diastereoselective synthesis of 4-vinyl oxazolines syn-2 was developed based on an acid-catalyzed cyclization of bistrichloroacetimidates (E)-1. The reaction likely involves an allyl carbenium ion intermediate in which the adjacent stereocenter directs the stereoselectivity for C–N bond formation. Oxazolines syn-2 were transformed to C-quaternary threoninol, threoninal, and threoninederivatives which can be
evaluation of antiviral activity of new furan-fused tetracyclic compounds are described. The syntheses were satisfactorily achieved on the basis of o-quinodimethane chemistry, using furan-containing benzocyclobutenederivatives as a substrate, in high generality and stereoselectivity. The various derivatives thus synthesized were examined on their inhibitory activity on virus growth using a hemagglutinin