Largely as a result of the work of Ragnarsson and associates, 2 protected NJV-bis (B0C) a- amino acids, potentially important synthetic intermediates which incorporate urethane protection of both available a-NH bonds, have routinely become available. It was pointed out that such double protection, precluding oxazolone formation, could be advantageous with regard to potential racemization problems. On the other hand, the presence of a second ...
