New labdane diterpenoids from Hyptis fasciculata

Two new labdane diterpenoids, 15 beta-methoxyfaciculatin (1) and 15 alpha-methoxyfaciculatin B (2), together with the previously known methoxynepetaefolin (3), were isolated from a methanol extract of the dried aerial parts of a Brazilian medicinal plant, Hyptis faciculata. Their structures were elucidated by analysis of spectroscopic data. Plausible biogenetic correlation between faciculatins and nepetaefolin is briefly discussed.