KR100520998B1 - Liquid Chromatographic Crown Ether Chiral Statioary Phases with Double Tethering Groups and Chiral Columns Packed with Them - Google Patents

Abstract

The present invention provides a limited lifetime of chiral stationary phases and chiral columns filled with the optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid covalently bonded to silica gel for LC. The present invention relates to a chiral stationary phase and a chiral column filled with the same, which have been improved by improving the lifespan while maintaining optical splitting performance.

That is, the present invention provides optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid [(2R, 3R, 11R, 12R)-or (2S, 3S, 11S, 12S) -1 (4,7,10,13,16-hexaoxacyclooctadecane-2,3,11,12-tetracarboxylic acid) optically active (18-crown-6) -2,3,11,12-tetracarboxylic anhydride And chiral stationary phases (CSP 1 and CSP 2 ) represented by Chemical Formula 1 prepared by reacting with an aminodialkylsilica gel having a double-linked branch, and chiral LCs filled with the chiral stationary phases (CSP 1 and CSP 2 ) The present invention relates to a column or a chiral column for HPLC, which is intended to drastically increase the lifespan of chiral stationary phases prepared using aminoalkylsilica gels having a single linking branch and chiral column filled with them.

Description

Liquid Chromatographic Crown Ether Chiral Statioary Phases with Double Tethering Groups and Chiral Columns Packed with Them}

The present invention relates to chiral crown ether chiral stationary phases for LCs and chiral columns filled with them, which are known to be very useful for separating two optical isomers constituting chiral pharmaceuticals having primary amino groups. Chiral fixed phases synthesized by covalently bonding the registered optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid to a silica gel for LC and a chiral column filled with them It is possible to manufacture chiral stationary phases and chiral columns filled with them, which have been improved by limiting their lifespan, while dramatically improving their lifespan while maintaining optical splitting performance.

Many drugs that exhibit physiological activity are not only optically active, but the racemic drugs are composed of two optical isomers that are mirror images of each other. There is a great need in the development and production of chiral medicines for the separation of two optical isomers and the need for LC chiral stationary phase and chiral column to measure the optical purity of optically active medicines.

Since many chiral drugs have a primary amino group, the necessity of a chiral stationary phase for LC and a chiral column filled with this chiral station which can optically split racemic drugs having a primary amino group is very large. -Crown-6) -2,3,11,12-tetracarboxylic anhydride is covalently bonded to aminopropylsilica gel to synthesize the crown ether chiral stationary phase that can efficiently optically split racemic drugs with primary amino groups The process of preparing a chiral column by filling it has already been developed and patented by the present inventors. (Patent No. 0263872)

However, a chiral stationary phase prepared by covalently binding an anhydride of (18-crown-6) -2,3,11,12-tetracarboxylic acid to an aminopropylsilica gel, which has been previously patented, is a chiral selector (18-crown- 6) Because the 2,3,11,12-tetracarboxylic acid is bound to the surface of the silica gel by a single linking branch, the racemic primary amino compounds can be optically prepared using a reversed-phase mobile phase containing acid under severe conditions of pH 2 In the cleavage process, the chiral selector (18-crown-6) -2,3,11,12-tetracarboxylic acid and the silyl linkage linking the silica gel are damaged so that the chiral selector is liberated from the silica gel, resulting in optical splitting of the chiral column. There is a problem that the performance is degraded and eventually the lifetime as a chiral column is limited.

Accordingly, the present inventors have previously mentioned the aminopropyl silica gel having a single linking anhydride of optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid, which has been previously registered (Patent No. 0263872). A method of preparing a chiral stationary phase by reacting with a bis (trialkoxysilylalkyl) amine was reacted with a silica gel to synthesize an aminodialkylsilica gel having a double-linked branch, which was optically active (18-crown-6). By reacting with anhydrides of) -2,3,11,12-tetracarboxylic acid to prepare a chiral stationary phase having a double-linked branch, and by preparing a chiral column filled with them, a pre-registered chiral stationary phase and chiral filled with them The present invention has been completed for the purpose of providing the chiral stationary phases and chiral columns filled therewith, which have dramatically improved the service life while maintaining the optical splitting performance of the column.

The present invention is a chiral prepared by reacting an anhydride of optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid and aminopropylsilica gel having a single branched branch, developed and pre-registered by the present inventors. To develop a chiral stationary phase represented by the formula (1) which significantly improves the lifespan of the fixed phase and the chiral column filled with them, and significantly improves the life while maintaining the optical splitting performance. To prepare, and to provide an optical separation method of the racemic compounds having a primary amino group using this.

