Various processes for producing .alpha.-APM are known, for example a process which comprisesreacting N-protected L-aspartic anhydride with L-phenylalanine methyl ester (U.S. Pat. No. 3,786,039), a process which comprises reacting N-protected L-aspartic anhydride with L-phenylalanine (U.S. Pat. No. 4,173,562), and a process which comprisescondensing N-benzyloxycarbonyl-L-aspartic acid and L-phenyla