| Project/Area Number |
17550127
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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 | Nagoya Institute of Technology |
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Principal Investigator |
YAMAMURA Hastuo Nagoya Institute of Technology, GRADUATE SCHOOL OF ENGINEERING, ASSOCIATE PROFESSOR (80220440)
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| Project Period (FY) |
2005 – 2006
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| Project Status |
Completed (Fiscal Year 2006)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2006: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2005: ¥3,100,000 (Direct Cost: ¥3,100,000)
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| Keywords | titration calorimetry / chiral recoenition / cyclodextrin / 高分解能NMR |
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| Research Abstract |
Complex stability constant, standard free energy (△G^O), reaction enthalpy (△H^O), and entropy change (T△S^O) for 1:1 inclusion complexation of the chiral amino acids Z-D/L-Trp (Z = benzyloxycarbonyl), Ac-D/L-Trp (Z = acetyl) with β-cyclodextrins (β-CDs) modified with D/L-Trp moiety and D/L-naphtylalaine moiety (D/L-Trp-β-CD and D/L-Naph-β-CDs) were determined by isothermal titration microcalorimetry. Interaction of Z-D/L-Trp with D/L-Trp-β-CD revealed no chiral discrimination. Affinities were smaller than that observed with native β-CD, however enthalpies were more negative in the case of D/L-Trp-β-CD. Affinities of Ac-D/L-Trp toward D/L-Trp-β-CD were higher than that toward native β-CD in 2-5 times. Binding properties of D-Trp-β-CD were quite different from the properties of L-Trp-β-CD, although both hosts exhibited no enantioselective abilities. Similarly to D/L-Trp-β-CD, D/L-Naph-β-CD also exhibited very low ability to discriminate between enantiomers of Ac-Trp. Upon interaction of two opposite enantiomers of Ac-Trp with L-Naph-β-CD quite different reaction enthalpies were observed. Nevertheless, stability of Ac-D-Trp + L-Naph-β-CD and that of Ac-L-Trp + L-Naph-β-CD complexes were practically the same due to common enthalpy-entropy compensation.
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