New Labdane Diterpenes from Leonurus cardiaca

Leonurus cardiaca L. has been used in traditional medicine against nervous and functional cardiac disorders since 15th century and described for producing sedative, hypotensive and cardiotonic pharmacological effects [1,2]. The plant has been reported to have furanic labdane diterpenes [3], Sterols [4], Iridoids [5] and Alkaloids [6] etc. The ethanolic extract of leaves of Leonurus cardiaca yielded three new labdane type diterpenes, 15-ethyl-leopersine C (1), 15-methyl-leopersine C (2) and 15-methyl-epi-leopersine C (3). The structures were determined using 1D- and 2D-NMR, IR, UV, HR-MS. The absolute stereochemistry of compounds 1 – 3 were assigned with the help of a ROESY experiment. Acknowledgements: This work was supported in part by the United States Department of Agriculture, Agricultural Research Service, Specific Cooperative Agreement No 58-6408-2-0009 and Grant Number P20RR021929 from the National Center For Research Resources. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center for Research Resources or the National Institutes of Health. References: [1] British Herbal Pharmacopoeia Compendium. (1990) BHMA Megaron Press, Bournemouth 1: 161. [2] Russian Pharmacopoeia. (1968) Gosudarstwiennaja Farmakopea SSSR (X), Moskwa M, p.347–348. [3] Knoess W, Zapp J (1998) Planta Medica, 64: 357–361. [4] Senatore F, et al. (1991), Herba Polonica, 37: 3–7. [5] Guisso M, et al. (1974), Gazzetta Chimica Italiana, 104: 25–33. [6] Gulubov AZ, Chervenkova VB (1970) Biologiya, 8: 129–132.