(S)-β3-Homolysine- and (S)-β3-Homoserine-Containing β-Peptides: CD Spectra in Aqueous Solution

✍ Scribed by Stefan Abele; Gilles Guichard; Dieter Seebach

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: German
• Weight: 287 KB
• Volume: 81
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/(sici)1522-2675(19981216)81:12<2141::aid-hlca2141>3.0.co;2-5

✦ Synopsis

For further structural studies and for physiological investigations of b-peptides, it is necessary to have H 2 Osoluble derivatives. Thus, we have prepared b-hexa-, b-hepta-, and b-nonapeptides (1 ± 6) with two, three, and seven side chains of lysine and serine. To detect possible p-p interactions, we also included the b-amino acid b 2 -HHop, resulting from homologation of so-called homophenylalanine (Hop) (5 and 6). The Fmoc-b 2 -and b 3amino-acid derivatives (11 ± 14 and 19), and the corresponding b-peptides were prepared by methods previously described (solid-phase peptide coupling; HPLC-pure samples, Fig. 1). Circular-dichroism spectra (Fig. 2) indicate the presence of less pronounced secondary structures (especially of the lysine analogues with multiple positive charge) in H 2 O as compared to MeOH. The b 3 -heptapeptide (3) with two serine side chains is well soluble in H 2 O and exhibits the CD pattern typical of the 3 1 -helical structure.