142187-75-5Relevant articles and documents
Synthesis of branched cyclodextrins using activated carbon as a catalyst
Ishikura, Kandai,Yanagihara, Kazunori,Takagi, Hiroki
, p. 91 - 99 (2021)
Activated carbon has been reported to act as a catalyst for condensation reactions between glucose molecules. The present study describes the use of activated carbon as a new catalyst for the synthesis of branched cyclodextrins (CDs). Two main methods have been used to synthesize branched CDs: a method using an enzymatic condensation or transfer reaction, and a method using a chemical reaction. However, these methods have problems such as a limited number of the types of branched CDs that can be synthesized that depend on the characteristics of the enzyme, the long reaction time required (several days or more), difficulty in synthesizing branched CD with a high degree of substitution (DS), the need for large quantities of environmentally harmful solvents, and a complicated and costly reaction. Using activated carbon as a catalyst, branched CDs with a high DS could be synthesized within a relatively short time (a few hours), regardless of the type of saccharide in the branched portion. Furthermore, since the reaction was conducted under solvent-free conditions using activated carbon, the amount of solvent used in the production of branched CD could be reduced. The branched β-CDs prepared using the activated carbon catalyst showed high solubility, high solubilization capacity, and low hemolytic activity, similar to the 2-hydroxypropyl-β-CD used for pharmaceuticals. These results indicate that activated carbon is an industrially and environmentally useful catalyst for branched CD syntheses.
ENZYMIC SYNTHESES OF DOUBLY BRANCHED CYCLOMALTOHEPTAOSES THROUGH THE REVERSE ACTION OF Pseudomonas ISOAMYLASE
Abe, Jun-ichi,Hizukuri, Susumu,Koizumi, Kyoko,Kubota, Yoko,Utamura, Toshiko
, p. 87 - 96 (2007/10/02)
Two and three new cyclomaltoheptaose (β-cyclodextrin, cG7) derivatives, respectively, were identified among the products obtained by the action of Pseudomonas isoamylase on maltose and maltotriose, and cG7.They were 6A,6D-di-O-α-maltosyl-cG7 and 6-O-α-(62-O-α-maltosyl)maltosyl-cG7, and 6A,6D-di-O-α-maltotriosyl-cG7, 6-O-α-(63-O-α-maltotriosyl)maltotriosyl-cG7, and 6-O-α-(62-O-α-maltotriosyl)maltotriosyl-cG7.In addition, 61- and 62-O-α-maltosylmaltose were identified as mutual condensation products of maltose.Maltose was the smallest substrate to act as both an acceptor and a donor for the action of Pseudomonas isoamylase.
ISOLATION AND CHARACTERIZATION OF BRANCHED CYCLODEXTRINS
Koizumi, Kyoko,Utamura, Toshiko,Sato, Michikatsu,Yagi, Yoshiaki
, p. 55 - 68 (2007/10/02)
Three branched cyclodextrins (CDs) were isolated by high-performance liquid chromatography (l.c.) from the mother liquors of a large-scale preparation of the unbranched CDs with Bacillus ohbensis cyclomaltodextrin glucanotransferase.Evidence from chromatographic behavior on three l.c. coloumns of different separation modes, fragmentation analysis, 13C-n.m.r. spectroscopy, methylation analysis, and fast-atom bombardment-mass spectroscopy (f.a.b.-m.s.) indicated that these compounds were 6-O-α-D-glucopyranosylcyclomaltohexaose (1), 6-O-α-D-glucopyranosylcyclomaltoheptaose (2), and 6,6'''-di-O-α-D-glucopyranosylcyclomaltoheptaose (3).
