Psychotria stachyoides: descobertas químicas e estruturais

• Autor(a) principal: Pimenta, Antônia Torres Ávila
• Data de Publicação: 2009
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/61070
• topic: Psychotria stachyoides; Alcalóides indólicos; Cromatografia; Espectroscopia

In this work we present the phytochemical investigation of stems, leaves and roots of Psychotria stachyoides. The lack of reports on chemical studies with this species led us to this investigation, which brought new data to the chemotaxonomic knowledgement of Psychotria genus. The isolation of six new alkaloids named correantosides A-F corroborated the idea that alkaloids are important chemotaxonomic markers of this genus, and confirmed species of the Heteropsychotria sub-genus as monoterpene indole alkaloids producers. Moreover, the C13 nor-isoprenoid byzantionoside B, the hydroxypyran-2ones tetillapyrone, the triterpenes barbinevic acid and a—amyrine, the quinones alizarin 1-methyl-ether and rubiadine, the coumarin scopoletin and the glycosyl steroids sistosterol and stigmasterol as mixture were isolated. All the isolated compounds are new in the Psychotria genus, with exception of aamyrine and the steroids. The isolation of the chemical constituents were performed by the use of chromatographic techniques, including flash chromatography, thin layer chromatography, preparative chromatography, size exclusion chromatography and preparative high-performance liquid chromatography. The structural characterizations were performed by the use of infrared, mass spectrometry and nuclear magnetic resonance, including one and two-dimensional pulse sequences.