Send to

Choose Destination
J Nat Prod. 2006 Mar;69(3):373-6.

Bioactive isomalabaricane triterpenoids from Rhabdastrella globostellata that stabilize the binding of DNA polymerase beta to DNA.

Author information

Department of Chemistry, M/C 0212, Virginia Polytechnic Institute and State University, Blacksburg, 24061, USA.


Four isomalabaricane triterpenoids were isolated from an extract of the sponge Rhabdastrella globostellata that was active in an assay measuring stabilization of the binding of DNA with DNA polymerase beta. The known compounds stelliferin riboside (1) and 3-epi-29-acetoxystelliferin E (2) were shown to induce 29% and 23% binding, respectively, at 28 microg/mL, while the new compound stellettin J (3) induced 5% binding at 28 microg/mL. The new compound stellettin K (4) had no activity in the binding assay. The compounds were characterized by spectroscopic methods. These compounds displayed varying levels of activity toward the A2780 ovarian cancer cell line, revealing structure-based effects on both the level of cytotoxicity and DNA-polymerase beta binding. This is the first report of natural products with the ability to promote stabilization of the DNA-polymerase beta covalent binary complex.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for American Chemical Society Icon for PubMed Central
Loading ...
Support Center