Organic compounds -- part of the class 532-570 series – Organic compounds – Carbohydrates or derivatives
Patent
1995-12-29
1998-03-31
Wilson, James O.
Organic compounds -- part of the class 532-570 series
Organic compounds
Carbohydrates or derivatives
536 41, 536 185, 536 45, 536 551, 536 56, 536 58, 536102, 5361231, 523218, 523219, 521 54, 521 55, 521 57, 521 841, 5211091, C08B 300, C08B 3000
Patent
active
057340439
DESCRIPTION:
BRIEF SUMMARY
FIELD OF INDUSTRIAL APPLICATION
The present invention relates to a separating agent for optical isomers, particularly to a separating agent useful for the optical resolution of racemic compounds, which comprises a polysaccharide derivative supported on a silica gel having its surface silanol treated with a silylating agent having an aralkyl group.
PRIOR ART
It is known that a packing material comprising a polysaccharide derivative supported on a silica gel is useful as a separating agent for optical isomers from racemic compounds (Y. OKAMOTO, M. KAWASHIMA and K. HATADA, J. Am. Chem. Soc., 106, 5357, 1984). Such a separating agent is supported on a carrier, such as a silica gel, wherein the surface silanols causative of specific adsorption or other troubles have been suitably treated, e.g., an aminopropylated silica gel or a carbamoylated silica gel obtained by further reacting the aminopropyl groups with 3,5-dimethylphenyl isocyanate. However, when such a separating agent is used as a packing material for reversed-phase liquid chromatography, it has defects such as the instability of the base line in a liquid chromatograph, a reduced number of theoretical plates for a detected peak in the measurement, and the elution of a low-molecular portion of the polysaccharide derivative depending on the composition of the mobile phase. One of the reasons for such defects is supposedly a poor affinity of the silylating agent on the silica gel surface for the polysaccharide derivative, in other words, the instability of the polysaccharide derivative on the carrier.
Under these circumstances, there has been demanded a separating agent which, when used as a packing material for reversed-phase liquid chromatography, has excellent baseline stability of the and number of theoretical plates in the column, in other words, there is an excellent affinity of the polysaccharide derivative for the silylating agent and, also stability of the polysaccharide on the carrier.
DISCLOSURE OF THE INVENTION
After intensive investigations made for the purpose of developing a separating agent free from the above-described defects and capable of exhibiting the advantageous properties of the polysaccharide derivative to the full, the inventors have attained the present invention.
Namely, the present invention provides a separating agent for optical isomers, which comprises a polysaccharide derivative supported on a silica gel having surface silanol groups treated with a silylating agent having an aralkyl group.
Preferably, the surface silanol groups of the silica gel are treated by reacting the silica gel with a silylating agent in the present invention.
The present invention further provides a process for separating optical isomers from racemic compounds with the above-described separating agent for optical isomers, preferably by reversed-phase liquid chromatography, wherein an aqueous liquid such as water or an alcohol is used.
The polysaccharide used in the present invention may be any of synthetic, natural and modified natural polysaccharides as long as it is optically active. The polysaccharide is preferably one having a high regularity in its bonding manner. Examples of the polysaccharides include .beta.-1,4-glucan (cellulose), .alpha.-1,4-glucan (amylose or amylopectin), .alpha.-1,6-glucan (dextran), .beta.-1,6-glucan (pustulan), .beta.,1,3-glucan (such as curdlan or shizophyllan), .alpha.-1,3-glucan, .beta.-1,2-glucan (Crown Gall polysaccharide), .beta.-1,4-galactan, .beta.-1,4-mannan, .alpha.-1,6-mannan, .beta.-1,2-fructan(inulin), .beta.-2,6-fructan (levan), .beta.-1,4-xylan, .beta.-1,3-xylan, .beta.-1,4-chitosan, .beta.-1,4-N-acetylchitosan (chitin), pullulan, agarose and alginic acid. They also include amylose-containing starches. Among them, preferred are polysaccharides which can be easily obtained in a highly pure state, such as cellulose, amylose, .beta.-1,4-chitosan, chitin, .beta.-1,4-mannan, .beta.-1,4-xylan, inulin and curdlan, and particularly preferred are cellulose and amylose.
The number-average degree of polymer
REFERENCES:
patent: 4683341 (1987-07-01), Ishii et al.
patent: 5302633 (1994-04-01), Kimata et al.
patent: 5587467 (1996-12-01), Morakami et al.
J. Am. Chem. Soc., 1984, vol. 106, No. 18, pp. 5357-5359.
Murakami Tatsushi
Nishida Nanami
Daicel Chemical Industries Ltd.
Wilson James O.
LandOfFree
Separating agent for optical isomers does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Separating agent for optical isomers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Separating agent for optical isomers will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-53401