TY - JOUR
T1 - Synthesis of alternatingly 6-O-methylated cellulose via enzymatic polymerization of a substituted cellobiosyl fluoride monomer catalyzed by cellulase
AU - Okamoto, Etsuya
AU - Kiyosada, Toshitsugu
AU - Shoda, Shin Ichiro
AU - Kobayashi, Shiro
N1 - Copyright:
Copyright 2018 Elsevier B.V., All rights reserved.
PY - 1997
Y1 - 1997
N2 - Novel cellobiose derivatives, 6-O-methyl, 6′-O-methyl, 6,6′-di-O-methyl-β-cellobiosyl fluorides, have been prepared and their hydrolytic behaviour as well as polymerizability by a purified cellulase from Trichoderma viride were investigated. Among these compounds, 6-O-methyl-β-cellobiosyl fluoride was found to polymerize by the cellulase catalysis in a mixed solvent of acetonitrile and acetate buffer (pH 5.0), giving rise to an alternatingly 6-O-methylated cellulose derivative. The stereoselective formation of the β(1 → 4) glycosidic bond is explained by a mechanism involving double inversion at the C1 carbon of the substrate. Another cellobiose derivative, 6′-O-methyl-β-cellobiosyl fluoride, gave a mixture of low molecular weight oligomers. The difference in the observed polymerizability was explained by assuming a difference in steric repulsions between the methyl groups and an amino acid residue at the enzyme catalytic site.
AB - Novel cellobiose derivatives, 6-O-methyl, 6′-O-methyl, 6,6′-di-O-methyl-β-cellobiosyl fluorides, have been prepared and their hydrolytic behaviour as well as polymerizability by a purified cellulase from Trichoderma viride were investigated. Among these compounds, 6-O-methyl-β-cellobiosyl fluoride was found to polymerize by the cellulase catalysis in a mixed solvent of acetonitrile and acetate buffer (pH 5.0), giving rise to an alternatingly 6-O-methylated cellulose derivative. The stereoselective formation of the β(1 → 4) glycosidic bond is explained by a mechanism involving double inversion at the C1 carbon of the substrate. Another cellobiose derivative, 6′-O-methyl-β-cellobiosyl fluoride, gave a mixture of low molecular weight oligomers. The difference in the observed polymerizability was explained by assuming a difference in steric repulsions between the methyl groups and an amino acid residue at the enzyme catalytic site.
KW - 6-O-methyl- -cellobiosyl fluoride
KW - Alternatingly 6-O-methylated cellulose
KW - Cellulase
KW - Enzymatic polymerization
UR - http://www.scopus.com/inward/record.url?scp=0000062598&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0000062598&partnerID=8YFLogxK
U2 - 10.1023/A:1018479621509
DO - 10.1023/A:1018479621509
M3 - Article
AN - SCOPUS:0000062598
VL - 4
SP - 161
EP - 172
JO - Cellulose
JF - Cellulose
SN - 0969-0239
IS - 2
ER -