Search for Secondary Metabolites in the Species Erythroxylum rimosum O. E. Schulz

Erythroxylum rimosum O. E. Schulz is a species restricted to the Northeast region of Brazil, occurring in Restinga, Cerrado and Carrasco vegetation. Previous research on the crude ethanolic extract of the leaves of E. rimosum, reported the identification of pentacyclic triterpenes, steroids, tropanic alkaloids and flavonoids. In studies carried out in world databases, few phytochemical studies were found for this species, so we consider it as a source of natural resources to be explored. Thus, a phytochemical study of its crude ethanolic extract (BSE) was carried out. The botanical material was collected in the municipality of Pirambu, state of Sergipe. It was then oven dried (40 C), triturated and macerated with 95 % EtOH. The BSE (105 g) was dissolved in a methanol:water (7:3) solution and partitioned with the solvents: hexane (Hex), dichloromethane (DCM) and ethyl acetate (AcOEt). The DCM phase was submitted to column chromatography, using silica gel as stationary phase and as mobile phase, and the solvents Hex, AcOEt and MeOH, pure and in binary mixtures white the increase of the polarity orders. There were obtained 55 fractions which were pooled according to their respective retention factors (Rfs) by analytical thin-layer chromatography (CCDA). Fraction 30-43 and fraction 53-55 were encoded as Er-1 and Er-2, respectively. These substances had their structures identified by one and two dimensional NMR spectroscopy. After comparison of NMR data with those reported in literature the compounds were identified, for the first time in this species, as quercetin-3-O--L-rhamnoside (Er-1) and cys-4-hydroxy-1-methyl-2pyrrolidine carboxylic acid (Er-2).