JPH0220617B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to dihydropolyprenylcarboxylic acids and esters thereof. More specifically, the present invention relates to the general formula (In the formula, [formula] represents a trans isoprene unit,
[Formula] represents a cis isoprene unit, n represents an integer from 11 to 19, and R represents a lower alkyl group or a hydrogen atom. ). The dihydropolyprenylcarboxylic acid represented by the general formula (I) and its ester provided by the present invention are useful substances as raw materials for pharmaceuticals, cosmetics, etc., and are particularly useful as synthesis intermediates of mammalian dolichols. . Dolichols were first isolated from pig liver etc. by JFPennock et al. in 1960 [see Nature (London), 186, 470 (1960)], and were later given the general formula (A). [In the formula, [formula] represents a trans isoprene unit,
[Formula] represents a cis isoprene unit. The same shall apply hereinafter in this specification. ] is a mixture of polyprenol homologs having the structure shown in formula (A), where j representing the number of cis isoprene units generally ranges from 12 to 18, and j=
It was revealed that three homologs 14, 15 and 16 were the main constituents [RWKeenan et al.,
See Biochemical Journal, 165, 505 (1977)].
Dolichols are widely distributed not only in the liver of pigs but also in the bodies of mammals, and are known to play extremely important functions in maintaining the life of living organisms. For example, JB Harford et al. conducted an in vitro study using the white medulla of calves and pigs' brains, and found that exogenous dolichol promotes the incorporation of sugar components such as mannose into lipids, which are important for maintaining the life of living organisms. [Biochmical and
Biophysical Research Communication, 76,
1036 (1977)]. The effect of dolichols on promoting the incorporation of sugar components into lipids is more pronounced in animals that have already matured than in animals that are still in the growing stage, so the role of dolichols in preventing aging is attracting attention. Also, RW Keenan
[Archives of
Biochemistry and Biophysics, 179, 634 (1977)
reference〕. Furthermore, Akamatsu et al. quantified dolichol phosphate ester in the regenerated liver of rats and found that the amount was significantly reduced compared to that in the normal liver, indicating that the glycoprotein synthesis function in the liver tissue was greatly reduced. We found that the function was improved by externally adding dolichol phosphate [presented at the 54th Annual Meeting of the Japanese Biochemical Society (1981)]. As mentioned above, dolichols are substances that control extremely important functions for living organisms, and are useful as pharmaceuticals or intermediates thereof. Only 0.6 g of dolichol can be obtained through this process [J. Burgos et al., Biochemical
See Journal, 88, 470 (1963)]. Total synthesis of dolichols is extremely difficult using current organic synthesis techniques, as is clear from their complex and unique molecular structures. It would be advantageous if dolichols could be obtained by relying on natural products as synthetic intermediates and adding simple synthetic chemical treatments to them, but such convenient substances have not been found so far. Conventionally, the following general formula (B) [However, it is known that polyprenols represented by k = 4 to 6 (these are called betulaprenols) can be collected from silver birch ( Betula verrucosa ), but from these polyprenols, cis-isoprene units It is almost impossible to synthesize dolichols mainly containing 14, 15, and 16 molecules using current organic synthesis techniques. Also,
K. Hannus et al .
reported that a polyprenyl component was isolated from leaves of S. sylvestris at a yield of 1% on a dry weight basis, and that this component was a polyprenyl acetate mixture containing 10 to 19 isoprene units primarily in the cis configuration. Phytochemistry, 13, 2563 (1974)], their report does not elucidate the details of the trans and cis configurations in the polyprenyl acetate. Furthermore, DFZinkel et al. reported the presence of C ₉₀ polyprenols with 18 isoprene units or an average number of isoprene units in extracts of leaves of pine strobus ( Pinus strobus ). Phytochemistry, 11,
3387 (1972)], this report does not provide a detailed analysis of the trans and cis configurations of the polyprenol. Some of the present inventors and their co-researchers first hydrolyzed the extracts extracted from Japanese staghorn and Himalayan cedar using organic solvents, if necessary, and then used chromatography, fractional dissolution, and other methods. By processing by suitable separation methods, 14
