Acylated neo-clerodanes and 19-nor-neo-clerodanes from the aerial parts of Scutellaria coleifolia (Lamiaceae)

Scutefolides A(1) and A(2), two acylated neo-clerodanes with a 19,18-gamma-lactone, scutefolides B-1, B-2 and C, three 19-nor-neo-clerodanes, together with scutefolides D, E-1, E-2 and F, four neo-clerodanes, were isolated from the EtOAc-soluble fraction of the aerial parts of Scutellaria coleifolia. Their structures were established on the basis of spectroscopic analysis. The absolute configurations of four of these compounds were elucidated by the CD exciton chirality method. Cytotoxic activities of scutefolides D-F against four cancer cell lines (KB, A549, HeLa, and MCF7) were also evaluated, but they were inactive. (C) 2015 Elsevier Ltd. All rights reserved.