Eight chemically defined, naturally occurring compounds were extracted from the tropical flora of the Caribbean island of Guadeloupe: pilocarpine, an alkaloid from Pilocarpus racemosus ; heraclenol and isomeranzin, coumarins from Triphasia trifolia; lochnerin, an indole alkaloid from Rauwolfia biauriculata; ibogaine and voacangine, indole alkaloids from Tabernaemontana citrifolia ; texalin, an oxazole from Amyris elemifera; and canellal, a sesquiterpene dialdehyde from Canella winterana. An essential oil fraction from Canella winterana was also tested. The antimycobacterial activity of these substances was tested against Mycobacterium tuberculosis, M. avium and M. kansasii using the Middlebrook 7H11 agar medium, the Bactec 460-TB radiometric methodology, and determination of bacterial viable counts. Three compounds, namely ibogaine, voacangine and texalin, showed antimycobacterial activity. Investigations on the structure-modification and structure-activity relationships of these compounds may help determine new targets for future drug development. z 1998 Federation of European Microbiological Societies. Published by Elsevier Science B.V.

Along with the known alkaloid, O-methylhalfordinol, five known coumarins have been isolated from the leaves oiTriphasia trifolia. The structure of a sixth coumarin, the novel substance 3',-dehydroxy-3''-chlorotriphasiol [10] was determined by the interpretation of spectroscopic parameters.La famille des Rutacées est bien représentée dans les regions tropicales et compre de nombreuses especes utilisées en médecine traditionnelle. Dans les Antilles frangaises, des infusions de feuilles de Triphasia trifolia (Burm. f.) P. Wilson, ou citronnelle á épines, sont utilisées comme vermicide.

No abstract

A new alkaloid, 18-hydroxylochnerine (3), has been obtained from leaves, stem, and root barks of Rauualfia biauriculata. Eight other known alkaloids were also isolated: lochnerine (l), lochvinerine (2), 2 1-hydroxycyclolochnerine (6), vomilenine, perakine, ajmaline, corynanthine, and reserpiline. A tenth alkaloid 0, a yohimbine, has been isolated; the stereochemistry could not be determined, and its exact structure remains unknown.

No abstract