JP2007332105A - Method for chemical synthesis of pristane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize chemical synthesis of pristane useful for the production of a monoclonal antibody. <P>SOLUTION: The method for the chemical synthesis of pristane contains a step 1 to induce 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol to 3,7,11-trimethyl-dodeca-2,6,10-trienal, a step 2 to induce the 3,7,11-trimethyl-dodeca-2,6,10-trienal obtained by the step 1 to 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol, a step 3 to induce the 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol obtained by the step 2 to 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene, and a step to induce the 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene obtained by the step 3 to pristane. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for producing pristane, and particularly to a method for chemical synthesis of pristane.

  Monoclonal antibody production methods are generally roughly classified into two types: in vitro methods and in vivo methods. The in vitro method is a method in which a monoclonal antibody-producing cell line is cultured in a culture solution, and the monoclonal antibody secreted from the cell line into the culture supernatant is purified and collected. On the other hand, the in vivo method is a method in which a monoclonal antibody-producing cell line is introduced into the abdominal cavity of a laboratory animal such as a mouse and cultured. However, since the in vitro method is difficult to mass-produce monoclonal antibodies and the purification process is complicated and complicated, the in vivo method is recognized as an advantageous production method at least in terms of mass productivity.

  By the way, in the in vivo method, an inducer such as pristane is used in order to promote induction of a cytoma (plasmacytoma) that produces an antibody in the peritoneal cavity of an experimental animal. For example, in Patent Documents 1 and 2, in order to produce a monoclonal antibody that specifically binds to α subunit (hCG-α) or β subunit (hCG-β) of human-derived chorionic gonadotropin, A method is disclosed in which pristane is administered into the abdominal cavity of an experimental animal, a cell line for producing a target monoclonal antibody is transplanted into the abdominal cavity of the experimental animal, and ascites accumulated in the abdominal cavity is collected.

JP 2000-316573 A JP 2000-41672 A

  Pristane is a common name of 2,6,10,14-tetramethylpentadecane (CAS registration number: 1921-70-6) and is sometimes referred to as a common name of Robuoy or Norphytan. It is obtained as a contaminant of natural oil extracted from the liver. However, because the basking shark, which is the source of pristane, has almost no domestic catch, it is only caught several times a year in a stationary net, so its availability has to rely on imports. .

  However, in November 2002, the Washington Convention on the International Trade of Endangered Wild Animals, which currently does not necessarily threaten extinction, but stipulates species that may be extinct unless trade is strictly regulated. In the book II, the shark was published. Under this measure, basking sharks can still be traded for commercial purposes, but imports require a license issued by the authorities of the exporting country based on scientific advice. It is in. For this reason, since 2003, the domestic demand for pristane has been tight and the inventory has already been exhausted, so industrial production by chemical synthesis is desired.

  An object of the present invention is to realize chemical synthesis of pristane.

  The chemical synthesis method of pristane according to the present invention comprises 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol as 3,7,11-trimethyl-dodeca-2,6,10-trienal. Step 1, and 3,7,11-trimethyl-dodeca-2,6,10-trienal obtained in Step 1 is converted to 2,6,10,14-tetramethyl-pentadeca-5,9,13- Step 2 inducing to trien-4-ol, and 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol obtained in Step 2 is converted to 2,6,10,14 -Step 3 leading to tetramethyl-pentadeca-2,6,10,12-tetraene and 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene obtained in step 3 To Pristan And a step 4 of guide.

  In this production method, step 1 is preferably carried out by oxidation of 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol using manganese dioxide. Step 2 is preferably carried out by a reaction between a Grignard reagent having an isobutyl group and 3,7,11-trimethyl-dodeca-2,6,10-trienal.

  Step 3 is preferably carried out by reaction of 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol and paratoluenesulfonic acid monohydrate. At this time, it is preferable to react while 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol and paratoluenesulfonic acid monohydrate are gradually mixed. For example, using one of a micromixer and a microreactor, 2,6,10,14-tetramethyl-pentadec-5,9,13-trien-4-ol and paratoluenesulfonic acid monohydrate It is preferable to react. Furthermore, step 4 is preferably carried out by hydrogenation of 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene in the presence of palladium on carbon.

  Since the chemical synthesis method of pristane according to the present invention includes the steps described above starting from 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol, pristane is chemically treated. Can be synthesized.

