Poly-y-ethyl-L-glutamate

Poly-y-ethyl-L-glutamate CDCI3, CD2C12 Chiral 98,99... 

FIGURE 9.21. Structures of imidazole-modified poly(y-ethyl L-glutamate) and deuteroporphyrin-IX-Fe tl used by Grimshaw and Trocha-Grimshaw to construct an analog of cytochrome c (see Ref. 143). 

Poly(y-ethyl-L-glutamate) 1,2-dichloroethane dichloroacetic acid AsoI- B sol- B 303 K 303 K 1968GIA 1968G1A... 

Chen, G.W., Hayashi, T, and Nakajima, A. (1981) Synthesis and molecular characterization of A-B-A tri-block copolymers composed of poly(Y-ethyl L-glutamate) as the A component and polybutadiene as the B component. Polymer Journal, 13,433-442. 

The most common chiral liquid crystal that has been employed for NMR discrimination is polyf-y-benzyl-L-glutamate) (PBLG), although poly(7-ethyl-L-glutamate) (PELG) and poly-s-carbobenzyloxy-L-lysine (PCBLL) have been used as well. The liquid crystal is dissolved in a co-solvent such as methylene chloride, chloroform, or dimethylformamide. The co-solvent is chosen to facilitate dissolution of the substrate. 

FIG. 4.6 Chemical structures of po(y-(S- 2- 4-(4-((decyloxy)phenyl)a2o)phenoxy)ethyl)-L-glutamate), denoted by P2.10, and poly-(S-(2-(4- 4- (hexylphenylaio)phenoxy)ethyl)-L-glutamate) and poly- 5-(6-(4- 4-((hexylphenylaio)phenoxy)ethyl)-L-glutamate), denoted by Pj j and P4 4, respectively. 

L-aspartate (7), y-[2-(9-carbazoIyl)ethyl]-L-glutamate(8), N -[(9-carbazolyl)-carbonyl]-L-lysine (9), and 2-[(9-carbazolyI)ethyl]-L-cysteine (10). No detailed information on the optical rotatory properties of the indicated polymers has been reported, whereas a great deal of attention has been focused on the dichroic absorption properties especially for different samples of poly(8). While the first three polymers are characterized by an a-helix structure in both solution and solid state, poly(lO) may assume antiparallel pleated-sheet and normal antiparallel P-forms. Apparently, the presence of the bulky side group does not substantially affect the conformational structure imposed by the polypeptide backbone. Additionally in concentrated solutions, the cholesterogenic propensity of polypeptides such as those based on L-glutamic acid, L-aspartic acid, and L-lysine is not appreciably influenced by the steric and electronic characteristics of the carbazole moiety anchored via different spacers to the peptide units. 

Several poly(a-amino acids) with pendant carbazole groups have been described. Tanikawa et al. [193] reported on the synthesis of poly(y-2-(V-carbazolyl)-ethyl-L-glutamate) (18a) and discussed the photoconductivity of the polymer and its charge-transfer complex with TNF. The photocurrents in (18a) are about one order of magnitude smaller than in PVK at all measured wavelengths. Poly(5 -2-(V-carbazoly-l)ethyl-L-cysteine) [194,195] (18b) a jS-sheet forming polypeptide, was synthesized from the corresponding V-carboxy anhydride. 

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