A PHOTOLABILE PROTECTING GROUP FOR THE PHENOLIC HYDROXYL FUNCTION OF TYROSINE

Abstract
The o-nitrobenzyl group (ONBzl) was utilized to protect the phenolic function of the side chain of tyrosine. Optimal conditions for its mild photolytic removal were established. The preparation and properties of some (O-ONBzl)-tyrosine derivatives of potential value in the synthesis of tyrosine-containing peptides are described. Their use in the synthesis of the dipeptide, N-benzyloxycarbonyl-L-tyrosyl-glycine ethyl ester, is presented as an example.