title: Pentacyclic triterpenoids from Freziera sp. that inhibit DNA polymerase beta.
abstract: In a survey of crude plant extracts for DNA polymerase 1 inhibitors, a methyl ethyl ketone extract prepared from Freziera sp. exhibited potent inhibition of DNA polymerase beta. Bioassay-guided fractionation of the extract, guided by an assay to detect DNA polymerase beta inhibition, resulted in the isolation of six active pentacyclic triterpenoids (1-6). These triterpenoids had IC50 values ranging from 7.5 to 16 microM in the presence of bovine serum albumin (BSA) and 2.6-5.8 microM in the absence of BSA, consistent with the possibility that these inhibitors may be of use in vivo.
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville 22901, USA.
authors.forename: J Z
authors.initials: JZ
authors.lastname: Deng
authors.forename: S R
authors.initials: SR
authors.lastname: Starck
authors.forename: S M
authors.initials: SM
authors.lastname: Hecht
mesh_terms: D000818:Animals; D001761:Bleomycin / Q000494:pharmacology; D002460:Cell Line; D019951:DNA Polymerase beta / Q000037:antagonists & inhibitors*; D004357:Drug Synergism; D020448:Ericales / Q000737:chemistry*; D015394:Molecular Structure; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D014315:Triterpenes; D001761:Bleomycin; D019951:DNA Polymerase beta