Estudo químico da casca do fruto da Pithecoctenium crucigerum (L.) A.H. Gentry (Bignoniaceae)

Abstract

Studies with species of the family Bignoniaceae allowed the isolation of several compounds with therapeutic potential. Pithecoctenium crucigerum (L.) A.H.Gentry, also popularly known as "monkey comb", is a woody vine whose fruit has a dry bark and thick spines. The seeds of this species are used, in some ethnic groups, in the treatment of some diseases such as headaches and neuragia. In this work, a chemical study with the fruit shell of P. crucigerum was developed to investigate and isolate possible bioactive molecules. The extracts were obtained by maceration of the bark: hexane extract (EH), dichloromethane extract (ED), acetate extract (E.A) and hydroalcoholic extract (E. OH). The phytochemical study employed chromatographic techniques to trace a chemical profile, identify, isolate and purify bioactive compounds from the extracts. Phytochemical screening in the extracts (E.H, E.D, E.A and E.OH) indicated the presence of tannins, flavonoids, naphthoquinones, terpenes, steroids, saponins and alkaloids. In the extracts E.H and E.D it was possible to identify fatty acids and terpenes in E.A and E.OH and the methanolic fraction of E.D, with the aid of the GNPS platform, flavonoids, triterpenes, iridoids, saponin, isocoumarin and neolignan were identified. From a fraction from E.A resulted in the isolation and structural elucidation of a flavone, diosmetine and two indole alkaloids, indole-3- carboxaldehyde and indole-3-carboxylic acid. From the E.OH fraction it was possible to isolate and elucidate the martynoside, a glycosylated phenylpropanoid. This study contributed to the knowledge of new substances present in this species.