STRUCTURAL VERSATILITY OF PEPTIDES FROM C-ALPHA,ALPHA-DISUBSTITUTED GLYCINES - SYNTHESIS, CHARACTERIZATION, AND SOLUTION CONFORMATIONAL-ANALYSIS OF HOMOPEPTIDES FROM C-ALPHA-METHYL-C-ALPHA-BENZYLGLYCINE, [(ALPHA-ME)PHE]N(1)

Citation
M. Pantano et al., STRUCTURAL VERSATILITY OF PEPTIDES FROM C-ALPHA,ALPHA-DISUBSTITUTED GLYCINES - SYNTHESIS, CHARACTERIZATION, AND SOLUTION CONFORMATIONAL-ANALYSIS OF HOMOPEPTIDES FROM C-ALPHA-METHYL-C-ALPHA-BENZYLGLYCINE, [(ALPHA-ME)PHE]N(1), Macromolecules, 26(8), 1993, pp. 1980-1984
Citations number
58
Journal title
ISSN journal
00249297
Volume
26
Issue
8
Year of publication
1993
Pages
1980 - 1984
Database
ISI
SICI code
0024-9297(1993)26:8<1980:SVOPFC>2.0.ZU;2-M
Abstract
A complete series of N- and C-blocked, monodispersed homooligopeptides from the sterically hindered (alpha-Me)Phe residue to the pentamer le vel was synthesized step-by-step by solution methods and fully charact erized. The preferred conformation in chloroform solution was determin ed by FT-IR and H-1 NMR as a function of concentration and addition of a perturbing agent. In particular, the results obtained strongly supp ort the view that a series of three consecutive beta-turns (3(10)-heli x) is preferentially adopted by the pentamer, a clear indication that the (alpha-Me)Phe residue is an efficient beta-turn and helix former, much stronger than its unmethylated parent compound (Phe). A compariso n is also made with the conclusions extracted from a published work on homopeptides from Aib, the prototype of C(alpha,alpha)-disubstituted glycines.