JPS6238238A - Adsorbent - Google Patents

Abstract

PURPOSE:To obtain an adsorbent having high optical splitting function, by grafting specific polyamino acid to a crosslinked polymer carrier and respectively specifying the upper limit of the crosslinking degree of the carrier and the upper limit of the supporting amount of polyamino acid. CONSTITUTION:Optically active synthetic polyamino acid represented by formula (wherein n is 5 or more, R is an org. group, R' is H or alkyl and R'' is an org. group) is grafted to a crosslinked polymer carrier (e.g., a chloromethylstyrene/styrene/divinylbenzene copolymer) to obtain an adsorbent. The upper limit of the supporting amount of synthetic polyamino acid in this adsorbent is 30% and the upper limit of the crosslinking degree of the carrier is 40%. Further, the crosslinked polymer must have the compatibility with the solvent used in adsorbing operation. That is, when water is used as a solvent, a hydrophilic crosslinked polymer is used and, when an org. solvent is used, an oleophilic crosslinked polymer is used.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a novel adsorbent, particularly a polymer adsorbent having advanced optical resolution capabilities.

BACKGROUND OF THE INVENTION Optical resolution, that is, the separation of racemic mixtures into their optical antipodes, is a very important technique in the pharmaceutical, agricultural, food, and other industries. The usual method is to convert a racemic mixture into a mixture of diastereomers, and then separate the diastereomer mixtures based on the differences in their physical properties, but the types of racemic mixtures that can be separated by this method are limited. It is being

In addition to these conventional methods, techniques for separating racemic mixtures by chromatography have been actively researched and studied in recent years. In this case, an optically active adsorbent 1, for example, a styrene resin carrying optically active L-hydroxyproline, is used as a filler, and the mixture is brought into contact with a divalent copper ion solution to form a complex. There are examples of optical resolution of amino acids by ligand exchange. In this case, the degree of resolution is very low, and copper ions are eluted at the same time as the resolved amino acids, making it difficult to put it to practical use. Other analytical uses include porous silica gel coated with optically active poly(triphenylmethyl methacrylate); It's not durable, so for now,
No method has been found that is satisfactory in terms of durability, cost, ease of manufacture, etc., and it is therefore industrially and technically difficult to apply such a method to the separation of racemates.

Also, known graft polymers (Japanese Patent Publication No. 52-9478)
By grafting a large amount (carrying amount of 60% or more) of a hydrophilic polyamino acid onto a hydrophobic backbone polymer, hydrophilicity is imparted to the backbone polymer, and the resulting polymer is used as a solvent with water. The resin used for racemic resolution of amino acids has problems in the amount of polyamino acid supported and the selection of carrier, and is completely unsuitable as an adsorbent for optical resolution.

The purpose of the present invention is to provide a novel adsorbent that can solve the above-mentioned problems.

The present inventor has conducted intensive research on polymeric adsorbents that have a high degree of substrate selectivity similar to that of enzymes, and has already discovered that crosslinked polymers containing optically active synthetic polyamino acids as constituents have been successfully used for adsorption such as optical resolution. It was discovered that it has excellent performance as an agent that has never been seen before, and it was proposed previously (Japanese Patent Application No. 59-44065). Due to the unique steric structure of the polyamino acid component and the asymmetric environment based thereon, this adsorbent can preferentially adsorb one side of the racemic mixture and perform optical resolution with high efficiency.

Based on this knowledge, the present inventor conducted further intensive studies and found that in an adsorbent in which an optically active synthetic polyamino acid is grafted onto a crosslinked polymer carrier, the degree of crosslinking of the carrier is
The present invention was achieved based on the discovery that an adsorbent having a suitable range for each of the supported amounts of polyamino acid and polyamino acid is an even more excellent adsorbent.

That is, the present invention is based on the general formula % formula % (where n is an integer of 5 or more, R is an organic group, and R' is H
or an alkyl group, R' is H or an organic group) In an adsorbent in which an optically active synthetic polyamino acid represented by the following formula is grafted onto a crosslinked polymer carrier, the upper limit of the degree of crosslinking of the carrier is 40%. The present invention relates to an adsorbent characterized in that the upper limit of the amount of polyamino acid supported is 30%.

