Search

Sulfonamide-containing tetronic acids 1 , structural analogues of the HIV-1 protease inhibitor tipranavir, were synthesised in five steps including a microwave-assisted Claisen rearrangement of cinnamyl tetronates and a modified Charette cyclopropanation of the so-formed 3-allyltetronic acids. Compounds 1 with two non-H residues (R 1 , R 2 ) at C-5 of the tetronate core exhibited structure-dependent antiviral activity in two HIV strains. Derivatives 1c (R 1 =R 2 =Me, R 3 =Cl) and 1d (R 1,2 =(CH 2 ) 5 , R 3 =Me) were most active (IC 50 NL4-3 .

The synthesis of the marine natural products zonarone and isozonarone was achieved via (+)-albicanic acid, a sesquiterpene of the drimane type. Coupling of the appropiate drimane-synthon with lithiated hydroquinone ethers led to sesquiterpene arenes, which were further modified to the target molecules. Stereoselective epoxidation followed by regioselective opening of the oxirane ring yielded yahazunol.