Synthesis of the C9-C21 fragment of debromoaplysiatoxin and oscillatoxins A and D

A highly stereoselective synthesis of the C9-C21 fragment of debromoaplysiatoxin and oscillatoxins A and D has been devised. This new approach relies on the cross coupling of titanium enolates from N-acyl-1,3-thiazolidine-2-thiones and dialkyl acetals and the selective hydrogenolysis of O-benzyl protecting groups.

Stereoselective synthesis of the benzyl-protected C9-C21 fragment common to debromoaplysiatoxin and oscillatoxins A and D is disclosed