2,4,5-Trichlorophenyl-(9H-fluoren-9-ylmethoxycarbonylamino)methylcarbamates:Synthesis,isolation,characterization and utility in the synthesis of dipeptidyl ureas

摘要

An efficient synthesis of 2,4,54richlorophenyl-(9H-fluoren-9-ylmethoxycarbonylarnino)methylcarbamates employing isocyanates derived from several Fmoc-amino acids has been described.All the carbamates made have been obtained as crystalline solids and are fully characterized by IR,~1H NMR,~(13)C NMR and mass spectrometry.They have been used as building blocks for the synthesis of several dipeptidyl urea esters.The coupling of carbamates with iV,0-bis[trimethyl-silyl]amino acids resulted in Fmoc-protected dipeptide urea acids in good yield as well as purity.All the dipeptidyl urea esters and acids made have been well characterized.