Neo- and seco-neo-clerodane diterpenoids from Teucrium gracile and T. Fruticans - Bruno, M.; Alcazar, R.; de la Torre, M.C.; Piozzi, F.; Rodriguez, B.; Savona, G.; Perales, A.; Arnold, N.A. (Elsevier)
Two new neo-clerodane diterpenoids, teugracilins D and E, together with the previously known diterpene 19-acetylteulepicin, have been isolated from Teucrium gracile. The structures of teugracilin D [19-acetoxy-40α, 18;15,16-diepoxy-3β,6α-dihydroxy-neo-cleroda-13(16),14-diene-(20-O-acetyl) -20R, 12S-hemiacetal] and teugracilin E [3β,6α,12ξ,19,20-pentaacetoxy-4α,18;15,16-diepoxy-neo-cleroda-13(16),14- diene] were determined on spectroscopic grounds. In addition, reexamination of the diterpene composition of T. fruticans allowed the isolation, for the first time from Teucrium species, of a new seco-neo-clerodane derivative, fruticolide. Its structure, 19-acetoxy-4α,18;15,16-diepoxy-5,6-seco-neo-cleroda-13(16),14-dien-6,1α-ol ide, was established by spectroscopic means, including an X-ray diffraction analysis.
http://linkinghub.elsevier.com/retrieve/pii/0031-9422(92)83722-B
Keywords: W; V