Phytochemical Investigation of Woodwardia japonica

The rhizome of Woodwardia japonica Smith (Blechnaceae) is a traditional Chinese medicine, named Gouji Guanzhong in Chinese, to cure flu and verminosis [1,2]. Its clinical use is the same as the rhizome of Dryopteris crassirhizoma, named as Mianma Guanzhong recorded in Chinese pharmacopoeia [3]. Previously, our group reported the isolation of a new trimeric phloroglucinol together with 12 known compounds from the rhizome of Dryopteris crassirhizoma [4]. In this study the phytochemical investigation of the ethanolic extract of W. japonica resulted in the isolation of four sterones, including ecdysterone (1), achyranthesterone A (2), ponasterone A (3), ponasteroside A (4), one triterpene, namely, woodwardic acid (5), and two flavonoids, including kaempferol-3-O-rhamnopyranoside-7-O-rhamnopyranoside (6) and kaempferol-3-O-(4-O-acetyl)-rhamnopyranoside-7-O-rhamnopyranoside (7). Their structures were determined on the basis of UV, 1D, 2D-NMR, MS and reported data. The compounds 1,2,3, and 4 are reported for the first time from this species.

References: [1] Kehai L, Chunjie W (2004) Zhong Yi Yao Xue Kan, 22: 1806–1807. [2] Peigen X (2002) Xin Bian Zhong Yao Zhi, Vol II: 615–617. [3] The Pharmacopoeia Commission of P. R. China. (2010) The Pharmacopoeia of P. R. China, Vol I: 310. [4] Gao Z, Ali Z, et al. (2008) Phytochemistry Letters, 1: 188–190.