Examples of the crosslinked polymer carrier include chloromethylstyrene-styrene-divinylbenzene copolymer, acrylamide-methylenebisacrylamide copolymer, glycidyl methacrylate-ethylene glycol dimethacrylate copolymer, and the like.

The degree of crosslinking of the carrier of the adsorbent of the present invention varies slightly depending on whether or not it is made porous, as described later, but the degree of crosslinking when it is not made porous is 1 to 10%, preferably 2 to 8%. The degree of crosslinking is 1 to 40%, preferably 2 to 16%.
%. When the degree of crosslinking is low, such as less than 1%, mechanical strength is poor and compaction tends to occur when packed into a column.

However, on the other hand, if the degree of crosslinking is too high, exceeding 40%, it is often difficult to introduce the polyamino acid into the carrier, and even if it is possible to introduce the polyamino acid, the polyamino acid is (If the carrier is porous, it also includes the surface of the pores)
Because polyamino acids are supported in association with polyamino acids, their ability to discriminate between optical isomers is not fully demonstrated, and as a result, they do not exhibit excellent resolution.

Synthetic polyamino acid which is a graft component of the adsorbent of the present invention ○ The organic group of R in RR' may be any organic group, but it may be an aromatic group such as an alkyl group or a phenyl group, an aralkyl group, or a complex compound containing nitrogen as an imaginary member. Examples include ring-containing groups, and R and N may be combined to form a ring.

These may be substituted with various groups, examples of substituents include -011, -C0011, -5l+, -Ni+
, , -5C)I, and the like. When having the above substituent, the substituent can also be in the following form.

That is, -〇11, -SH is in the form of ether (e.g. methyl ether, benzyl ether), in the form with an acyl group attached, -
COOH is in the form of an ester or amide, and -NH is in the form with a carbobenzoxy group attached. R' is hydrogen or an alkyl group, and examples of the alkyl group include a methyl group and an ethyl group. R# is hydrogen or an organic group,
Examples of organic groups include carbobenzoxy groups known as amino protecting groups in the field of peptide synthesis, urethane-type protecting groups such as tert-butoxycarbonyl groups, formyl groups, acetyl groups, benzoyl groups, phthalyl groups, and tosyl groups. Examples include acyl-type protecting groups such as , alkyl-type protecting groups such as trityl group, and the like. In this case, a protecting group that is chemically stable and difficult to remove is preferable; for example, even with the same acyl type protecting group, an acetyl group (CH, Go-) is preferable to a formyl group (HCO-).
Alternatively, a benzoyl group (C, H, Co-) or the like is more preferable.

Specific examples of the synthetic polyamino acids (-C-CH-N-+Ir-R' ○ RR') include optically active amino acids constituting proteins, such as alanine, valine, leucine, phenylalanine, proline, etc. and D or derivatives of proteinogenic amino acids such as β-benzylaspartate, γ-methylglutamate, γ-benzylglutamate, ε-carbobenzoxylysine, δ-carbobenzoxyornithine, O-acetyltyrosine, and O-benzylserine. L
Optical activity α other than amino acids constituting proteins
-Aminocarboxylic acids (eg sarcosine) and their derivatives are used.

In the above general formula, n (degree of polymerization of supported polyamino acid)
is generally 5 or more and 100 or less, but especially 1
0-40 is preferred. Generally, it is preferable that the degree of polymerization n decreases as the amount of supported polyamino acids increases, in the sense of suppressing association between supported polyamino acids.

The adsorbent of the present invention is a crosslinked polymer containing the above-mentioned optically active synthetic polyamino acid and/or its derivative as a graft component. Because it is derived from active synthetic polyamino acids and/or derivatives thereof,
Any crosslinked polymer other than the graft component may be used.

However, it is necessary that there be an affinity for the solvent used in the adsorption operation.

That is, when using water as a solvent, a hydrophilic crosslinked polymer,
Furthermore, when using an organic solvent such as toluene or dioxane, it is necessary to use a lipophilic crosslinked polymer as a carrier.

As described above, by appropriately selecting the type of carrier depending on the solvent system used, the interaction between the separation target and the carrier can be suppressed, and the separation target can be effectively separated only with the supported polyamino acid. As a result, excellent separation performance is achieved.