The chiral stationary phase represented by the general formula (1) according to the present invention reacts in the reaction process of the optically active (18-crown-6) -2,3,11,12-tetracarboxylic anhydride and the aminodipropyl silica gel having a double-linked branch. the two types of amino dipropyl chiral stationary phase, which group is present as (CSP 1) and is reacted with the amino groups dipropyl not involved acid chloride to react amino-di-propyl chiral stationary phase (CSP 2) protecting the amino group of not involved It is composed.

CSP 1

         N is an integer of 1-18.

CSP 2

Wherein n is an integer of 1-18 and R is an alkyl or aryl group having 20 carbons or less.

The present invention relates to a chiral stationary phase and a chiral column filled with the above-described optically active (18-crown-6) -2,3,11,12-tetracarboxylic anhydride synthesized by reacting with aminopropylsilica gel for LC. The present invention relates to the development of chiral stationary phases with new double-linked branches and to the development of chiral columns filled with them. Consists of steps.

Reacting bis (trialkoxysilylalkyl) amine with silica gel to synthesize an aminodialkylsilica gel having a double linking branch;

-A chiral stationary phase (CSP 1 ) was synthesized by reacting the synthesized double-linked aminodialkylsilica gel with an anhydride of optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid. Making a step;

Reacting the aminodialkyl group of the silica gel remaining unreacted in the synthesized chiral stationary phase with an acid chloride in the presence of a base to synthesize a chiral stationary phase (CSP 2 ) protecting the amino group of the aminodialkyl group;

Filling the synthesized chiral stationary phase (CSP 1 or CSP 2 ) in a stainless steel blank column to produce a chiral column for LC;

Optically splitting racemic compounds having a primary amino group using a prepared chiral column for LC.

In a specific example of synthesizing a chiral stationary phase (CSP 1 or CSP 2 ) according to the invention, it is possible to prepare bis (trialkoxysilylalkyl) amines and acid chlorides used to remove the amino groups of unreacted aminodialkylsilica gels. There is no limit to the kind.

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments of the present invention, but the scope of protection defined by the appended claims is not limited to the embodiments.

<Example>

1. Preparation of crown ether chiral stationary phases (CSP 1 and CSP 2 )

As an example of a specific method for preparing a crown ether chiral stationary phase according to the present invention, in the formula (1), n = 1 crown ether chiral stationary phase (CSP 1 ) in a specific manufacturing process and the preparation of CSP 1 amino remaining without participating in the reaction specific method of manufacturing the di-protected amino group of the chiral stationary phase silica gel profile (CSP 2, R = t- butyl group) are as follows.

(1) Synthesis of Aminodipropylsilica Gels with Double Linked Branches

To a 500 ml round bottom flask equipped with a Dean-Stark trap, 5.0 g of silica gel and purified 300 ml of toluene are added and refluxed for 2 hours to completely remove moisture adsorbed on the silica gel. .

5.0 ml of bis [3- (trimethoxysilyl) propyl] amine was added to the silica gel from which the water had been removed, and the mixture was refluxed for another 15 hours.

The synthesized aminodipropylsilica gel is filtered using a glass filter, washed with methanol, acetone, ethyl acetate, dichloromethane and hexane in that order and dried.

(2) Preparation of Chiral Fixed Phase (CSP 1 )

2.8 g of aminodipropylsilica gel was added to a 250 ml two-necked round bottom flask equipped with a Dean-Stark trap, and 100 ml of purified toluene was added thereto to reflux for 2 hours. Completely remove the moisture adsorbed on the gel and evaporate the toluene completely using a reduced pressure evaporator.

After toluene is completely removed, 30 ml of dichloromethane and 0.30 ml of 2,6-lutidine are added to the aminodipropyl silica gel and stirred at 0 ° C. for 30 minutes.

To this was slowly added stirring anhydrous (300 mg) of optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid dissolved in 10 ml of purified dichloromethane, and then the whole reaction mixture was added. Stir for 48 hours at room temperature.

After 48 hours, the modified silica gel was filtered using a glass filter, washed with 10 mM sulfuric acid solution containing methanol, 20% methanol, methanol, acetone, ethyl acetate, dichloromethane and hexane, and dried to give a chiral stationary phase (CSP 1). Get)

(3) Protection of amino group of unreacted aminodipropylsilica gel (preparation of CSP 2 )

2.8 g of the chiral stationary phase (CSP 1 ) and 100 ml of purified toluene were added to a 250 ml flask equipped with a Dean-Stark trap and refluxed for 2 hours to completely remove the moisture adsorbed on the CSP 1 . After removal, toluene is completely removed using a vacuum evaporator.

20 ml of dichloromethane and 1.0 ml of 2,6-lutidine are added to the chiral stationary phase (CSP 1 ) from which the moisture is completely removed, and the temperature of the reaction vessel is lowered to 0 ° C.

