Evidence for the rapid conversion of stephacidin B into the electrophilic monomer avrainvillamide in cell culture.

J Am Chem Soc

Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.

Published: April 2007

We report that the dimeric alkaloid stephacidin B () and the monomeric alkaloid avrainvillamide () function equivalently within experimental error to inhibit the growth of four different cultured human cancer cell lines. We also show that the proportion of the monomer greatly outweighs that of the dimer in the medium of incubation, and that the half-life for the transformation of to is short relative to the half-life of cell division. Finally, using a monomer-based affinity reagent, we provide evidence that the monomer () interacts with intracellular thiol-containing proteins, likely by covalent modification.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3175819PMC
http://dx.doi.org/10.1021/ja0690971DOI Listing

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