P-Aminobenzyl group

A further noteworthy although not yet exploited blocking is the alkylation of the cysteine side chain with the p-nitrobenzyl group. While it is acid resistant and can not be cleaved by hydrogenolysis, catalytic hydrogenation converts it to the p-aminobenzyl group which is then smoothly removed by salts of divalent mercury, such as Hg acetate ... 

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