title: The influence of molecular conformation upon the self-assembly of cyclohexane diamide diacids.
abstract: BACKGROUND
  Information regarding the self-association of small peptide motifs can be used in the design of peptide microstructures. Previous work in our laboratories illustrated the self-association of certain diamide diacids into microcapsules. In this report a series of cyclohexane diamide diacids are investigated. The cyclohexylene (R-C6H10-R) system (with its axial and equatorial requirements) provided an opportunity to study the influence of molecular conformation upon the self-aggregation process.
  
  
  RESULTS
  Condensation of the respective cis- and trans-1,2-, 1,3-, and 1,4- cyclohexane dicarboxylic acid platforms with two equivalents of a L-Phe ester followed by deprotection gave the desired diamide diacids. Basic solutions of cis-1,2-, trans-1,3-, and cis-1,4-diamide diacids generated solid microspheres when acidified to pH 2.4. Molecular modeling revealed that 1,3-diaxial interactions favor a helical turn within these diamides.
  
  
  CONCLUSIONS
  Access to 'complementary' molecular geometries is needed to self-associate into microscopic architectures.
authors.affiliation: Department of Medicinal Chemistry, University of Florida, J. Hillis Miller Health Center, Gainesville 32610, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Bergeron
authors.forename: G W
authors.initials: GW
authors.lastname: Yao
authors.forename: G W
authors.initials: GW
authors.lastname: Erdos
authors.forename: S
authors.initials: S
authors.lastname: Milstein
authors.forename: F
authors.initials: F
authors.lastname: Gao
authors.forename: J
authors.initials: J
authors.lastname: Rocca
authors.forename: W R
authors.initials: WR
authors.lastname: Weimar
authors.forename: H L
authors.initials: HL
authors.lastname: Price
authors.forename: O
authors.initials: O
authors.lastname: Phanstiel
mesh_terms: D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry*; D002214:Capsules / Q000138:chemical synthesis; D003510:Cyclohexanes / Q000737:chemistry*; D003998:Dicarboxylic Acids / Q000737:chemistry*; D015195:Drug Design; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D011487:Protein Conformation; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000577:Amides; D002214:Capsules; D003510:Cyclohexanes; D003998:Dicarboxylic Acids