Isolamento e identificação estrutural de terpenoides de frações enriquecidas do fracionamento cromatográfico do extrato hexânico das cascas da Xylopia calophylla (Annonaceae)

Abstract

The Xylopia genus stands as the second most extensive genus within the Annonaceae family, trailing only Guatteria. Despite its global distribution encompassing approximately 180 species, the comprehension of the chemical composition of its constituent plants remains scant, with fewer than half of its species subjected to analysis. Xylopia calophylla R. E. Fries represents one such species lacking prior literature investigations, rendering the findings of this study novel. Employing classic chromatographic methodologies including column chromatography (CC), analytical thin-layer chromatography (TLC), and preparative thin-layer chromatography (PTLC), seven compounds were successfully isolated and characterized from hexane fractions of X. calophylla bark extract. Of these, five were terpenic compounds designated as XCCLA-11.3, XCCLA-11.4, XCCLA-15.4, XCCLA-16.2, and XCCLA-20.1.4, while two were steroid mixtures identified as XCCLA-14.1 and XCCLA-14.5. Structural elucidation of the compounds relied on analyses encompassing 1H and 13C nuclear magnetic resonance (NMR), mass spectrometry (MS), and gas chromatography/mass spectrometry (GC/MS), revealing the presence of kaurenoic acid, spatulenol, a novel diterpene, ent-15-oxocaur-16-en-19-oic acid, and xylopinic acid, alongside a mixture of stigmast-4-en-3-one, stigmast-4,22-dien-3-one, and campest-4-en-3-one, as well as another mixture comprising β-sitosterol, stigmasterol, and campesterol. While these compounds are previously documented within the Xylopia genus, this study represents the inaugural report of their occurrence in X. calophylla.