  The pristane obtained by the chemical synthesis method of the present invention has an IUPAC name of 2,6,10,14-tetramethylpentadecane and is represented by the following formula (1).

  In the chemical synthesis method of the present invention, 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol is used as a starting material. 3,7,11-Trimethyl-dodeca-2,6,10-trien-1-ol is an alcohol belonging to the acyclic sesquiterpene represented by the following formula (2), which is known by the common name of farnesol. is there.

  Farnesol has E isomer and Z isomer which are geometric isomers, but any geometric isomer can be used in the present invention. A mixture of both isomers can also be used.

  Although farnesol is commercially available, it can be easily obtained, but an unsaturated alcohol such as prenol or geraniol or a carbon chain of a saturated alcohol such as 3-methylbutanol or 3,7-dimethyloctanol is suitable. It can also be produced by extending with a suitable alkylating agent.

  In the present invention, the target pristane is produced mainly by the following four steps starting from the above-mentioned farnesol.

Process 1
The starting material farnesol is derived into 3,7,11-trimethyl-dodeca-2,6,10-trienal represented by the following formula (3).

  In this step, the desired 3,7,11-trimethyl-dodeca-2,6,10-trienal can be obtained by oxidation of farnesol. As the oxidation method of farnesol, a method using manganese dioxide, a method using chromic acid represented by pyridinium dichromate (PDC) and pyridinium chlorochromate (PCC), the Swern method, the Albright-Goldman method, the Pfitzinger-Moffatt method, and A method using dimethyl sulfoxide represented by Parikh-Doering method, a method using organic periodate represented by Dess-Martin reagent and 2-iodoxybenzoic acid (IBX), tetrapropylammonium paltenate (TPAP) ), A method using a ruthenium complex, a method using TEMPO oxidation, a method using quinone, Ishii oxidation, dehydrogenation reaction, oxygen oxidation, and enzymatic oxidation. Can.

  However, in the present invention, it is preferable to employ an oxidation method using manganese dioxide that can be carried out inexpensively and easily. In this method, farnesol is usually dissolved in a solvent, and manganese dioxide is added thereto, followed by stirring at 10 to 50 ° C., preferably 20 to 30 ° C. for about 5 to 20 hours. Examples of the solvent used here include methylene chloride, benzene, toluene, acetone, chloroform, and ethers such as diethyl ether, but methylene chloride is usually preferable.

Process 2
3,7,11-Trimethyl-dodeca-2,6,10-trienal obtained in Step 1 (hereinafter sometimes referred to as “intermediate A”) is represented by 2,6 represented by the following formula (4): , 10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol.

  Here, the target 2,6,10,14-tetramethyl-pentadeca-5 is usually obtained by increasing the carbon atom of the intermediate A with an isobutyl group and converting oxygen of the carbonyl group into a hydroxyl group. 9,13-trien-4-ol can be obtained. At this time, reaction of a typical metal reagent having an isobutyl group or an isobutenyl group (2-methyl-1-propenyl group) with respect to the intermediate A (Method 1), or these typical metal reagent and a transition metal complex were used. A coupling reaction (Method 2) can be employed.

  Typical metal reagents used in Method 1 include isobutylaluminum, isobutenylaluminum, isobutylzinc, isobutenylzinc, isobutyltin, isobutenyltin, isobutylborane, isobutenylborane, isobutyllithium, isobutenyllithium, isobutylzirconium, isobutylzirconium Examples include Grignard reagents having butenylzirconium and isobutyl or isobutenyl groups. Among these, it is preferable to use a Grignard reagent, particularly a Grignard reagent having an isobutyl group. The Grignard reagent having an isobutyl group is obtained by reacting isobutyl chloride, isobutyl bromide or isobutyl iodine with magnesium, and usually isobutyl magnesium chloride is preferred.

  When the method 1 is carried out using a Grignard reagent, the Grignard reagent dissolved in the solvent is added dropwise to the solvent in which the intermediate A is dissolved and stirred. Here, as a solvent for dissolving the intermediate A, for example, anhydrous diethyl ether or tetrahydrofuran can be used. On the other hand, diethyl ether or tetrahydrofuran can be used as the solvent for dissolving the Grignard reagent. Moreover, it is preferable to set normally the temperature at the time of dripping to -20-30 degreeC, and it is more preferable to set to -20-20 degreeC. Furthermore, the temperature during stirring is usually preferably set to -20 to 20 ° C, and more preferably set to 0 to 20 ° C.