The upper limit of the amount of synthetic polyamino acids supported on the adsorbent is 30
%, and can be appropriately selected within that range, but is preferably 20% or less. If the upper limit of the supported amount exceeds 30%, the supported polyamino acids will associate with each other, resulting in a decrease in separation performance. In addition, the adsorption effect of the adsorbent of the present invention varies depending on the solvent system used as described above, but it also depends on the functional groups, stericity, etc. of the substance to be adsorbed. The type of amino acid, etc. can be changed as appropriate.

For example, the amino acid constituent units R, R', and R' may be varied in one molecule.

The adsorbent of the present invention can be manufactured by the following method. First, the N-carboxy anhydride (hereinafter referred to as
(referred to as NCA) is synthesized from the corresponding optically active amino acid or its side chain derivative by a known method such as reaction with phosgene.

Details of this method can be found, for example, in Murray Gutsman (M.
Goodman), Biopolymer
Mars), Volume 15, Page 1869 (1976).

Next, a crosslinked polymer carrier having a functional group convertible into an amino group or into which an amino group can be introduced is produced by a known method, and the functional group is converted into an amino group or an amino group is introduced.

The NCA is polymerized using the carrier having an amino group as an initiator to obtain a crosslinked polymer in which an optically active synthetic polyamino acid is supported on the carrier. At this time, the upper limit of the degree of crosslinking of the carrier polymer is set to 40%. The upper limit of the degree of crosslinking is set to 40
% can be achieved by setting the upper limit of the proportion of the crosslinking agent in all monomers to 40% when synthesizing the carrier polymer.

Further, the upper limit of the amount of polyamino acid supported can be set to 30% by appropriately adjusting the amount of NCA used when supporting the polyamino acid depending on the amount supported.

Then, if necessary, the terminal amino group of the supported polyamino acid is protected with a suitable protecting group among the above-mentioned protecting groups, thereby containing as a constituent an optically active synthetic polyamino acid with the desired amino terminal protected. A crosslinked polymer is obtained.

If the supported optically active synthetic polyamino acid has a convertible side chain, it can be converted into an optically active polyamino acid with a different chemical structure by chemically converting it, for example, by converting an ester group into an amide group. can be converted into active synthetic polyamino acids. When converting an ester group to an amide group, in addition to the usual ammonolysis, the ester can be converted to cyanoethyl ester, chloroethyl ester, or trichloroethyl ester.

After converting an electron-withdrawing substituent such as a trifluoroester into a functional ester, it is reacted with an amine such as benzylamine, cyclohexylamine, L-α-phenylethylamine, or L-α-amino-ε-caprolactam. You can also do it. This chemical conversion is one of the very important manufacturing steps in obtaining an adsorbent suitable for the separation target because it allows the introduction of functional groups that perform interactions such as hydrogen bonding. The terminal amino group of the polyamino acid is protected as necessary before or after the reaction. Examples of the crosslinked polymer carrier having a functional group convertible into an amino group or into which an amino group can be introduced include the above-mentioned chloromethylstyrene-styrene-divinylbenzene copolymer and acrylamide-methylenebisacrylamide copolymer. .

Examples include glycidyl methacrylate-ethylene glycol dimethacrylate copolymers, but in short, monomers that have a functional group that can be converted into an amino group such as chloromethylstyrene, or a functional group that can introduce an amino group such as glycidyl methacrylate. Any crosslinked polymer polymerized using monomers as monomer components may be used.

Suspension polymerization of these copolymers is carried out, for example, by the following method. First, the reaction raw material is an inert organic solvent, preferably an aromatic hydrocarbon such as benzene or toluene, or n-
It is dissolved in aliphatic hydrocarbons such as octane or alcohols such as cyclohexanol and lauryl alcohol. As for the amount of organic solvent, it is particularly advantageous to use 1 part by weight of the solvent per 1 part by weight of the reaction raw material, provided that the monomer can be completely dissolved, but in general, 0 to 3 parts by weight of the solvent is used. It will be done. This reaction solution is well mixed with an aqueous protective colloid solution, especially an aqueous polyvinyl alcohol solution, using an efficient stirrer, for example, using 2 to 25 parts by weight of the aqueous solution per 1 part by weight of this reaction solution. The stirred mixture is heated to about 40°C to 100°C, preferably about 70°C, under an atmosphere of non-reactive gas, particularly nitrogen. Polymerization time is about 4 hours to 72 hours, preferably about 10 hours.

In this case, a porous spherical gel can be obtained by adding a suitable diluent to the seven-mer phase.

