Passive Membrane Permeability in Cyclic Peptomer Scaffolds Is Robust to Extensive Variation in Side Chain Functionality and Backbone Geometry.
Synthetic and natural cyclic peptides provide a testing ground for studying membrane permeability in nontraditional drug scaffolds. Cyclic peptomers, which incorporate peptide and N-alkylglycine (peptoid) residues, combine the stereochemical and geometric complexity of peptides with the functional group diversity accessible to peptoids. We synthesized cyclic peptomer libraries by split-pool techniques, separately permuting side chain and backbone geometry, and analyzed their membrane permeabilities using the parallel artificial membrane permeability assay. Nearly half of the side chain permutations had permeability coefficients (Papp) > 1 × 10-6cm/s. Some backbone geometries enhanced permeability due to their ability to form more stable intramolecular hydrogen bond networks compared with other scaffolds. These observations suggest that hexameric cyclic peptomers can have good passive permeability even in the context of extensive side chain and backbone variation, and that high permeability can generally be achieved within a relatively wide lipophilicity range.
Department of Chemistry and Biochemistry, University of California, Santa Cruz , 1156 High Street, Santa Cruz, California 95064, United States.|Modality Research Laboratories, Daiichi Sankyo Co., Ltd. , 1-2-58 Hiromachi, Shinagawa-ku, Tokyo 140-8710, Japan.
Akihiro
A
Furukawa
Department of Chemistry and Biochemistry, University of California, Santa Cruz , 1156 High Street, Santa Cruz, California 95064, United States.
Chad E
CE
Townsend
Department of Chemistry and Biochemistry, University of California, Santa Cruz , 1156 High Street, Santa Cruz, California 95064, United States.
Joshua
J
Schwochert
Department of Chemistry and Biochemistry, University of California, Santa Cruz , 1156 High Street, Santa Cruz, California 95064, United States.
Cameron R
CR
Pye
Department of Antibody Discovery & Protein Engineering, Medimmune Ltd. , Cambridge CB21 6GH, United Kingdom.
Maria A
MA
Bednarek
Department of Chemistry and Biochemistry, University of California, Santa Cruz , 1156 High Street, Santa Cruz, California 95064, United States.
R Scott
RS
Lokey
D018938:Caco-2 Cells; D002463:Cell Membrane Permeability / Q000187:drug effects; D006801:Humans; D006860:Hydrogen Bonding; D015394:Molecular Structure; D019151:Peptide Library; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000737:chemistry* / Q000493:pharmacokinetics* / Q000494:pharmacology
D019151:Peptide Library; D010456:Peptides, Cyclic