Futher Studies on the Steroidal Natural Productsfrom the Formosan Gorgonian Isis hippuris
Several sesquiterpenes isolated from a Formosan gorgonian coral Isis hippuris have shown significant cytotoxic activity against various cancer cell lines. In order to search other active components, we have investigated the chemical constituent of I. hippuris from a Green Island specimen. In the cytotoxcity assay, the EtOAc extract showed potent cytotoxic response toward P-388, A549 and HT-29 cancer cell lines. Thus, the investigation on the chemical content of this extract was carried out.
This study finally led to the isolation of twelve steroids(1-12). Nine metabolites, hippuristerone G (1)¡Bhippuristerone H (2), hippuristerone I (3)¡Bhippuristerone J (4)¡Bhippuristerol E (5)¡B2a,3a-diacetoxy-24-methyl-
11b,18; 18,20b; 22,25-triepoxy-5a-furostane (7)¡B2a,3a-diacetoxy-11b-
furostane (11) and 2a,3a-diacetoxy-11b,18a-dihydroxy-24-methyl-18,
20b; 22,25-diepoxy-5a-furostane (12) are new compounds, whereas hippuristerone A (6), 3a-acetoxy-24-methyl-11b,18; 18,20b; 22,25-
triepoxy-5a-furostane (7) and 3a-acetoxy-11b-hydroxy-24-methyl-22,25-
epoxy-5a-furostan-18,20b-lactone (9) are known compounds. The structures of 1-12 were elucidated by spectroscopic evidences (IR, MS, 1D NMR, 2D NMR) and chemical method. The stereochemistries of compounds 7 and 9 were further confirmed by single-crystal X-ray diffraction analyses. Cytotoxicity test revealed that hippuristerone I (3) exhibited moderate inhibition toward NCI cancer cell line.
Advisor:Yang-Chang Wu; Chung-Nan Lin; Jyh-Horng Sheu
School:National Sun Yat-Sen University
School Location:China - Taiwan
Source Type:Master's Thesis
Keywords:steroid isis hippuris coral cytotoxicity marine natural products gorgonian
Date of Publication:09/01/2002