Acylated neo-clerodane type diterpenoids from the aerial parts of Scutellaria coleifolia Levl. (Lamiaceae).

Twenty new neo-clerodane type diterpenoids, scutefolides G1-S (1-20), were isolated from the 70 % aqueous acetone extract of the aerial parts of Scutellaria coleifolia. Their structures were elucidated by extensive spectroscopic analyses. The absolute configurations of 1, 2, 7, 8, 14 and 15 were determined by means of the CD exciton chirality method. Compounds 1, 2, 5, 7, 8, 12, 14, 15, 18 and 19 were evaluated for their cytotoxic activities against four human cancer cell lines, and anti-bacterial activities against methicillin-resistant Staphylococcus aureus.