JP2009073831A - Farnesol derivative and production method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a farnesol derivative that is solid at room temperature, because of its high melting temperature, highly soluble in water, and can exhibit the useful action of fanesol in vivo. <P>SOLUTION: The farnesol carboxylate derivative is represented by general formula (1) (where R<SP>1</SP>means a carboxylate residue bearing a nitrogen-substituted group). The farnesol carboxylate derivative can be produced by the esterification reaction between an amino acid bearing a protective group protecting amino, hydroxy, thiol groups or the like and farnesol; or N,N-dialkyl amino acid hydrohalide is used to carry out esterification reaction with farnesol in the presence of an activated esterification reagent. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a farnesol derivative and a method for producing the same, particularly to solidification and improvement of water solubility.

  Farnesol is a kind of sesquiterpene having three isoprenes, is a colorless liquid contained in essential oils of rose, lemongrass and citronella, is not soluble in water at all, and is a volatile compound. Farnesol is used as a fragrance and a skin protective agent, and as a pharmaceutical, excellent effects such as an antihyperlipidemic effect, an antibacterial effect against fungi, and a protective effect against oxidative damage are expected.

However, farnesol is a volatile compound that is liquid and does not dissolve in water at all. For this reason, a solubilization method by adding a large amount of a nonionic surfactant is considered for the preparation of a water-soluble preparation of farnesol or an aqueous cosmetic, but a large amount of the surfactant causes serious problems such as anaphylactic shock. May occur.
Accordingly, there is a need for a derivative that has a high melting point, is solid at room temperature, and at the same time has high water solubility, and can exhibit the useful action of farnesol in vivo.

  The present invention has been made in view of the above-described technical problems, and its purpose is to provide a derivative that has a high melting point and is solid at room temperature, and at the same time has high water solubility, and can exhibit a useful action of farnesol in vivo. Is to provide.

As a result of intensive studies by the present inventors in order to achieve the above object, a specific farnesol carboxylic acid ester derivative has a high melting point and is solid at room temperature, has excellent water solubility, It has been found that a useful action can be exhibited, and the present invention has been completed.
That is, the farnesol carboxylic acid ester derivative according to the present invention has the following general formula (1):

（式中、Ｒ^１は窒素置換基を有するカルボン酸残基を意味する。）
で表されることを特徴とする。

(In the formula, R ¹ means a carboxylic acid residue having a nitrogen substituent.)
It is represented by.

  In the present invention, the carboxylic acid residue having a nitrogen substituent is an amino acid, an N-acylamino acid, an N-alkylamino acid, an N, N-dialkylamino acid, a pyridinecarboxylic acid, or a physiologically acceptable halogenated thereof. There is provided a farnesol carboxylic acid ester derivative characterized in that it is selected from the group consisting of residues of hydrogenate, alkylsulfonate, and acidic sugar salt.

Further, the method for producing a farnesol carboxylate derivative according to the present invention protects the amino group, hydroxyl group and thiol group of an amino acid having a primary or secondary amino group or a side chain with a hydroxyl group or a thiol group with a protecting group. The protective group-binding amino acid and farnesol are esterified.
Another method for producing a farnesol carboxylic acid ester derivative according to the present invention is characterized in that an esterification reaction with farnesol is performed in the presence of an active esterification reagent using a hydrohalide salt of an N, N-dialkylamino acid. And

In addition, the farnesol derivative represented by the general formula (1) includes trans of a hydrogen atom at the 2-position and a methyl group at the 3-position of the farnesyl group (— [CH ₂ CH═CH (CH ₃ ) CH ₂ ] ₃ —H). Isomers and cis isomers, hydrogens at the 6-position and trans isomers and cis-isomers at the 7-position methyl group exist, but the present invention includes these isomers (ie, (2E, 6E) isomer, (2E, 6Z) isomer, 2Z, 6E), (2Z, 6Z), and mixtures thereof).

  According to the present invention, there is provided a farnesol carboxylic acid ester derivative that has a high melting point, is solid at room temperature, has excellent water solubility, and can exhibit the useful action of farnesol in vivo. The farnesol carboxylate derivative according to the present invention has not only a preventive effect in ischemic acute administration but also inflammation caused by ischemia or ischemia in therapeutic administration in the subacute phase and chronic phase after ischemia-reperfusion. It is possible to exert a therapeutic effect on diseases in which a sex substance is involved in onset or hatred.

Hereinafter, preferred embodiments of the present invention will be described.
The present invention relates to a farnesol carboxylic acid ester derivative represented by the following general formula (1) and a method for producing the same.

（式中、Ｒ^１は窒素置換基を有するカルボン酸残基を意味する。）

(In the formula, R ¹ means a carboxylic acid residue having a nitrogen substituent.)