As for the type of diluent, organic solvents that have low swelling properties for the resulting gel are suitable. For example, chloromethylstyrene
In the case of a styrene-divinylbenzene copolymer, octane, decane, dodecane, etc. are preferred. Alternatively, instead of a diluent, a linear polymer such as polystyrene, polymethylstyrene, polymethyl acrylate, etc. may be present in the coexistence for polymerization, and then the linear polymer may be extracted and removed from the resulting spherical gel to form a porous spherical gel. can. Porous formation is applied to low and high degree of crosslinking, but is generally applied to high degree of crosslinking, and the resulting porous spherical gel can absorb the target substance is preferable because it can easily penetrate into the gel and come into contact with functional groups.

Details of the conversion reaction of a functional group in a copolymer into an amino group and the reaction of introducing an amino group can be found, for example, in Merryfield (R
, B, Merriefield) Journal of the American Chemical Society (
J, A, C, S,) Volume 98, Page 7357 (19
76) or Inman (J, K, Inman) Biochemistry, No. 8
Vol., p. 4074 (1969) or Carrar (J.
Die Angew.

Maklomol, Chem, Volume 63, Page 23 (], 977). In addition to the method described in the above literature, for example, in the case of a copolymer having chloromethylstyrene units, amino groups can be introduced by direct reaction with an alkylene diamine such as ethylenediamine or hexamethylene diamine.

After washing the obtained crosslinked polymer carrier having amino groups,
Completely dehydrate by Soxhlet extraction, etc., and thoroughly dry under reduced pressure and heat.

The types of amino groups that initiate polymerization of NCA are usually -
Although primary or secondary amino groups are used.

It is particularly preferable to use a -grade amino group as the initiator because it can support the polyamino acid quantitatively.

The reaction conditions for the terminal amino group protection reaction are appropriately determined depending on the type of reaction reagent. As a typical example, when protecting with an acetyl group, the crosslinked polymer supporting the polyamino acid is swollen with an appropriate solvent such as dioxane, and acetic anhydride is added in an amount of 1 to 1000 times the terminal amino group. It can be obtained by stirring at a temperature of 70°C to 70°C.

Separation methods using the adsorbent of the present invention generally include batch methods and column chromatography methods. When performing highly difficult separations such as separation of optically active substances, it is preferable to obtain a crosslinked polymer by S turbidity polymerization, size the particles, and perform separation by column chromatography using the resulting particles as an adsorbent.

Column chromatography is usually carried out using the following procedure. First, the adsorbent is suspended in the solvent used for elution, and the suspension is transferred to the column. The object to be separated is dissolved in a small amount of solvent, this solution is transferred to the top of a column, and this column is treated with an eluent.

The eluate is collected into individual fractions in a conventional manner.

The degree of racemic resolution can be determined by measuring the optical rotation of each fraction.

Using the crosslinked polymer adsorbent according to the invention, it is possible to resolve a large variety of racemic mixtures. For example, hydroxycarboxylic acids, amino acids, and derivatives of these compounds, such as N-carbobenzoxy and N-benzoyl derivatives of amino acids such as phenylalanine, valine, leucine, tryptophan, serine, and methionine, as well as hydantoin derivatives, chlorthalidone, and pantoyl lactone. It is very useful as an adsorbent for optical resolution.

In an adsorbent in which an optically active synthetic polyamino acid is grafted onto a crosslinked polymer carrier, by setting the upper limit of the degree of crosslinking of the crosslinked polymer carrier to 40%, it is possible to introduce the polyamino acid without association. As a result, separation and resolution performance can be improved. Furthermore, by setting the upper limit of the supported amount of polyamino acids to 30%, it is possible to prevent the polyamino acids from associating with each other, thereby increasing their ability to separate and divide.

Although the present invention will be specifically explained in the following production examples and examples, the present invention is not limited to these production examples and examples.

Production Example 1 Chloromethylstyrene 2.379.55% Divinylbenzene (crosslinking agent) 78.06%, Styrene 277.35%
75% dibenzoyl peroxide 4,789, n-
A solution of 304.129 parts of octane (diluent) was added to a solution of 20.01 parts of polyvinyl alcohol and 2000 parts of water.

