Cleistanthane diterpenoids from the resin of Vellozia pyrantha A.A.Conc and their chemotaxonomic significance

Abstract

Vellozia pyrantha A.A.Conc. is endemic to the rupestrian fields in northern Chapada Diamantina National Park (Brazil). This species has the peculiar characteristic of only producing flowers after a massive fire event occurs in the surrounding areas. This is the first report on the assessment of the chemical composition of Vellozia pyrantha resin, where five cleistanthane diterpenoids (1–5) were identified. Their structures were proposed after careful analysis of 1H and 13C NMR, DEPT 135, HMBC, HMQC, and COSY spectra as well as comparison with the literature. Cleistanthane diterpenoids show great the potential to be used as chemosystematics biomarkers for the genus Vellozia and, therefore, their chemotaxonomic significance is discussed.