Preferred examples of carboxylic acid residues having a nitrogen substituent of R ¹ include amino acids, N-acyl amino acids, N-alkyl amino acids, N, N-dialkyl amino acids, pyridine carboxylic acids and their physiologically acceptable halogens. Examples thereof include those selected from the group consisting of residues of hydrofluoric acid salts, alkylsulfonic acid salts, and acidic sugar salts.
In the present invention, “carboxylic acid residue” means a residue obtained by removing an OH group from a carboxyl group (COOH) of a carboxylic acid.

  In the carboxylic acid residue having a nitrogen substituent, the alkyl group of the alkyl-substituted amino group is a linear or branched alkyl group having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, or an n-pentyl group. Group, n-hexyl group, isopropyl group, isobutyl group, 1-methylpropyl group, tert-butyl group, 1-ethylpropyl group, isoamyl group and the like can be exemplified, and methyl group and ethyl group are particularly preferable. . The acyl group of the acyl-substituted amino group is preferably an acyl group in which a linear or branched alkyl group having 1 to 6 carbon atoms is a hydrocarbon chain, and specific examples of the alkyl group moiety are as described above.

  The amino group and the carbonyl group are preferably bonded with a linear, branched or cyclic alkylene group having 1 to 6 carbon atoms. The branched alkylene group means an alkylene group derived from an alkyl group such as isopropyl group, isobutyl group, 1-methylpropyl group, tert-butyl group, and 1-ethylpropyl group. The cyclic alkylene group means an alkylene group containing a cyclopentane ring, a cyclohexane ring, a methylcyclohexane ring or the like in the structure. Particularly preferred as the alkylene group is a methylene group or an ethylene group.

  The nitrogen substituent in the carboxylic acid residue having a nitrogen substituent may form a salt. For example, as the hydrohalide, hydrochloride, hydrobromide and the like are preferable. In the present invention, the hydrohalide salt has an advantage that the melting point is higher than that of the original farnesol, and it is easy to handle the preparation. Examples of the alkyl sulfonate include methane sulfonate. Examples of the saccharide salt include gluconate, glucoheptanoate, and lactobionate.

Next, examples of the method for producing the farnesol carboxylic acid ester derivative according to the present invention include the following methods.
By carrying out an esterification reaction by a conventional method with farnesol represented by the following general formula (2) and a carboxylic acid having a nitrogen substituent, or a reactive acid derivative thereof, or a hydrohalide thereof. The farnesol carboxylic acid ester (1) of the invention can be obtained. The stereoisomerism of the farnesyl group in the general formula (2) is as described in the general formula (1).

  The esterification reaction of farnesol follows a conventional method. When esterification is performed using a primary or secondary amino group, or an amino acid having a hydroxyl group or a thiol group in the side chain, a tert-butoxycarbonyl group (hereinafter t-BOC) is used. These primary or secondary amino groups, hydroxyl groups, and thiol groups are preferably protected and used with an appropriate protective group such as a benzyloxycarbonyl group (hereinafter abbreviated as Z group).

In addition, N, N-dialkylamino acids use hydrohalides, and are used for active esterification reagents such as dicyclohexylcarbodiimide (hereinafter abbreviated as DCC) and N, N-disuccinimide oxalate (hereinafter abbreviated as DSO). The reaction is preferably carried out in the presence. In this case, anhydrous pyridine is preferred as the solvent.
In the method using a reactive acid derivative, a method using acid halogenite, particularly acid chloride is preferable. In this case, an anhydrous benzene / anhydrous pyridine mixture is preferred as the solvent.

Hydrohalides, alkylsulfonates, and acidic sugar salts are produced by reacting free amino acid esters with lactones of hydrohalic acid, alkylsulfonic acid, and acidic sugar by a conventional method. Further, after the N-acylamino acid ester is produced, a hydrohalide can be produced by deprotection with hydrohalic acid by a conventional method.
The hydrohalic acid salt of farnesol carboxylic acid ester (1) of the present invention is a crystalline powder having a high melting point, is easy and simple to handle in formulation technology, and has high water solubility. Therefore, it is useful for preparations that can be administered intravenously, eye drops, oral preparations, aqueous coating agents, sprays, and the like.

  Hereinafter, preferred embodiments of the present invention will be described. The scope of the present invention is not limited to the following examples.

Manufacturing method A
Add N, N-dialkylamino acid hydrochloride (3.1 mmol), DCC (3.1 mmol) and anhydrous pyridine (30 ml), stir for 30 minutes, add farnesol (3.1 mmol), and stir at room temperature for 16 hours. The solvent is distilled off under reduced pressure, the residue is suspended in distilled water, and the soluble fraction is extracted with ethyl acetate. The extract is dehydrated with anhydrous sodium sulfate, the solvent is distilled off under reduced pressure, and the residue is separated and purified by silica gel flash chromatography (eluent: n-hexane: ethyl acetate) to obtain N, N-dialkylamino acid farnesol ester.

