Conformations of oligoprolines with different configurational sequences and their association complexes with alkali and alkali-earth ions

✍ Scribed by Pasquale De Santis; Antonio Palleschi; Anita Scipioni; Mercedes Camalli; Riccardo Spagna; Giancarlo Zanotti

• Publisher: Wiley (John Wiley & Sons)
• Year: 1998
• Tongue: English
• Weight: 261 KB
• Volume: 45
• Category: Article
• ISSN: 0006-3525
• DOI: 10.1002/(sici)1097-0282(199803)45:3<257::aid-bip8>3.0.co;2-q

✦ Synopsis

To clarify the possible molecular mechanism of cation unit conductance of poly(D,Lproline) across lipidic membranes, the structure and conformation of tetraproline derivatives with different configurational sequences in solid state, as well as in solution and in the presence of alkali and alkali-earth ions, were investigated using x-ray analysis, CD, and nmr spectroscopy. The tetraproline derivatives Boc(D-Pro-L-Pro-L-Pro-D-Pro)OBg and Boc(L-Pro) 4 OBg show very different conformational versatilities in solutions as well as different propensities to form complexes with Ca 2/ ion. This is interpreted, based on previous evidence, as due to different abilities to form ion complexing cavities.