The 4-azidobenzyloxycarbonyl function; application as a novel protecting group and potential prodrug modification for amines
Abstract
A series of 4-azidobenzylcarbamates [4-N3-C6H4-CH2-O-CO-N(H)-C6H4-X; X = H, Me, MeO, Br, Cl, NO2] have been prepared in good yield, and in high purity, by reaction of 4-azidobenzyl alcohol with the corresponding aryl isocyanate, or by displacement of 4-nitrophenol from 4-azidobenzyl-4-nitrophenylcarbonate by the appropriate amine. The 4-azidobenzylcarbamates were shown to undergo rapid reduction in the presence of dithiothreitol, and the resultant 4-aminobenzylcarbamates underwent immediate cascade degradation to release the target amine. The mild conditions used in this conversion may prove useful in the protection of amines during synthetic procedures or as a possible mode of bioactivation of prodrugs.