Retarding Effects of Cyclodextrins on the Decomposition of Organic Isothiocyanates in an Aqueous Solution
| Autor: | Yoshihisa Matsui, Toshihiko Osawa, Shunro Kawakishi, Yoshio Ohta |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Magnetic Resonance Spectroscopy
Analytical chemistry Linear molecular geometry Applied Microbiology and Biotechnology Biochemistry Analytical Chemistry chemistry.chemical_compound Isothiocyanates Spectroscopy Molecular Biology chemistry.chemical_classification Cyclodextrins Aqueous solution Cyclodextrin Organic Chemistry Water General Medicine Hydrogen-Ion Concentration Solutions Dissociation constant Molecular geometry chemistry Isothiocyanate Proton NMR Physical chemistry Biotechnology |
| Zdroj: | Bioscience, Biotechnology, and Biochemistry. 68:671-675 |
| ISSN: | 1347-6947 0916-8451 |
| DOI: | 10.1271/bbb.68.671 |
| Popis: | One- and two-dimensional (1)H nuclear magnetic resonance ((1)H NMR) spectra were measured in order to estimate the dissociation constants (K(diss)) and molecular geometries of cyclodextrin (CD) with three organic isothiocyanates (ITC), allyl-ITC, 3-butenyl-ITC, and 4-pentenyl-ITC, in an aqueous solution (pH 5.0, I(c)=0.75 M). In every ITC, the K(diss) values decreased in the order of alpha-CDbeta-CDgamma-CD, and the three rod-like linear molecules of ITCs were accommodated with the best fit into the smallest cavity of alpha-CD. By rotating-frame nuclear Overhauser enhancement spectroscopy, cross peaks were found between the H-3 of alpha-CD and the H-1 of AITC. From the result, the molecular geometry of alpha-CD-AITC complex presume that the isothiocyanate group of AITC is located some where around the widening rim and a hydrophobic allyl group is included within the hydrophobic cavity of alpha-CD. |
| Databáze: | OpenAIRE |
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