  Examples of the transition metal complex used in Method 2 include a palladium complex and a nickel complex. Among these, it is preferable to use a palladium complex.

Process 3
2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol (hereinafter sometimes referred to as “intermediate B”) obtained in step 2 is represented by the following formula (5 To 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene.

  Here, the desired 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene can be obtained by dehydration reaction of the intermediate B. At this time, various known dehydration reactions can be used, but it is preferable to carry out the dehydration reaction while gradually mixing the solvent solution of the intermediate B and the solvent solution of para-toluenesulfonic acid monohydrate. Examples of the solvent used for preparing the solvent solution of the intermediate B include toluene, benzene and xylene. On the other hand, examples of the solvent used for preparing a solvent solution of paratoluenesulfonic acid monohydrate include a 1: 1 mixed solvent of tetrahydrofuran and toluene and a 1: 1 mixed solvent of tetrahydrofuran and benzene. be able to. Moreover, as a reaction apparatus for making it react, mixing both solvent solutions gradually, for example, a micro mixer (for example, Germany, IMM company make) and a microreactor (for example, the trade name "micro flow reactor of Techno Applications Co., Ltd.") are used. ") Can be used. Usually, the temperature during the reaction is preferably set to 60 to 100 ° C, more preferably set to 60 to 80 ° C.

Process 4
Pristane is obtained from 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene (hereinafter sometimes referred to as “intermediate C”) obtained in step 3.

  Here, the target pristane can be obtained by hydrogenation of the intermediate C. Hydrogenation to the intermediate C can be usually performed by adding a catalyst to the solvent solution of the intermediate C and stirring in a hydrogen atmosphere. Examples of the solvent used for preparing the solvent solution of Intermediate C include ethyl acetate, ethanol and methanol. As the catalyst, palladium carbon, a heterogeneous catalyst typified by palladium or platinum, or a homogeneous catalyst typified by Wilkinson reagent can be used, but palladium carbon is preferably used. The temperature during stirring is usually preferably set to 20 to 50 ° C and more preferably set to 20 to 30 ° C.

  In addition, the above-mentioned hydrogenation reaction can also be implemented by the flow system which fixed the catalyst.

  The pristane obtained through the above-described steps can be used as an inducer or the like necessary for the production of a monoclonal antibody by an in vivo method as a substitute for a natural product derived from natural oil extracted from a liver of a shark.

  Pristane was synthesized from farnesol by the reaction route shown in FIG. Details are as follows.

Process 1
Farnesol (mixture of E isomer and Z isomer: Beduquian, USA) 50 g (225 mmol) of methylene chloride solution was added 500 g of manganese dioxide at room temperature (20 ° C.), and the mixture was mixed at room temperature (20 ° C.). Stir vigorously overnight. This reaction solution was filtered through Celite to remove manganese hydroxide produced by the reaction. Then, the solvent was distilled off from the filtrate under reduced pressure to obtain transparent liquid 3,7,11-trimethyl-dodeca-2,6,10-trienal (intermediate A). The resulting intermediate A was used in the next step without purification.

Process 2
Isobutylmagnesium chloride in diethyl ether (2.0 M, 99.8 ml, 200 mmol) was added dropwise at 0 ° C. over 30 minutes to 40 liters (182 mmol) of the intermediate A obtained in step 1 in anhydrous diethyl ether. The reaction solution was further stirred at 0 ° C. for 30 minutes, and then water and a saturated ammonium chloride solution were added to stop the reaction. The reaction solution was washed successively with water, saturated ammonium chloride solution and saturated brine, and the organic matter was extracted with diethyl ether. The organic layer was dried over magnesium sulfate and then filtered, and the solvent was distilled off from the filtrate under reduced pressure to obtain 2,6,10,14-tetramethyl-pentadeca-5,9,13-triene-4 as a transparent liquid. -All (intermediate B) was obtained. The obtained intermediate B was used in the next step without purification.

