The proposed work involves the development of new amino-protecting groups for use in the synthesis of sensitive, biologically active materials such as peptides, proteins and polynucleotides. Primary attention will be given to groups capable of selective cleavage under mildly basic non-hydrolytic conditions. Model urethanes to be studied include those derived from beta, beta-disulfone alcohols, beta- cyanoethanol and highly fluorinated alcohols. In addition new types of polymeric deblocking agents will be examined.