliaceae / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010617:Phenanthridines / Q000737:chemistry
chemical_list: D047151:Amaryllidaceae Alkaloids; D000972:Antineoplastic Agents, Phytogenic; D004149:Dioxoles; D004365:Drugs, Chinese Herbal; D010617:Phenanthridines; C462033:trispheridine; C011361:tazettine; C015330:lycorine