To this was slowly added 0.5 ml of trimethylacetyl chloride dissolved in 10 ml of purified dichloromethane, followed by stirring for 48 hours.

The modified silica gel was filtered using a glass filter and washed with a sequence of 10 mM sulfuric acid solution containing methanol, 20% methanol, methanol, acetone, ethyl acetate, dichloromethane and hexane followed by drying and not reacting with aminodipropylsilica gel. A chiral stationary phase (CSP 2 ) in which the amino group of is protected is obtained.

2. Preparation of chiral column filled with crown ether chiral stationary phase (CSP 1 or CSP 2 )

The chiral stationary phase (CSP 1 or CSP 2 ) synthesized above is suspended in methanol, and then filled in a column for HPLC or LC using a slurry filler to prepare a chiral column.

3. Example of Optical Splitting

In the present invention, a chiral column filled with a chiral stationary phase (CSP 1 ), which is known in the manufacturing method, is installed in an HPLC apparatus, and a water-methanol (50:50) mixed solvent containing 10 mM sulfuric acid is flowed through the chiral column.

At 20 ^o C, the detector is placed at 210 nm UV and subjected to optical splitting by injecting racemic primary amino compound samples. Examples of the optical splitting are shown in Table 1.

Optical Segmentation of Racemic Primary Amino Compounds Using Chiral Columns Filled with Chiral Stationary Phases (CSP 1 , n = 1) Racemic Sample k ₁ k ₂ α R _S Mobile phase Asphalt Mountain (Asp) 3.70 5.03 1.36 1.92 A Histidine 6.42 9.24 1.44 1.64 A Serin 2.93 7.56 2.58 4.75 A Threonine (Thr) 0.67 1.15 1.72 2.62 A 0 6.38 18.12 2.84 7.73 A 2.28 5.75 2.52 4.90 A 2.48 7.56 3.05 6.20 A 2.30 6.05 2.63 5.20 A 9.35 12.34 1.32 2.38 A 10.39 25.66 2.47 6.13 A

k ₁ and k ₂ are retention facts for the first and second peaks, α is the separation factor, and R _S is the resolution factor. Mobile phase A: 50% aqueous methanol solution + H ₂ SO ₄ (10 mM). Flow rate: 0.5 ml / min. Temperature: 20 ^o C. Detection: 210 nm UV.

The present invention provides a chiral stationary phase by reacting an anhydride of optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid, previously registered, with an aminopropylsilica gel having a single linking branch. The bis (trialkoxysilylalkyl) amine was reacted with silica gel to synthesize an aminodialkylsilica gel having a double-linked branch, which was optically active (18-crown-6) -2,3,11, As shown in the examples of the above optical splitting, the chiral stationary phase having double-linked branches was prepared by reacting with anhydrides of 12-tetracarboxylic acid, and the chiral column filled with them was used. Chiral selection even in harsh mobile phase conditions, such as pH 2, because the connection branches are doubled while maintaining the same or superior optical split performance of chiral columns filled with And silica is dramatically improved as a chiral stationary phase undamaged bond linking the gel life and a process for preparation of a chiral column packed with these.

By using the chiral stationary phase and chiral columns filled with the present invention, optical purity measurement technology necessary in the stage of developing and manufacturing a chiral drug over a long period of time without damaging the chiral column even under severe mobile phase conditions such as pH 2 Has the effect of providing.

Claims (2)

Optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid [(2R, 3R, 11R, 12R)-or (2S, 3S, 11S, 12S) -1,4,7, 10,13,16-hexaoxacyclooctadecane-2,3,11,12-tetracarboxylic acid] and a double linkage represented by the following formula (CSP 1 ) prepared by reacting an aminodialkylsilica gel having a double linkage. Chiral column filled with chiral crown ether chiral stationary phases for LC with branches CSP 1 N is an integer of 1-18 in the above formula. Optically active (18-crown-6) -2,3,11,12-tetracarboxylic acid [(2R, 3R, 11R, 12R)-or (2S, 3S, 11S, 12S) -1,4,7, 10,13,16-hexaoxacyclooctadecane-2,3,11,12-tetracarboxylic acid] participates in the reaction to prepare chiral stationary phase (CSP 1 ) by reacting an aminodialkylsilica gel having a double-linked branch with anhydride The chiral crown ether chiral stationary phases (CSP 2 ) for LCs having a double-linked branch represented by the following formula (CSP 2 ) which are protected by reacting and protecting the amino group of the remaining aminodialkylsilica gel with acid chloride. Filled Chiral Column CSP 2  In the formula, n is an integer of 1-18 and R is an alkyl group having 20 carbons or less and an aryl group.