Abstract
Abstract A series of substituted aryl β -glycosides derived from 3- O - β -cellobiosyl- d -glucopyranose with different phenol-leaving group abilities as measured by the pK a of the free phenol group upon enzymatic hydrolysis has been synthesised. Aryl β -glycosides with a pK a of the free phenol leaving group>5 were prepared by phase-transfer glycosidation of the per- O -acetylated α -glycosyl bromide with the corresponding phenol, whereas the 2,4-dinitrophenyl β -glycoside was obtained by condensation of 1-fluoro-2,4-dinitrobenzene with the partially acetylated trisaccharide followed by acid de- O -acetylation. The aryl β -glycosides have been used for reactivity studies of the wild-type Bacillus licheniformis 1,3-1,4- β - d -glucan 4-glucanohydrolase. The Hammett plot log k cat versus pK a is biphasic with an upward curvature at low pK a values suggesting a change in transition-state structure depending on the aglycon.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
