Glutamic acid dimethyl ester

In some cases, the use of a large excess of alcohol is an option to drive the reaction to completion. Alcoholysis of glutamic acid dimethyl ester derivatives with acylase I was regio- and enantioselective (Figure 6.15). An excess of butanol was used as nucleophile and solvent [62]. 

The methotrexate (MTX) analog (145) is prepared by condensing pyridopyrimidone carboxylic acid (143) with glutamic acid dimethyl ester (144). Testing of amide 145 in vitro against CCRF-CEM leukemia cells revealed that it is... 

Glutamic acid dimethyl ester, L 7.03 0.01 66HP,67HP... 

GME glycine methyl ester GDM glutamic dimethyl ester EDA ethylendiamine GAM glucosamine HDA hexadecylamine BSA bovine serum albumin OVA ovalbumin CA carbonic anhydrase MYO myoglobin H alkaline hydrolysis for converting ester groups from GME or GDM into free carboxylic acid groups that were subsequently activated with EDC for further modifications. 

A different type of modification in Region E was achieved [223, 224] in the form of the MTX analogue (VI.8) and the folic acid analogue (VI. 10), in which NH is inserted between the phenyl and CONH moiety. For the synthesis of (VI.8), 4-amino-4-deoxy-V °-methylpteroic acid was treated with diphenyl-phosphoryl azide in DMSO, the resultant azide ((VI. 12), 87% yield) was photolyzed in DMF solution in the presence of dimethyl L-glutamate to obtain dimethyl ester (VI.9) (51% yield), and (VI.9) was hydrolyzed with 0.1 M... 

Self-catalyzed transesterification with 2-dimethylaminoethanol in DMF has been found effective in cleaving protected peptides from the Mer-rifield resin, in the absence of side-chain benzyl ester protecting groups (Barton et al., 1973). This mild, virtually racemization-free procedure may prove extremely useful for fragment condensation because it yields N-Z-and iV-Boc-protected peptides. Since the reagent, 2-dimethyl-amino-ethanol, specifically cleaves of the benzylic ester group, the benzyl esters of glutamic acid and aspartic acid, if present, will also be hydrolyzed (Barton et al., 1973 Savoie and Barton, 1974). 

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