KINETIC AND THERMODYNAMIC ATROPDIASTEREOSELECTION IN THE SYNTHESIS OF THE M(5-7) TRIPEPTIDE PORTION OF VANCOMYCIN

The C(alpha) stereochemistry of the position-5 arylglycine plays a pivotal role in determining the kinetic atropdiastereoselection in the oxidative biaryl cyclization reaction, the key step in a biomimetic strategy directed toward the synthesis of the M(5-7) vancomycin fragment. The equilibrium ratio of biaryl and amide conformations within this 12-membered macrocycle is significantly influenced by interaction of this same center with adjacent substituents.