| abstract |
A compound of formula (II): ** Formula ** in which W is selected from H, I and Br; Pg, at each occurrence, is independently selected from an amine protecting group, selected from the group consisting of: 2.7 -di-t-butyl- [9- (10,10-dioxo-10,10,10,10-tetrahydrothioxantyl)] methyloxycarbonyl; 2-trimethylsilylethyloxycarbonyl; 2-phenylethyloxycarbonyl; 1,1-dimethyl-2,2-dibromoethyloxycarbonyl; 1-methyl-1- (4-biphenylyl) ethyl oxycarbonyl; benzyloxycarbonyl; p-nitrobenzyloxycarbonyl; 2- (p-toluenesulfonyl) ethyl oxycarbonyl; m-chloro-p-acyloxybenzyloxycarbonyl; 5-benzoisoxazolylmethyloxycarbonyl; p- (benzyloxycarbonyl) nitroxycarbonyl; ; o-nitrobenzyloxycarbonyl; 3,5-dimethoxybenzyloxycarbonyl; 3,4-dimethoxy-6-nitrobenzyloxycarbonyl; N'-p-toluenesulfonylaminocarbonyl; t-amyloxycarbonyl; p-decyloxybenzyloxycarbonyl; diisopropylmethyloxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; 2,2-dimethoxycarbonyl; Methyloxycarbonyl; 2-furanylmethyloxycarbonyl and tert-butyloxycarbonyl. |