title: Synthesis of a novel macrocyclic library: discovery of an IGF-1R inhibitor.
abstract: We present a new approach for the conversion of active sequences of proteins and peptides into small molecules. A library of macrocyclic disulfide molecules was made, in which the active pharmacophores of the parent peptide are preserved while the size of the macromolecular scaffold on which the pharmacophores are arranged is varied. This enables a systematic search for macromolecules in which the pharmacophores are in an appropriate conformation for biological activity. We developed two procedures for the synthesis of such libraries from building blocks that include commercial amino acids and functionalized aldehydes. Chemical synthesis using the "tea-bag" method gave a library with higher diversity, but low yields, compared to the manual synthesis of the library, in which the compounds were synthesized in individual vessels and the yield and purity improved dramatically. As a proof of concept, we synthesized a 34-member library derived from the sequence of the activation loop of insulin-like growth factor-1 receptor. Selected compounds were screened, and one was found to be biologically active in the low micromolar range. The concept presented here may prove particularly useful in cases where the pharmacophores are known but need to be systematically screened for a spatial arrangement that will enable biological activity.
authors.affiliation: Department of Organic Chemistry, The Fritz Haber Research Center, Jerusalem 91904, Israel.
authors.forename: Nir
authors.initials: N
authors.lastname: Qvit
authors.forename: Hadas
authors.initials: H
authors.lastname: Reuveni
authors.forename: Sharon
authors.initials: S
authors.lastname: Gazal
authors.forename: Adi
authors.initials: A
authors.lastname: Zundelevich
authors.forename: Galia
authors.initials: G
authors.lastname: Blum
authors.forename: Masha Y
authors.initials: MY
authors.lastname: Niv
authors.forename: Alexandra
authors.initials: A
authors.lastname: Feldstein
authors.forename: Sharon
authors.initials: S
authors.lastname: Meushar
authors.forename: Deborah E
authors.initials: DE
authors.lastname: Shalev
authors.forename: Assaf
authors.initials: A
authors.lastname: Friedler
authors.forename: Chaim
authors.initials: C
authors.lastname: Gilon
mesh_terms: D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D047028:Macrocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D017526:Receptor, IGF Type 1 / Q000037:antagonists & inhibitors*
chemical_list: D047028:Macrocyclic Compounds; D017526:Receptor, IGF Type 1