ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
High molecular weight poly(L-valyl-L-valyl-∊-N-benzyloxycarbonyl-L-lysine) (PVVZL) (7) was obtained by condensation in dimethyl sulfoxide of the L-valyl-L-valyl-∊-N-benzyloxycarbonyl-L-lysine p-nitrophenyl ester, synthesized by the DCCStandard abbreviations for amino acid derivatives and peptides are used according to the I.U.P.A.C.-I.U.B. Commission on Biochemical Nomenclature, Biochemistry 11, 1726 (1972). The abbreviations used are: Boc = tert-butyloxycarbonyl; Z = benzyloxycarbonyl; OBzl = benzyl ester; H-Val-OH = valine; H-Lys-OH = lysine; HONp = para-nitrophenol; DDC = dicyclohexylcarbodiimide; DMSO = dimethyl sulfoxide; TFA = trifluoroacetic acid; TFE = 2,2,2-trifluoroethanol; CD = circular dichroism; IR = infrared spectra. method. The conformation of 7 was studied in the solid state and in solution of 2,2,2-trifluoroethanol, acetonitrile-trifluoroethanol and dioxane-trifluoroethanol mixtures by X-ray diffraction method, CD and IR spectroscopy. The results obtained in the solid state suggest the presence of β-structure, whereas in trifluoroethanol solution, at least, a mixture of random coil and β conformation, probably occurs. The aging of the solution seems to give rise to a higher content of β-structure. The addition of acetonitrile and dioxane favours the formation of an increasing amount of β-structure. Therefore, the conformational behaviour of 7 is similar to that of other sequential polypeptides containing valyl residues, which seem to promote the β-structure.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1981.021820221
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