Polysaccharide derivative and separating agent for optical isomer containing the same
The present invention provides: a polysaccharide derivative containing a structure wherein hydrogen atoms in a hydroxyl group at the 2-position and the 3-position of a structure unit of polysaccharide are substituted with different substituents respectively represented by a specific general formula and a separating agent for optical isomers which contains such a polysaccharide derivative. The present invention can provide a novel polysaccharide derivative which has excellent optical isomer separating ability, making it suitable as a separating agent for optical isomers, and can provide a separating agent for optical isomers which contains the polysaccharide derivative.
1. A method of producing a polysaccharide derivative, comprising the steps of (a) or (b):
(a) modifying a hydroxyl group or amino group at a 2-position of structural units of a polysaccharide with a first substituent represented by a benzoyl group; and
modifying a hydroxyl group or amino group at a 3-position of the structural units with a second substituent represented by the following general formula (II):
—CO—NH—R (II),
or
(b) modifying a hydroxyl group or amino group at a 2-position of structural units of a polysaccharide with a first substituent represented by a 4-chlorophenylcarbamoyl group; and
modifying a hydroxyl group or amino group at a 3-position of the structural units with a second substituent represented by any one of the following general formulae (I) to (III) and different from the first substituent:
—CO—R (I)
—CO—NH—R (II)
—R (III)
wherein R represents an aliphatic or aromatic hydrocarbon group which may contain a heteroatom, and the group may further have a substituent.
2. The method according to claim 1 , wherein:
the structural units each are a hexose further having a hydroxyl group or amino group at its 6-position; and
the method further comprises the step of protecting the hydroxyl group or amino group at the 6-position with a protective group after modifying the hydroxyl group or amino group at the 2-position.
3. The method according to claim 2 , further comprising the steps of:
removing the protective group at the 6-position after modifying the hydroxyl group or amino group at the 3-position; and
modifying the hydroxyl group or amino group at the 6-position from which the protective group has been removed with a third substituent represented by any one of the general formulae (I) to (III) and different from the second substituent.
4. A method of producing a polysaccharide derivative, comprising:
a 2-position protecting step of protecting a hydroxyl group or amino group at a 2-position of structural units of a polysaccharide with a protective group;
a 3-position modifying step of modifying a hydroxyl group or amino group at a 3-position of the structural units, the 2-position of which has been protected, with a second substituent represented by the following general formula (II) different from the first substituent;
a 2-position deprotecting step of removing the protective group at the 2-position in the structural units, the 3-position of which has been modified; and
a 2-position modifying step of modifying the hydroxyl group or amino group at the 2-position from which the protective group has been removed with a first substituent represented by 4-chlorophenylcarbamoyl group:
—CO—NH—R (II)
wherein R represents an aliphatic or aromatic hydrocarbon group which may contain a heteroatom, and the group may further have a substituent.
5. The method according to claim 4 , wherein:
the structural units each are a hexose further having a hydroxyl group or amino group at its 6-position; and
the 3-position modifying step is a step of modifying each of the hydroxyl groups or amino groups at both the 3- and 6-positions of the structural units with the second substituent.
6. The method according to claim 5 , wherein:
the 2-position deprotecting step is a step of removing both the protective group at the 2-position and the second substituent at the 6-position; and
the 2-position modifying step is a step of modifying each of the hydroxyl groups or amino groups at both the 2- and 6-positions of the structural units with the first substituent.
7. The method according to claim 4 , wherein:
the structural units each are a hexose further having a hydroxyl group or amino group at its 6-position;
the method further comprises
a 6-position protecting step of protecting the hydroxyl group or amino group at the 6-position of the structural unit, the 2-position of which has been protected, with a protective group before the 3-position modifying step,
a 6-position deprotecting step of deprotecting the protective group at the 6-position in the structural unit the 3-position of which has been modified in the 3-position modifying step before the 2-position deprotecting step, and
a 6-position modifying step of modifying the hydroxyl group or amino group at the 6-position from which the protective group has been removed with a third substituent represented by the same general formula as the general formula of each of the first and second substituents but different from the first and second substituents; and
the 2-position deprotecting step is a step of removing the protective group at the 2-position in the structural unit, the 6-position of which has been modified.