Home
Resources
Publications
N-alkoxycarbonyl-glutamic and Aspartic Acids. Studies on the Activation and Cyclodehydration and Side-Reaction Encountered in Analysis of Glutamic Acid Using Fmoc-chloride

N-alkoxycarbonyl-glutamic and Aspartic Acids. Studies on the Activation and Cyclodehydration and Side-Reaction Encountered in Analysis of Glutamic Acid Using Fmoc-chloride

F M Chen, N L Benoiton

Int J Pept Protein Res. 1992 Jul;40(1):13-8.

PMID: 1358849

Abstract:

N-Alkoxycarbonylaminodicarboxylic acids were reacted in dichloromethane with N-ethyl-N'-(dimethylaminopropyl)carbodiimide hydrochloride, and with methyl chloroformate in the presence of N-methylmorpholine. Removal of secondary products by washing the mixtures with aqueous solutions gave good yields of the pure crystalline internal anhydrides. Anhydrides of N-benzyloxycarbonyl- (Z) and N-9-fluorenylmethoxycarbonyl-(Fmoc) L-glutamic and L-aspartic acids and of N-tert.-butoxycarbonyl-L-aspartic acid were prepared in this way. The compounds were shown to be amenable to normal phase high-performance liquid chromatography (NP-HPLC) on a CN-column using tert.-butanol-hexane as solvent. The products of the reactions of Z- and Fmoc-glutamic acid with hot acetic anhydride were examined by nuclear magnetic resonance and NP-HPLC before and after methanolysis in an attempt to establish if any of the corresponding pyroglutamates were formed. The reaction of Fmoc-chloride with Fmoc-glutamate was examined for the same reason. It is concluded that the side product generated during the reaction of Fmoc-chloride with glutamic acid which is used for analysis of the latter is the N-protected internal anhydride and not the pyroglutamate as reported in the literature.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP28920436	Fmoc chloride		28920-43-6	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: