New diterpenoids from the aerial parts of Salvia reuterana

The genus Salvia is a valuable origin of structurally diverse terpenoids. In a project directed at structurally interesting bioactive metabolites from Iranian Salvia species, we studied Salvia reuterana. Two new labdane diterpene, 6β,14α-dihydroxy-15-acetoxysclareol (1), and 14α,15- dihydroxy sclareol (2), were isolated from the aerial part of the plant. Their structures were established mainly by 1D and 2D NMR spectroscopic techniques, including 1H-1H COSY, HSQC and HMBC methods and HR-ESI-TOFMS spectral data. Compound 1 and 2 were tested for their inhibitory activity toward HeLa and MCF-7 cell lines. Our results showed that S. reuterana is a rich source of labdane diterpenoids. These compounds are rather rare in Salvia species, although they are frequently found in other genera of the Lamiaceae. S. reuterana is a new source of these diterpenoids.