Conformational Studies ofε- CBz-L- Lysine andL- Valine Block Copolypeptides

Stimuli-responsive zwitterionic block copolypeptides: poly(N-isopropylacrylamide)-block-poly(lysine-co-glutamic acid).

Synthesis of novel zwitterionic block copolypeptides, poly(N-isopropylacrylamide)-block-poly(L-glutamic acid-co-L-lysine) [PNiPAM(n)(PLG(x)-co-PLLys(y))m , where n is the number-average degree of polymerization (DP(n)) of PNiPAM block, x and y are the mole fraction of glutamic acid and lysine residues, respectively, and m is the total DP(n) of the peptide block], and their stimuli-responsivenes...

Vibrational spectroscopic studies of L,D-alternating valine peptides

Raman and infrared spectra of Boc-(L-Val-D-Val),-OMe [(LD-Val),], with n = 4, 6 and 8, were obtained in crystalline and solution states. Based on predictions from normal-mode calculations of a number of relevant singleand double-stranded p-helix conformations, structures were assigned for the three oligopeptides under the abovementioned conditions. In the crystalline state, all three oligopepti...

Effect of urea on the optical rotatory dispersion of diketopiperazines of L-serine, L-alanine, L-lysine, L-valine, and L-valylglycine.

Twofold pH and temperature stimuli-responsive behaviour in block copolypeptide-decorated single wall carbon nanotubes.

Temperature- and pH-responsive dispersions of carbon nanotubes in water have been obtained by using di- and tri-block copolypeptides, in which the temperature responsive behaviour is provided by a poly(N-isopropylacrylamide) block, while the pH responsiveness is provided by two different polypeptides with an ampholytic behaviour, poly(L-glutamic acid) and poly(L-lysine). The molecular architect...

A non-planar peptide bond in L-seryl-L-valine.

The molecular structure of (I) is shown in Fig. 1. Bond lengths and angles are normal, but the unusual non-planarity of the peptide bond is quite evident. The associated torsion angle C1ÐC3ÐN2ÐC4 (!) is 157.37 (15) , a deviation from 180 that is superceded among small chiral peptides only by the 156.6 ! angle in N-(tert-butoxycarbonyl)-l-Pro-l-Leu benzyl ester (Sugino et al., 1978). Fig. 2(a) s...