N-protected amines and their use as prodrugs

Abstract From the Canadian patent

Compounds of formula (I) or (II), wherein X represents H C~1-6? alkyl or C~1-, 6? alkoxy, said alkyl or alkoxy being optionally substituted with one or more groups; a is 0,1,2,3 or 4; Y represents H or C~1-6? alkyl; 1 2 or 3 of the , members Z of the 5-membered aromatic ring are independently selected from -O- -S-, -N= or -NR-, where R is H or C~1-6? alkyl optionally substituted with one or more of groups; and E represents a moiety such that EH is an amine; provided that in formula (I) if a = 0 then Y.noteq.H are provided along with , a method of selecting desired protecting groups by measuring the fragmentation rates of compounds of formula (I) or (II) when the nitro group is selected.