Template fixed beta-hairpin loop mimetics and their use in phage display

A method of screening for template-fixed hairpin beta-mimetics having a template that conformationally stabilizes a beta-hairpin and which is capable of binding to a specific binding partner, comprising the steps of

• a) providing a library of template-fixed beta-hairpin mimetics;
• b) contacting the library of step a) with the binding partner;
• c) selecting from the library peptides capable of forming a non-covalent complex with the binding partner;
• and
• d) optionally isolating the peptides or determining their sequence by DNA-analysis, wherein the library of template-fixed beta-hairpin mimetics comprises compounds of the general formula
• R1-Cys-Z-Cys-R2 (I),
• in which
• the two Cys residues form a disulfide bridge,
• R1 and R2 comprise Glu-Thr and Thr-Lys;
• or Lys-Thr and Thr-Glu;
• or Thr-Glu and Lys-Thr;
• or Thr-Lys and Glu-Thr;
• or Leu-Glu and Lys-Val;
• or Val-Lys and Glu-Leu;
• or Glu-Leu and Val-Lys;
• or Lys-Leu and Val-Glu;
• or Glu-Leu-Lys and Glu-Val-Lys;
• or Lys-Val-Glu and Lys-Leu-Glu;
• or Leu-Glu-Lys and Glu-Lys-Val;
• or Val-Lys-Glu and Lys-Glu-Leu;
• or Glu-Lys-Leu and Val-Glu-Lys;
• or Lys-Glu-Val and Leu-Lys-Glu;
• or Lys-Glu-Leu and Val-Lys-Glu;
• or Glu-Lys-Val and Leu-Glu-Lys, and
• Z is -Lys-Trp-Phe-Ser-Asn-His-Tyr-Gln-[SEQ ID NO:23];
• or -Phe-Leu-Ala-His-Tyr-Ala-[SEQ ID NO:24].