New guaianolides and xanthine oxidase inhibitory flavonols from ajania fruticulosa

H Li; JC Meng; CH Cheng; T Higa; J Tanaka; RX Tan

doi:10.1021/np990009i

New guaianolides and xanthine oxidase inhibitory flavonols from ajania fruticulosa

J Nat Prod. 1999 Jul;62(7):1053-5. doi: 10.1021/np990009i.

Authors

H Li¹, JC Meng, CH Cheng, T Higa, J Tanaka, RX Tan

Affiliation

¹ State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210093, People's Republic of China, Department of Biochemistry, The Chinese University of Hong Kong, Shatin, N. T., Hong Kong, and Department.

PMID: 10425142
DOI: 10.1021/np990009i

Abstract

Two new guaianolides (1 and 2) were isolated from the aerial parts of Ajania fruticulosa along with a triterpene (alpha-amyrin), two plant sterols (beta-sitosterol and daucosterol), four flavonols [santin (3), axillarin (4), centaureidin, and 5,7,4'-trihydroxy-3, 3'-dimethoxyflavone], and five sesquiterpenes [ketoplenolide B, 9beta-hydroxyeudesma-4,11(13)-dien-12-oic acid, 9beta-acetoxyeudesma-4,11(13)-dien-12-oic acid, 1alpha,4alpha, 10alpha-trihydroxy-9alpha-angeloyloxyguaia-2,11(13)-dien-12, 6alpha-olide, and 3beta,4alpha-dihydroxyguaia-11(13),10(14)-dien-12, 6alpha-olide]. The structures of the new guaianolides were established as 1alpha-hydroperoxy-4beta,8alpha,10alpha, 13-tetrahydroxyguaia-2-en-12,6alpha-olide (1) and 1alpha-hydroperoxy-4alpha, 10alpha-dihydroxy-9alpha-angeloyloxyguaia-2,11(13)-dien-12, 6alpha-olide (2), respectively. Xanthine oxidase assays of all isolates revealed that santin (3) and axillarin (4) inhibited the enzyme with IC(50) values of 36.5 and 36.0 &mgr;M (that of allopurinol used as a positive control in the study was 24.2 &mgr;M), respectively.