This mixture was stirred at 1000 rpm for 10 hours at 70° C. under nitrogen to produce a crosslinked polymer of chloromethylstyrene-styrene-divinylbenzene copolymer having a crosslinking degree of 12%. The crosslinked polymer was collected by filtration, washed with hot water, methanol and acetone, and then dried under reduced pressure at about 60°C. The resulting crosslinked polymer was a porous white spherical gel that was insoluble in common organic solvents.

This cross-linked polymer 2509 for carrier was mixed with toluene 2000-
to which ethylenediamine 607 was added and 90
The mixture was stirred at <RTIgt;C</RTI> for 10 hours to convert the chloromethyl groups in the crosslinked polymer to N-(aminoethyl)aminomethyl groups. After the reaction, the crosslinked polymer was collected by filtration, thoroughly washed, and completely dried. The nitrogen content of this product was 0.096%. The obtained aminated crosslinked polymer carrier 220i was
Methyl-1-glutamate NCA37 was dispersed in a solution of 2200 d of 1,2-dichloroethane and heated at 30°C under nitrogen.
The mixture was stirred for 40 hours to polymerize NCA, and the polyamino acid was grafted onto the crosslinked polymer carrier. After the reaction, a part of the amino acid graft crosslinked polymer was isolated, purified and analyzed, and the nitrogen content was found to be 1.12%. The amount of poly(γ-methyl-L-glutamate) supported was calculated from this value to be 10.9%, and the degree of polymerization was 24.9.

After the polymerization reaction, 181.2# of ethylene cyanohydrin and 66 molecules of P-toluenesulfonic acid (monohydrate) as a catalyst were added to the crosslinked polymer dispersion, stirred at 60°C for 3 hours, and then the reaction system was The reaction mixture was further stirred for 6 hours under reduced pressure while methanol produced by the reaction was distilled off together with the solvent to carry out transesterification. After the reaction, the cyanoethyl esterified crosslinked polymer was isolated, thoroughly washed, and then completely dried.

The elemental analysis values of this product were as follows.

C: 86.72 (%) H: 7.58 N: 1.75 Based on the nitrogen content, the reaction rate (conversion rate from methyl ester to cyanoethyl ester) is estimated to be about 70%. In the infrared absorption spectrum of this product, a characteristic absorption of the nitrile group was observed at 2250 (!-1).

The mixture was dispersed in 1800 ntQ of N-dimethylformamide, added with 225 benzylamine molecules, stirred at 55°C for 24 hours, and then isolated and purified. In the infrared absorption spectrum, the absorption of nitrile at 2250 cm disappears, and the absorption at 1740 cm
Ester absorption near a+1-1 decreases, and 1650
It can be seen that the cyanoethyl ester was converted to benzylamide from the increase in amide absorption near C11-'.

The conversion rate estimated from the reduction in ester absorption was about 70%.

Elemental analysis value C: 87.40 (%) H: 7.
58 N: 1.45 200 i of this benzylamidated crosslinked polymer was diluted with 1200 ml of dioxane. It was dispersed in a solution of 40 mQ of acetic anhydride, stirred at 30°C for 24 hours, and then isolated and purified.

When the acid adsorption capacity of the crosslinked polymer after the reaction was measured using N150-1 (Cfi dioxane solution), the adsorption capacity was approximately Omeq/2, indicating that the terminal amino group was completely protected by the acetyl group. Almost no changes were observed in the infrared absorption spectrum and elemental analysis values.

Title 1dL: 5.93 i of chloromethylstyrene, 32.53 g of 55% divinylbenzene, 319.32 g of styrene - 17
A solution of 4.789% dibenzoyl peroxide and 214.79% n-octane was dispersed in a 1% aqueous polyvinyl alcohol solution, and the same method as in Production Example 1 was used to obtain chloromethylstyrene-styrene-divinyl with a degree of crosslinking of 5%. A crosslinked benzene copolymer carrier was produced. The resulting crosslinked polymer was a porous milky white spherical gel that was insoluble in common organic solvents.

This crosslinked polymer was reacted with ethylenediamine in the same manner as in Production Example 1 to obtain an aminated crosslinked polymer carrier having a nitrogen content of 0.24%. 200 of the resulting aminated crosslinked polymer carriers were converted into γ-methyl-L-glutamate NCA3.
The NCA was dispersed in a solution of 2,400 ml of 1,2-dichloroethane and stirred under nitrogen at 30° C. for 40 hours to polymerize the NCA and graft the polyamino acid onto the crosslinked polymer. The nitrogen content in the crosslinked polymer after the supporting reaction was 1.79%. The amount of poly(γ-methyl-L-glutamate) supported was calculated from this value to be 15.8%, and the degree of polymerization was 15.3.

