Modular Strategies for Structure and Function Employed by Marine Cyanobacteria: Characterization and Synthesis of Pitinoic Acids

Novel bioactive lipids were identified from a Guamanian marine cyanobacterium; the P. aeruginosa quorum sensing inhibitor pitinoic acid A (1) and the anti-inflammatory pitinoic acids B (2) and C (3). 1 is a simple fatty acid which is the major secondary metabolite isolated from this sample. 3 is a chlorinated α-hydroxy fatty acid which appeared to be unstable since purification led to loss of material. Interestingly, 2 is an ester of 1 and 3, but was only isolated in minute amounts. The structure of 2 was confirmed by chemical synthesis which also allowed for biological evaluation. Since the ester 2 is composed of 1 and 3, this compound represents a prodrug strategy to liberate dual biological activity for the management of P. aeruginosa infections and their associated inflammation. Characterization of those lipids and the synthesis of 2 will be presented.