Synthesis of plakevulin A and structure–activity relationships of itsrelatedcompounds against DNA polymerases is described. We have achieved a total synthesis and revised the structure of plakevulin A. Several analogues including untenone A, manzamenone A, and optically active plakevulin A, were prepared and tested with an enzyme inhibition assay for mammalian DNA polymerases. The effect of the methyl
(+/-)-Untenone A, one of the marine cyclopentanoids, has been conveniently synthesized via (+/-)-cis-1-hexadecylcyclopent-2- en-1,4 diol 9 which has been produced from 1-hexadecylcyclopenta-1,3-diene 6 via photo-oxidation and the following reduction. The key step of the present synthesis is the selective alkylation of cyclopenta-1,3-diene to form 6. Optically active (-)- and (+)-untenone A have been prepared from (-)- and (+)-9, respectively, after enzymatic kinetic resolution of (+/-)-9. (C) 2010 Elsevier Ltd. All rights reserved.