Carboxybenzyl or benzyloxycarbonyl or Cbz or Z (in honor of discoverer Leonidas Zervas) is an amine protecting group in organic chemistry. The protected amine can be deprotected by catalytic hydrogenation or treatment with HBr, yielding a terminal carbamic acid that then readily decarboxylates to yield the free amine. Commonly used for oligopeptide synthesis introduced by Max Bergmann in 1932. Building block for some inhibitors of enzymes