Carbobenzoxy-glutamic acid

An enzyme (cathepsin) hydrolyzes L-glutamyl-L-tyrosine to carbobenzoxy-L-glutamic acid and L-tyrosine. It has been found (Frantz and Stephenson,/. Biol. Chem., 169,359,1947) that the glutamic acid formed in the hydrolysis, inhibits (competitively) the progress of the reaction by forming a complex with cathepsin. The course of the reaction is followed by adding tyrosme decarboxylase which evolves C02. 

BG SG SC SL BCK SCK BK SK BE SE Polybutadiene-poly(benzyl-L-glutamate) Polystyrene-poly (benzyl-L-glutamate) Polystyrene-poly(cinnamyl-L-glutamate) Polystyrene-poly(L-leucine) Polybutadiene-poly(carbobenzoxy-L-lysine) Polystyrene-poly(carbobenzoxy-L-lysine) PoIybutadiene-poly(L-lysine) Polystyrene-poly(L-Iysine) Polybutadiene-poly(L-glutamic acid) Polystyrene-poly(L-glutamic acid)... 

N-Carboxy- from N Carbobenzoxy-L-glutamic acid anhydrides s. 19, 209 NCOOCH CeHs NCOOH... 

Garboxy-2-pyrrolidon es from carbobenzoxy-L-glutamic acid 1,5-anhydrides ... 

Fig. 15. Effect of pH on the hydrolysiB of four substrates by crystalline papain in the presence of 0.005 M cysteine and 0.001 M Versene (100). The substrates were carbobenzoxy-L-leucinamide (CLA), hippurylamide (HA), carbobenzoxy-i/-glutamic acid diamide (CGDA), and carbobenzoxy-L-isoglutamine (CIG).

Fig. 23. InHueiice of pH on tlie inhibition of hydrolysis of benzoyl-i arginin-ainide by 0.01 M and 0.02 M carbobenzoxy-i>-glutamic acid (159). The extent of inhibition was determined by the effect on initial velocity of hydrolysis of 0.025 M BAA. The reaction mixtures contained 0.04 M acetate buffer, 0.01 M BAL, and 0.1 M KCl.

In (Section 8) we have considered kinetic phenomena encountered during the copolymerization of L- and D-enantiomorphs of a single type of NCA. Copolymerization of mixtures of NCAs of different a-amino acids to give random copolymers is readily realizable [2], one of the earliest examples reported being the synthesis of a DL-phenylalanine L-leucine copolymer by Woodward and Schramm [78]. However, there are few reports on the kinetics of random copolymerization. Shalitin and Katchalski [79] studied the copolymerization of the NCAs of 7-benzyl L-glutamate (A) and e,N-carbobenzoxy L-lysine (B) initiated by diethyl-amine in N,iV-dimethylformamide at 25°C and obtained the interesting result that the over-all rate of reaction (measured by the CO2 evolution) is equal to the sum of the rates of reaction of the individual monomers under similar conditions. The copolymerization is represented schematically in (60)... 

Synthesis. Using hexamethyl amine as initiator, we have copolymerized, in DNF solution, the N-carboxy-anhydride [NCA] of benzyl -L-glutamate with the NCAs of the following amino acids cinnamyl-L-glutamate, carbobenzoxy-L-lysine, L-leucine, dL-phenyl alanin, L-phenyl alanin. 

N-Carbobenzoxy-L-glutamic anhydride hydrogenated with 10%-Pd-on-charcoal in dioxane under strictly anhydrous conditions until H -uptake ceases N-carboxy-L-glutamic anhydride (Y 83 ) treated with water whereupon violent COg-evolution takes place L-pyroglutamic acid (Y 79%). J. Kovacs, H. N. Kovacs, and R. Ballina, Am. Soc. S5, 1839 (1963). 

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