86788-46-7Relevant academic research and scientific papers
tert-Butyloxycarbonyl and Benzyloxycarbonyl Amino Acid Fluorides. New, Stable Rapid-Acting Acylating Agents for Peptide Synthesis
Carpino, Louis A.,Mansour, El-Sayed M. E.,Sadat-Aalaee, Dean
, p. 2611 - 2614 (2007/10/02)
A new class of rapid-acting acylating agents, α-BOC and Z amino acid fluorides are obtained as stable, often crystalline, compounds by treatment of the protected amino acid cyanuric fluoride.
Investigation of the Reaction between Amino Acids or Amino Acid Esters and 9-Formylfluorene and Its Equivalents. Possible Utility of the Derived Enamines as Amino Group Protectants
Carpino, Louis A.,Chao, Hann Guang,Tien, Jien-Heh
, p. 4302 - 4313 (2007/10/02)
Treatment of 9-(hydroxymethylene)fluorene/9-formylfluorene (storable as the hemiacetal with methanol, 7) with amino acids and amino acid esters yields the corresponding enamines 8, which may be considered to be hydrocarbon analogues of N-formyl amino acid derivatives.Attempted coupling of the free acids 8 (R'=H) with amino acid esters failed, suggesting insufficient reduction in basicity of the amino group due to the enamine residue.The introduction of electron-withdrawing substituents into the fluorene ring decreases the basicity sufficiently to allow normal peptide coupling reactions, as for example with the 2,7-dichloro analogues derived from 17.Thus phenylalanine derivative 18 treated with leucine methyl ester and DCC gave dipeptide 19.The DC-FM-bar group could be removed by catalytic transfer hydrogenolysis.Mild acid hydrolysis represents a second general deblocking technique for the FM-bar function.It was demonstrated in a model study involving the highly sensitive amino acid α-phenylglycine that the FM-bar protecting group was less prone to cause racemization than the benzyloxycarbonyl function.It was demonstrated that the simple pentapeptide leucine enkephalin 29 could be synthesized using α-DC-FM-bar protection along with tert-butyl-based side chain protecting groups.