Manufacturing method B
Dissolve N, N-dialkylamino acid farnesol ester in a small amount of acetone, add 2-fold molar amount of hydrochloric acid-dioxane, distill off the solvent under reduced pressure, recrystallize the residue with acetone, and N, N-dialkylamino acid farnesol ester To obtain the hydrochloride salt of

Manufacturing method C
Dissolve 0.1 mol of amino acid in 100 ml of distilled water-dioxane (1: 1, v / v), add 30 ml of triethylamine, gradually add di-tert-butyl dicarbonate and stir for 30 minutes at room temperature. Dioxane is distilled off under reduced pressure, 50 ml of aqueous sodium hydrogen carbonate solution (0.5 M) is added, and the mixture is washed with 100 ml of ethyl acetate. The ethyl acetate layer was washed with 50 ml of sodium bicarbonate solution, and the aqueous layers were combined and acidified (pH 3) with an aqueous citric acid solution (0.5 M) under ice-cooling. After saturating sodium chloride, ethyl acetate was added. Extract with (100 ml x 3 times). The extract is dehydrated with anhydrous sodium sulfate, and the solvent is distilled off under reduced pressure. Isopropyl ether is added to the oily residue or it is crystallized by cooling to obtain an Nt-BOC amino acid.

  Farnesol 5 mmol, N-t-BOC amino acid 5 mmol, and DCC 5 mmol are added to 30 ml of anhydrous pyridine and stirred at room temperature for 20 hours. The solvent is distilled off under reduced pressure, and ethyl acetate is added to the residue to extract a soluble fraction (100 ml x 2 times). The extract is concentrated under reduced pressure, and the residue is separated and purified by silica gel column chromatography (eluent: n-hexane-ethyl acetate) to obtain farnesol Nt-BOC-amino acid ester.

  Dissolve farnesol Nt-BOC-amino acid ester in a small amount of acetone, add hydrochloric acid-dioxane (2.5-4.0 N) in an amount equivalent to 20 times the molar amount of hydrochloric acid and stir for 1 hour, and then evaporate the solvent under reduced pressure. To do. The residue is recrystallized with acetone-methanol system or ethyl acetate-methanol system to obtain farnesol amino acid ester hydrochloride.

  3 mmol of farnesol amino acid ester hydrochloride is added to 150 ml of water, sodium bicarbonate is added to bring the pH of the solution to 7-8, and then extracted with ethyl acetate (100 ml x 3 times). The extract is dehydrated with anhydrous sodium sulfate, and then the solvent is distilled off under reduced pressure to obtain oily farnesol amino acid ester.

Inhibition of ischemia-reperfusion cerebral injury Cerebral infarction is caused by various damage mechanisms caused by a decrease in cerebral blood flow in the domino manner, and the brain damage progresses from ischemic center to the ischemic periphery. In particular, it is strongly related to oxidative stress and inflammatory reaction after onset, and considering the seriousness and QOL, treatment in the subacute phase and chronic phase after onset is extremely important. Clinically, a drug capable of suppressing ischemia-reperfusion injury even after the start of administration after cerebral infarction is desired.

  There are very few therapeutic agents after the onset of cerebral infarction, and there are no therapeutic agents in particular in the subacute phase and chronic phase after the onset. At present, the thrombolytic agent tissue plasminogen activator (tPA) and the hydroxy radical scavenger edaravone are examples of treatments for acute cerebral infarction that improve the central part of ischemia caused by decreased cerebral blood flow. And serious side effects such as renal failure. That is, there is a demand for the development of an excellent therapeutic agent for subacute and chronic ischemic cerebrovascular disorders with sufficient time to start treatment after the onset of cerebral infarction.

From this, ischemia reflecting the process leading to the direct damage of reactive oxygen species (ROIs) due to reperfusion and secondary oxidative stress and inflammatory response due to ROIs by drug administration after reperfusion in the MCA occlusion model A therapeutic effect evaluation model for reperfusion brain injury was constructed, and the effect of the test compound as a therapeutic agent was examined.
In the MCA occlusion model, the drug was administered immediately before and during the infarction, and the effect as a prophylactic agent was also examined.