Process 3
A para-toluenesulfonic acid monohydrate solution (1M, 24.5 g, 129 mmol) was prepared. Here, a mixed solvent of tetrahydrofuran and toluene (mixing ratio = 1: 1) was used as the solvent. Then, this paratoluenesulfonic acid monohydrate solution and the toluene solution of Intermediate B obtained in Step 2 (1M, 35.8 g, 129 mmol) were mixed with a micromixer (manufactured by IMM, Germany). Mix slowly at 0 ° C. At this time, using a syringe pump, the feed rates of the paratoluenesulfonic acid monohydrate solution and the intermediate B toluene solution to the micromixer were each maintained at 0.3 ml / min. In addition, a polytetrafluoroethylene tube having an inner diameter of 1.0 mm and a length of 1 m was connected to the outlet of the reaction apparatus, and the tube was heated to 80 ° C. to keep the residence time of the reaction solution at about 78 seconds. And the reaction solution which flows out from a tube was dripped in the container containing saturated sodium hydrogencarbonate, and reaction was stopped. The reaction solution thus obtained was washed in turn with water and saturated brine, and the organic matter was extracted with diethyl ether. The organic layer was dried over magnesium sulfate and filtered, and the solvent was distilled off from the filtrate under reduced pressure to obtain 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene as a transparent liquid. (Intermediate C) was obtained. The resulting intermediate C was used in the next step without purification.

Process 4
To 10 ml of an ethyl acetate solution of intermediate C (442 mg, 1.70 mmol) obtained in Step 3, 133 mg of 10% palladium carbon was added at room temperature, and the mixture was stirred at room temperature (20 ° C.) for 12 hours in a hydrogen atmosphere. The reaction solution was filtered through Celite, and the solvent was distilled off from the filtrate under reduced pressure. After distillation under reduced pressure at 200 ° C. and 10 mmHg, the purity by gas chromatography analysis (retention time: 10.7 minutes) was 96%. A clear liquid pristane was obtained (yield: 60%). When the obtained pristane was analyzed by ¹ H-NMR and ¹³ C-NMR, the following results were obtained.

¹ H-NMR (CDCl ₃ ): δ = 0.83 to 0.87 (m, CH ₃ , 18H), 0.91 to 0.94 (m, CH ₂ , 2H), 1.08 to 1.28 _{(m, CH 2, 16H)} , 1.36 (m, CH, 2H), 1.50~1.55 (m, CH, 2H)

¹³ C-NMR (CDCl ₃ ): δ = 19.7, 19.8, 22.6, 22.7, 24.5, 24.79, 24.80, 28.0, 32.78, 32.80 , 37.3, 37.39, 37.41, 37.5, 39.4

The figure which shows the reaction path | route of an Example.

Claims (7)

Step 1 for derivatizing 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol to 3,7,11-trimethyl-dodeca-2,6,10-trienal;
Derivation of 3,7,11-trimethyl-dodeca-2,6,10-trienal obtained in step 1 to 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol Step 2 to perform,
2,6,10,14-Tetramethyl-pentadeca-5,9,13-trien-4-ol obtained in Step 2 was converted to 2,6,10,14-tetramethyl-pentadeca-2,6,10, Step 3 leading to 12-tetraene;
Step 4 for derivatizing 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene obtained in Step 3 to pristane;
Chemical synthesis of pristane, including   The chemical synthesis method of pristane according to claim 1, wherein the step 1 is carried out by oxidation of 3,7,11-trimethyl-dodeca-2,6,10-trien-1-ol using manganese dioxide.   The chemical synthesis method of pristane according to claim 1 or 2, wherein the step 2 is carried out by a reaction between a Grignard reagent having an isobutyl group and 3,7,11-trimethyl-dodeca-2,6,10-trienal.   4. The process of claim 1 wherein the step 3 is carried out by reaction of 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol with paratoluenesulfonic acid monohydrate. A chemical synthesis method of pristane according to any one of the above.   The pristane according to claim 4, wherein 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol and paratoluenesulfonic acid monohydrate are reacted while being gradually mixed. Chemical synthesis method.   React 2,6,10,14-tetramethyl-pentadeca-5,9,13-trien-4-ol with p-toluenesulfonic acid monohydrate using one of a micromixer and a microreactor The method for chemically synthesizing pristane according to claim 5.   7. The process according to any one of claims 1 to 6, wherein said step 4 is carried out by hydrogenation of 2,6,10,14-tetramethyl-pentadeca-2,6,10,12-tetraene in the presence of palladium on carbon. A chemical synthesis method of pristane as described.

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