Indole alkaloids from Aspidosperma ramiflorum

Two new bis-indole alkaloids, ramiflorines A and B, were isolated, together with the known compounds, beta-yohimbine and 10-methoxygeissoschizol, from the bark and seeds of Aspidosperma ramiflorum. 2D-NMR analysis, together with CD measurements, established the absolute configuration of both stereogenic centres in the ramiflorines.41396396

Geosteranes: Identification and synthesis of a novel series of 3-substituted steranes

A novel series of 3-alkyl and 3-carboxyalkyl-5 beta(H)-steranes 7-10 along with a full homologous series of carboxyalkyl-sterane (C-1 to C-6) 4-6 with 3 alpha(H)5 alpha(H) configuration have been identified in marine-evaporitic oils from Fazenda Belim, Potiguar Basin (Brazil) on the basis of mass spectral interpretation. The synthesis of enantiomerically pure 3 alpha-alkyl-5 beta(H)-cholestane and 3 beta-alkyl-5 alpha(H)-cholestane standards and their coinjection with petroleum fractions confirmed the structural assignments. (C) 1997 Elsevier Science Ltd.264198478779

PEPTIDE ALKALOIDS OF SCUTIA-BUXIFOLIA

18347347

DIENOIC ACIDS, SYNTHESIS AND C-13 NMR SPECTRAL ANALYSIS

22211512

Composition and biological activity of essential oils from Lippia origanoides HBK

Analyses of the leaf oils from three colletions of Lippia origanoides H.B.K. by GC/MS and H-1- and C-13-NMR showed a similar chemical composition. Carvacrol (33.5-42.9%) was identified as the major component together with gamma-terpinene (8.0-10.5%), thymol (5.1-8.4%), methyl thymol (6.1-8.7%) and p-cymene (11.9-15.8%). In vitro evaluation of the oils showed significant antimicrobial activity against Escherichia coli, Staphylococus aureus, Staphylococus aureus MRSA, Candida albicans and Candida tropicalis.16550450