Cryptomoscatones D1 and D2, dihydropyranones isolated from C. mandiocanna, had their stereochemistry
solved after total syntheses and comparison of spectroscopic data of natural and synthetic samples. Natural dihydropyranones
coibacins A and B, metabolites isolated from marine cyanobacterium cf. Oscillatoria sp, which
display antileishmanial activity and anti-inflammatory properties, were synthesized and had their absolute configuration
determined. Our efforts towards the synthesis of cryptomoscatone E3, natural dihydropyranone with unknown
absolute configuration, are also discussed.