Three New Pseudodistomins, Piperidine Alkaloids from the Ascidian Pseudodistoma megalarva

Abstract

Bioassay-guided fractionation of the MeOH−CH₂Cl₂ extract of the Micronesian ascidian Pseudodistoma megalarva yielded three new piperidine alkaloids, pseudodistomins D−F (3−5) and the previously reported pseudodistomins B and C (1 and 2). The structure and stereochemistry of these compounds were established by interpretation of spectral data. Pseudodistomins B−F were found to be active in a cell-based assay for DNA damage induction, but the activity was due to an alternative mechanism.