1. Biologically active vallesamine, strychnan, and rhazinilam alkaloids from Alstonia: Pneumatophorine, a nor-secovallesamine with unusual incorporation of a 3-ethylpyridine moiety.
- Author
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Lim JL, Sim KS, Yong KT, Loong BJ, Ting KN, Lim SH, Low YY, and Kam TS
- Subjects
- Aldehydes chemistry, Aldehydes pharmacology, Animals, Antineoplastic Agents, Phytogenic chemistry, Antineoplastic Agents, Phytogenic pharmacology, Aorta drug effects, Carbazoles chemistry, Carbazoles pharmacology, Cell Line, Tumor drug effects, Crystallography, X-Ray, Drug Evaluation, Preclinical methods, Heterocyclic Compounds, 4 or More Rings chemistry, Heterocyclic Compounds, 4 or More Rings pharmacology, Humans, Indole Alkaloids pharmacology, Indolizines chemistry, Indolizines pharmacology, Lactams chemistry, Lactams pharmacology, Molecular Structure, Phenylephrine pharmacology, Pyrans chemistry, Pyrans pharmacology, Pyridines chemistry, Pyridines pharmacology, Rats, Secologanin Tryptamine Alkaloids chemistry, Secologanin Tryptamine Alkaloids pharmacology, Vasodilator Agents chemistry, Vasodilator Agents pharmacology, Alkaloids chemistry, Alkaloids pharmacology, Alstonia chemistry, Indole Alkaloids chemistry
- Abstract
Four alkaloids comprising two vallesamine, one strychnan, and one pyranopyridine alkaloid, in addition to 32 other known alkaloids were isolated from two Malayan Alstonia species, Alstonia pneumatophora and Alstonia rostrata. The structures of these alkaloids were determined using NMR and MS analyses, and in one instance, confirmed by X-ray diffraction analysis. The nor-6,7-secovallesamine alkaloid, pneumatophorine, is notable for an unusual incorporation of a 3-ethylpyridine moiety in a monoterpenoid indole. The rhazinilam-type alkaloids (rhazinicine, nor-rhazinicine, rhazinal, and rhazinilam) showed strong cytotoxicity toward human KB, HCT-116, MDA-MB-231, and MRC-5 cells, while pneumatophorine, the uleine alkaloid undulifoline, and the strychnan alkaloids, N4-demethylalstogustine and echitamidine, induced concentration dependent relaxation in phenylephrine-precontracted rat aortic rings., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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