Toward the stereochemical assignment of euvesperins A and B: total synthesis of the possible structures of the natural products.

The possible structures of euvesperins A and B were synthesized. The results of our synthesis suggest that euvesperin A may be a mixture of the (2 R ,3 R ,4 S ,7 S ) and (2 S ,3 S ,4 R ,7 S ) isomers and euvesperin B may be a mixture of the (2 R ,3 S ,4 S ,7 S ) and (2 S ,3 R ,4 R ,7 S ) isomers in consideration of their putative biosynthetic pathways.