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 phenolic acids from the aerial part of Clerodendranthus spicatus. METHODS: The phenolic acids were isolated from the aqueous extract of C. spicatus by various chromatographic methods, and their structures were elucida-ted on the basis of their physicochemistry properties and spectral data. RESULTS: A new phenolic acid possess a unique bicycle [2.2.2] octane skeleton was obtained from the aqueous extract of the aerial part of C. spicatus. CONCLUSION: Compound 1 is a new phenolic acid and named cleroden E.
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.
ABSTRACT
Rhubarb is a perennial herb belonging to the genus Rheum L. (Polygonaceae). Rhei Radix et Rhizoma (rhubarb roots and rhizomes) is one of the most popular Chinese materia medica and has been widely used for strong laxative function. About 200 compounds with six different types of skeletons (anthraquinone, anthrone, stilbene, flavonoids, acylglucoside, and pyrone) have so far been isolated from eighteen species of the genus Rheum L. These constituents showed extensive pharmacological activities including cathartic, diuretic, anticancer, hepatoprotective, anti-inflammatory, and analgesic effects, as well as toxicological effects. Chemical fingerprint, LC-MS, and other analytical techniques have been used for the quality control of rhubarb. This comprehensive review summarizes the researches into the isolation, pharmacological activities, and phytochemical analysis reported since investigations began in the late 1940s. In addition, pharmacokinetic studies and clinical application of rhubarb are also discussed in present paper. © 2013 Tianjin Press of Chinese Herbal Medicines.