Contribuição ao conhecimento químico de plantas do Nordeste do Brasil: Erythroxylum barbatum O. E. Schulz, Erythroxylum amplifolium (Mart.) O. E. Schulz (Erythroxylaceae) e Croton sonderianus Muell Arg. (Euphoribaceae)

Abstract

This work describes the chemical study of the non volatile constituents of two species of Erythroxylum genus: Erythroxylum barbatum O. E. Schulz and Erythroxylum amplifolium (Mart.) O. E. Schulz (Erythroxylaceae) and the study of the volatile constituents of Croton sonderianus Muell. Arg. (Euphorbiaceae). Phytochemical investigations of the trunk heartwood, stem, roots and leaves of Erythroxylum barbatum yielded fourteen compounds: -sitosterol, -sitosterol and stigmasterol glucosides, devadarool, erythroxytriol Q, erythroxylisin A and erythroxylisin B, procesterol, erythroxydiol X, ent-11-acethoxydevadaran-15 ,16-diol, ent-rosan-1-one-5 -15 ,16-triol, friedelin, stigmast-4-en-3-one, triacontanol and -amyril palmitate. The study of the non volatile constituents of Erythroxylum amplifolium yielded four compounds: -amyril palmitate, quercetin-3-O- -rhamnopyranoside and ethyl linolenate. In addition, the study of the variability of chemotypes of Croton sonderianus specimens from the analyses of volatile constituents of the essential oil from the leaves was accomplished. In this work were identified thirty five constituents and eight chemotypes: CS-A bicyclogermacrene/marmelerin; CS-B bicyclogermacrene/ -phellandrene; CS-C bicyclogermacrene/myrcene; CS-D curzerene; CS-E bicyclogermacrene/ -pinene; CS-F spathulenol/1,8-cineole; CS-G guaiazulene/Z-calamenene; CS-H spathulenol/ -caryophyllene. The structural characterization of the non volatile constituents was made by spectrometric methods as IV, MS, X-ray, NMR 1D and 2D and comparison with the literature data. The volatile constituents were identified by comparing their mass spectra with those of the spectrometer data base using the Wiley L-built library, and two computer library MS search based on their Kovat’s retention indices as a preselection routine, and comparison of the fragmentation pattern with published spectral data.