TY - JOUR
T1 - Multifunctional hydrolytic catalysis. II. Hydrolysis of p-nitrophenyl acetate by a polymer catalyst which contains hydroxamate and imidazole functions
AU - Kunitake, Toyoki
AU - Okahata, Yoshio
PY - 1975/6
Y1 - 1975/6
N2 - A water-soluble polymer catalyst was prepared by radical polymerization of a protected hydroxamate monomer, 1-methyl-2-vinylimidazole and acrylamide, and by the subsequent NH2NH2 treatment of the polymer. The hydrolysis of p-nitrophenyl acetate by the bifunctional copolymer obeyed typical burst kinetics: rapid accumulation of acetyl hydroxamate group and its slow decomposition. The acetylation rate of the hydroxamate group was rather close to that of a polymer which does not contain the imidazole unit. However, the deacylation was markedly accelerated by the presence of the imidazole unit, and the difference in rate constants amounted to 60- to 80-fold at pH 8-9. These results indicate that the overall catalytic efficiency of the bifunctional polymer is enhanced due to the complementary action of the imidazole and hydroxamate functions.
AB - A water-soluble polymer catalyst was prepared by radical polymerization of a protected hydroxamate monomer, 1-methyl-2-vinylimidazole and acrylamide, and by the subsequent NH2NH2 treatment of the polymer. The hydrolysis of p-nitrophenyl acetate by the bifunctional copolymer obeyed typical burst kinetics: rapid accumulation of acetyl hydroxamate group and its slow decomposition. The acetylation rate of the hydroxamate group was rather close to that of a polymer which does not contain the imidazole unit. However, the deacylation was markedly accelerated by the presence of the imidazole unit, and the difference in rate constants amounted to 60- to 80-fold at pH 8-9. These results indicate that the overall catalytic efficiency of the bifunctional polymer is enhanced due to the complementary action of the imidazole and hydroxamate functions.
UR - http://www.scopus.com/inward/record.url?scp=0016703962&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0016703962&partnerID=8YFLogxK
U2 - 10.1016/0045-2068(75)90003-6
DO - 10.1016/0045-2068(75)90003-6
M3 - Article
AN - SCOPUS:0016703962
VL - 4
SP - 136
EP - 148
JO - Bioorganic Chemistry
JF - Bioorganic Chemistry
SN - 0045-2068
IS - 2
ER -