ABSTRACT
Objective: To study the cembranoid diterpenes from the leaves of Nicotiana tabacum. Methods: The cembranoid diterpenes were isolated and purified by silica gel and preparative HPLC, and their structures were elucidated on the basis of their physicochemistry properties and spectra data. Results: Five cembranoid diterpenes were obtained from the ethanol extract of the leaves of N. tabacum and identified as (1R, 3E, 7E, 10S, 11E)-3,7,11-cembratriene-10, 15-diols (1), (1S, 2E, 4S, 6R, 7E, 10E, 12S)-2, 7, 10- cembratriene-4, 6, 11-triol (2), (1S, 2E, 4R, 6R, 7E, 10E, 12S)-2, 7, 10-cembratriene-4, 6, 11-triol (3), (1S, 2E, 4S, 6R, 7E)-4, 6, 11-trihydroxy- 1-isopropyl-4, 8-dimethylpentadeca-2, 7-dien-12-one (4), and (1S, 2E, 4R, 6R, 7E, 11S, 12S)-11, 12-epoxy-2, 7-cembradiene-4, 6-diol (5). Conclusion: Compound 1 is a new cembranoid diterpene and named as nicotiaditerpene B, and compound 4 is a new natural product.
ABSTRACT
Objective: To study the cembranoid diterpenes from the leaves of Nicotiana tabacum. Methods: The cembranoid diterpenes were isolated and purified by silica gel and preparative HPLC, and their structures were elucidated on the basis of their physicochemistry properties and spectral data. Results: Five cembranoid diterpenes were obtained from the ethanol extract of the leaves of N. tabacum and identified as (1S,2E,4R,6R,7E)-4,6,11-trihydroxy-1-isopropyl-4,8-dimethylpentadeca-2,7-dien-12-one (1), (1S,2E,4R,6R,7E,11E)-2,7,11-cembradiene-4,6-diol (2), (1S,2E,4S,6R,7E,11E)-2,7,11-cembradiene-4,6-diol (3), (1S,2E,4R,6R,7E, 11S)-2,7,12 (20)-cembratriene-4,6,11-triol (4), and (1S,2E,4S,6R,7E,11S)-2,7,12(20)-cembratriene-4,6,11-triol (5). Conclusion: Compound 1 is a new chain-like cembranoid diterpene named nicotiaditerpene A.