After the polymerization reaction, in the same manner as in Production Example 1, the side chain of the supported polyamino acid was converted from methyl ester to benzylamide.

The conversion rate estimated from the amount of decrease in ester absorption in the infrared absorption spectrum was about 75%.

After the side chain conversion reaction, the terminal amino group of the supported polyamino acid was protected with an acetyl group in the same manner as in Production Example 1.

Various adsorbents were produced by changing the degree of cross-linking of the carrier and the amount of polyamino acid supported, respectively, in exactly the same manner as in Production Examples 1 and 2. The results are shown in Table 1. Shown below.

The adsorbents produced in Production Examples 1 and 2 were classified using metal sieves of 250 mesh and 400 mesh, respectively, and the diameter was 37 mm.
~63 μs were collected. This classified crosslinked polymer was used as a packing material and packed into a stainless steel column under the following conditions. A Shimabara LC-4A type high-performance liquid chromatography device was used as the liquid pump, and a large bunker manufactured by Gascro Industries Co., Ltd. was used as the packer.The filling was carried out by a constant pressure method.

(Left below) Column: Inner diameter 16.7mm, length 500mm Filling liquid: 4
Toluene-dioxane mixed liquid pressure = 80 atmospheres Temperature: Room temperature Both adsorbents could be filled without any problem under the above filling conditions, and no problem of compaction occurred. Next, using this packed column, the retention time of each of D and L-mandelic acid was measured by chromatography to evaluate the separation ability of the adsorbent. A Shimabara LC-4A high performance liquid chromatography device was used for liquid delivery and detection. The chromatography conditions are as follows.

Eluent: 4:1 toluene-dioxane mixture Flow rate: 2
d1 minute temperature: 10°C Detection: Differential refractometer Sample amount: 2% solution 2d Table 2 shows the results of measuring the retention times of each of D-mandelic acid and L-mandelic acid. The separation coefficient α, which represents the optical resolution ability of the adsorbent, was calculated using the following formula.

TD: Retention time of leaf mandelic acid TL: Retention time of L-mandelic acid TO: Retention time of l-luene When α = 1, the separation coefficient indicates that there is no optical resolution at all, and the difference from 1 is large. This indicates that the optical resolution increases as the value increases.

As shown in Table 2, both adsorbents have a separation coefficient of 1.
10, indicating excellent separation characteristics.

(The following is a blank space.) The adsorbent produced in Production Example 2 was classified in the same manner as in Examples 1 and 2, and packed into a column.

When DL-isopropylhydantoin was resolved using this column under the following conditions, it was almost completely separated into D and L optical isomers, with retention times of 65.00 minutes and 70.91 minutes, respectively. , the separation factor was 1.26.

Eluent: 3:1 toluene-dioxane mixture Flow rate: 2
mQ/min Temperature = 10°C Detection: Differential refractometer Sample amount 20.5% solution 2 mQ
, 2 was classified under the same conditions as in 2, and packed into a stainless steel column. Table 3 shows the results of evaluating the packed column using mandelic acid in the same manner as in Example 1.2. It can be seen that all adsorbents have extremely poor optical resolution.

From the above Table 3, it can be seen that when the degree of crosslinking of the crosslinked polymer carrier and the amount of polyamino acid supported are each within the range of the present invention, an adsorbent exhibiting excellent separation properties and having high practicality can be obtained. .

The upper limit of the degree of crosslinking of the crosslinked polymer carrier is 40%, and the upper limit of the amount of polyamino acids supported is 30%. The adsorbent has a three-dimensional structure, exhibits excellent separation characteristics because it interacts effectively with the object to be separated, and provides an adsorbent with excellent performance and high practicality.

Claims (1)

[Claims] (1) General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, n is an integer of 5 or more, R is an organic group, and R' is H
or an alkyl group, R'' is H or an organic group) In an adsorbent in which an optically active synthetic polyamino acid represented by An adsorbent characterized in that the upper limit of the amount of polyamino acid supported is 30%.