A convergent synthesis of (4R,15R,16R,21S)-rollicosin (1) and (4R,15S,16S,21S)-rollicosin (2) was accomplished. Hydroxy lactone 6a and/or 6b were synthesized from 4-pentyn-1-ol, and α,β-unsaturated lactone 7 was synthesized from γ-lactone 8 and 5-hexen-1-ol. Inhibitory activity of these compounds was examined with bovine heart mitochondrial complex I.
Squamostolide and its related analogs were designed and synthesized for biological evaluation. All these compounds were tested for growth inhibition activities against human tumor cell lines, in which one of the compounds showed the most potent cyto-toxicity among these derivatives against a full panel of 60 human cancer cell lines. The same compound also showed G2/M phase arrest and a weak apoptotic effect during flow cytometric analysis. (c) 2005 Elsevier Ltd. All rights reserved.