TY - JOUR
T1 - Electronic substituent effects in the nitrilase-catalyzed hydrolysis of para-substituted benzyl cyanides
AU - Geresh, Shimona
AU - Giron, Yakir
AU - Gilboa, Ygal
AU - Glaser, Robert
PY - 1993/1/1
Y1 - 1993/1/1
N2 - The initial rates of the nitrilase (Novo)-catalyzed hydrolysis of a series of para-substituted benzyl cyanides (R = NO2, Cl, OCH3, OH, NH2) were found to be susceptible to the nature of the para-substituent of the substrate and a Hammett-type linear free energy correlation was observed with ρ{variant} = 0.96. In a separate study, effective solubilization of substituted benzyl cyanide substrates having electron-donating groups (OH, NH2, OCH3) was achieved upon mixing with β-cyclodextrin to form 1:1 mol ratio inclusion complexes, but para-substituted benzyl cyanides with electron-withdrawing groups (Cl, NO2) were not fully solubilized under the same conditions. In addition, it was shown that the presence of β-cyclodextrin not only had no inhibitory effect on the enzyme activity, but it actually increased the initial rate of hydrolysis of the unsubstituted benzyl cyanide:β-cyclodextrin inclusion complex. However, the initial rates of hydrolysis were observed to be smaller when β-cyclodextrin was added to the para-substituted benzyl cyanides.
AB - The initial rates of the nitrilase (Novo)-catalyzed hydrolysis of a series of para-substituted benzyl cyanides (R = NO2, Cl, OCH3, OH, NH2) were found to be susceptible to the nature of the para-substituent of the substrate and a Hammett-type linear free energy correlation was observed with ρ{variant} = 0.96. In a separate study, effective solubilization of substituted benzyl cyanide substrates having electron-donating groups (OH, NH2, OCH3) was achieved upon mixing with β-cyclodextrin to form 1:1 mol ratio inclusion complexes, but para-substituted benzyl cyanides with electron-withdrawing groups (Cl, NO2) were not fully solubilized under the same conditions. In addition, it was shown that the presence of β-cyclodextrin not only had no inhibitory effect on the enzyme activity, but it actually increased the initial rate of hydrolysis of the unsubstituted benzyl cyanide:β-cyclodextrin inclusion complex. However, the initial rates of hydrolysis were observed to be smaller when β-cyclodextrin was added to the para-substituted benzyl cyanides.
UR - http://www.scopus.com/inward/record.url?scp=0027487835&partnerID=8YFLogxK
U2 - 10.1016/S0040-4020(01)80205-2
DO - 10.1016/S0040-4020(01)80205-2
M3 - Article
AN - SCOPUS:0027487835
SN - 0040-4020
VL - 49
SP - 10099
EP - 10102
JO - Tetrahedron
JF - Tetrahedron
IS - 44
ER -