(1) Evaluation method for prevention of ischemia-reperfusion brain injury
Middle cerebral artery (MCA) occlusion model mice were prepared using 25-30 g (6-7 weeks old) ddY male mice according to the method of Koizumi et al. (Stroke, Vol. 8, 1-8, 1986). The occlusion was 4 hours, and the test drug solution was intravenously administered twice, immediately before the start of infarction and 3 hours of infarction. A brain slice specimen 24 hours after the start of the infarction was prepared, and after triphenyltetrazolium chloride staining (TTC steining), the brain infarct volume was measured by image processing from the brain slice specimen.

(2) Evaluation method for therapeutic effect of ischemia-reperfusion brain injury
Middle cerebral artery (MCA) occlusion model mice were prepared using 25-30 g (6-7 weeks old) ddY male mice according to the method of Koizumi et al. (Stroke, Vol. 8, 1-8, 1986). The occlusion was 4 hours, and the drug solution was administered intravenously once 6 hours or 10 hours after initiation of ischemia (2 hours or 4 hours after reperfusion). A brain slice sample 24 hours after the start of occlusion was prepared, and after triphenyltetrazolium chloride staining (TTC steining), the brain infarct volume was measured from the brain slice sample by image processing.

Preventive effect of farnesol (FO) and farnesol N, N-dimethylglycine ester hydrochloride (FODMG) on ischemia-reperfusion brain injury According to the above-mentioned prevention evaluation method for ischemia-reperfusion brain injury (2E, 6E) And (2E, 6E) farnesol N, N-dimethylglycinate hydrochloride (FODMG) and the commercial preparation edaravone on blood reperfusion brain injury were evaluated.
FIG. 1 shows the brain section sample 24 hours after the occlusion of the MCA occlusion mouse, and FIG. 2 shows the volume of the infarct lesion 24 hours after the start of the occlusion obtained from the brain section sample 24 hours after the occlusion of the MCA occlusion mouse. FO was dissolved in DMSO and administered intravenously, and FODMG was dissolved in water and administered intravenously.

FO showed no significant suppression of infarct volume at 2 μmol / kg × 2 administration, but significantly suppressed infarct volume at a dose of 20 μmol / kg × 2.
FODMG significantly suppressed infarct volume at both doses of 2 μmol / kg × 2 and 20 μmol / kg × 2, and the effect was dependent on the dose. FODMG showed an excellent preventive effect on blood reperfusion brain injury compared with FO.
On the other hand, edaravone was significantly suppressed by administration of 2 μmol / kg x 2, but no significant effect was seen at the dose of 20 μmol / kg x 2, and no effective effect was seen at higher doses. The range of was shown to be narrow.
Since the effect of FODMG depends on the dose, it is clear that the effective dose range is wide and superior to edaravone.

Therapeutic effect of farnesol N, N-dimethylglycine ester hydrochloride (FODMG) on ischemia-reperfusion brain injury According to the above-mentioned method for evaluating the therapeutic effect of ischemia-reperfusion brain injury, a dose (20 μmol / kg) that is not effective with edaravone The therapeutic effect of FODMG on ischemia-reperfusion brain injury was evaluated by single administration 6 hours or 10 hours after the onset of ischemia. FO was dissolved in DMSO and administered intravenously, and FODMG was dissolved in water and administered intravenously.
FODMG significantly suppressed the infarct volume in both single administration at 6 hours and 10 hours after the onset of ischemia (FIG. 3). It is clear that FODMG can be administered intravenously and can extend the treatment start time after the onset of cerebral infarction extremely long.

It is explanatory drawing of the preventive effect of ischemic brain injury by the farnesol derivative concerning this invention. It is explanatory drawing of the preventive effect of ischemic brain injury by the farnesol derivative concerning this invention. It is explanatory drawing of the therapeutic effect of ischemic brain injury by the farnesol derivative concerning this invention.

Claims (4)

The following general formula (1):

(Wherein R ¹ represents a carboxylic acid residue having a nitrogen substituent).   The derivative according to claim 1, wherein the carboxylic acid residue having a nitrogen substituent is an amino acid, an N-acylamino acid, an N-alkylamino acid, an N, N-dialkylamino acid, a pyridinecarboxylic acid, or a physiologically acceptable product thereof. A farnesol carboxylate derivative characterized by being selected from the group consisting of residues of hydrohalides, alkylsulfonates, and acidic sugar salts.   Protecting the amino group, hydroxyl group and thiol group of a primary or secondary amino group or an amino acid having a hydroxyl group or a thiol group in a side chain with a protecting group, and esterifying the protecting group-bound amino acid with farnesol. The method for producing a farnesol carboxylic acid ester derivative according to claim 1 or 2, wherein   3. The method for producing a farnesol carboxylic acid ester derivative according to claim 1 or 2, wherein an esterification reaction is performed with farnesol in the presence of an active esterification reagent using a hydrohalide salt of an N, N-dialkylamino acid. .

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