Systematic strategy for the synthesis of cyanobacterin and its stereoisomers. 1. Asymmetric total synthesis of dechloro-cyanobacterin and its enantiomer.

The stereocontrolled total synthesis of the non-chlorinated analog of cyanobacterin, a potent photosynthesis inhibitor, was achieved by 12 steps in a 10.0% overall yield. Its enantiomer was also synthesized from the same starting material. This synthetic strategy is expected to be applicable to prepare cyanobacterin and all its stereoisomers, together with other similar bioactive compounds.