Construction of novel 2-screw helices of polypeptides designed with a concept of dipeptide mimics
| Project/Area Number |
16550120
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Functional materials chemistry
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| Research Institution | Chiba University |
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Principal Investigator |
AKAZOME Motohiro Chiba University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (10261934)
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| Project Period (FY) |
2004 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥3,100,000 (Direct Cost: ¥3,100,000)
Fiscal Year 2005: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 2004: ¥2,000,000 (Direct Cost: ¥2,000,000)
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| Keywords | Peptide Chemistry / Supramolecular Chemistry / Dipeptide Mimic / Foldamer / 2-fold Screw Helix / Hydrogen Bondings / 2-Aminophenoxyacetic Acid |
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| Research Abstract |
A foldamer is any functional oligomer that folds into a conformationally ordered state by noncovalent interactions. Natural polypeptides have 3-fold or above helices (α-helix or 3_<10>-helix), but no 2-fold helix. In this research, we focus on the 2-aminophenoxyacetic acids based on the concept of dipeptide mimicking. We found the 2-aminophenoxyacetic acid oligomer construct 2-fold helix by intramolecular hydrogen bonding. These peptidomimetic foldamers will provide a new class of artificial peptides in biochemistry and peptide chemistry.
1.We synthesized 2-nitrophenoxyacetic acid and 2-aminophenoxyacetic acid derivatives and coupled these components to obtain from the dimer to the tetramer.
2.Structure and properties of the novel helix as a foldamer : (1)Induced helicity of these oligomers becomes stronger with increasing chiral units. Single-crystal X-ray analysis of the tetramer revealed 2-fold helical structure in solid state. (2)In cyclohexane, only one C-termial chiral carbon of the tetramer induced strong Cotton effect of the CD spectrum, which suggested the helicity on its whole chain. (3)Polar solvents weaken intramolecular hydrogen bonds to reduce induced CD spectra of the foldamers. However foldamers bearing methyl groups on all α-carbons are almost independent of solvent effects because of folding by steric effects of their α-methyl groups.
3.For the sake of rapid and efficient preparation of oligomers, usual solid phase syntheses of 9-fluorenylmethylcarbamate (FMOC) method was applicable to these foldamers.
4.Structural control of foldamers by intermolecular interactions : The foldamer bearing each carboxyl group of their two benzene rings was synthesized. Two carboxyl groups on the functionalized oligomer interacted with a chiral diamine stereoselectively. Salt forming of the oligomer with (S,S)-cyclohexanediamine stabilized the helical structure in polar solvent. Thus we controlled the folding of the oligomer by intermolecular interactions.
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Report
(3 results)
Research Products
(7 results)