A polyprenyl fraction consisting of a polyprenol and/or a mixture of its acetate homologues having ~22 isoprene units in exactly the same trans, cis configuration as mammalian dolichols is obtained; exhibiting a distribution of polyprenyl congeners very similar to the distribution of polyprenyl congeners in mammalian dolichols, only in the absence of α-terminal saturated isoprene units, of which the polyprenyl fraction is optionally a constituent; It can be relatively easily separated into individual polyprenyl analogues (with a uniform number of isoprene units), and therefore the polyprenyl fraction and each polyprenyl analogue separated therefrom can be used as synthetic intermediates for mammalian dolichols. I found it to be very suitable. In order to efficiently produce mammalian dolichols using the above-mentioned polyprenyl compounds, the present inventors have intensively investigated a method of introducing a saturated isoprene unit into the α-terminus of the polyprenyl chain of the polyprenyl compound, and found that such a method The present invention was completed by creating a dihydropolyprenylcarboxylic acid represented by the general formula (I) and an ester thereof, which are useful as intermediates in the above-described general formula (I). The dihydropolyprenylcarboxylic acid of the present invention in which R is a hydrogen atom in the general formula (I) [hereinafter referred to as dihydropolyprenylcarboxylic acid (I)]. ]
is a general formula (In the formula, n is as defined above.) Polyprenylcarboxylic acid [hereinafter referred to as polyprenylcarboxylic acid ()]. ] is reacted with hydrogen (H ₂ ) in the presence of a hydrogenation catalyst to selectively hydrogenate the carbon-carbon double bond on the terminal side of the carboxylic acid, or reduced using lithium in liquid ammonia [Birch ( Birch) reduction]. Further, the dihydropolyprenylcarboxylic acid ester of the present invention in which R in the general formula (I) is a lower alkyl group can be produced by esterifying the dihydropolyprenylcarboxylic acid of the present invention described above. When carrying out the above hydrogenation reaction, it is not preferable to use too extreme hydrogenation conditions because double bonds other than the target carbon-carbon double bond on the terminal side of the carboxylic acid will also be hydrogenated. Of course, it is not preferable to use conditions that are too secret because the desired reaction may not proceed at all or the reaction may take too long to complete. From the above viewpoint, it is important to set reaction conditions for suitably carrying out the hydrogenation reaction. Here, metals such as rhodium, palladium, and nickel, or compounds thereof can be used as the hydrogenation catalyst, but it is particularly preferable to use a rhodium complex compound. Examples of specifically used rhodium complex compounds include RhCl [P(C ₆ H ₅ ) ₃ ] ₃ and HRhCl ₂ [P
(C ₆ H ₅ ) ₃ ] ₃ , Rh ₂ (1,5-cyclooctadiene)
Examples include complex compounds prepared from ₂ Cl ₂ and menthyldiphenylphosphine or neomenthyldiphenylphosphine. When an optically active ligand is used, optically active dihydropolyprenylcarboxylic acid (I) can be produced. The amount of the hydrogenation catalyst used is suitably in the range of 0.0001 to 0.5 molar equivalent, preferably 0.001 to 0.1 molar equivalent, based on the polyprenylcarboxylic acid (). Solvents used in the hydrogenation reaction include alcoholic solvents such as methanol or ethanol, which are heated after adding magnesium or treated with hydrogen in the coexistence of Raney nickel, and then distilled, or benzene or toluene, which is distilled in the coexistence of sodium and benzophenone. Hydrocarbon solvents are preferred. The amount of solvent used is not critical, but
5 to 100 for polyprenylcarboxylic acid ()
Weight times, preferably in the range of 10 to 50 times weight, are suitable. The hydrogen pressure, reaction temperature, and reaction time when carrying out the hydrogenation reaction vary depending on the equipment used, but are usually 1 to 30 atmospheres and 10 to 60 degrees Celsius, respectively.
and 6 to 72 hours is preferred. In addition, during this hydrogenation reaction, basic compounds such as sodium methoxide and triethylamine are added to polyprenylcarboxylic acid () at a rate of 0.01~
The coexistence of 0.5 equivalent mole is preferable because the hydrogenation reaction is significantly accelerated. After the hydrogenation reaction, the reaction solution is made acidic by adding dilute hydrochloric acid or dilute sulfuric acid, extracted using a solvent such as hexane, pentane, benzene, diethyl ether, etc., and dihydropolyprenylcarboxylic acid is obtained by distilling off the solvent from the extract. Acid (I) is obtained. Alternatively, when reducing polyprenyl carboxylic acid () by the Birch reduction method, the objective can be achieved by adding polyprenyl carboxylic acid () to liquid ammonia in which lithium is dissolved. can. The amount of lithium used is 1 to 1 per polyprenylcarboxylic acid ()
100 equivalents, preferably 2 to 10 equivalents. The amount of liquid ammonia used is not critical, but it is 5 to 100 times the weight of polyprenylcarboxylic acid ().
Preferably, the range is 10 to 50 times the weight. When adding polyprenylcarboxylic acid (), it is preferable to add it in the form of a solution dissolved in anhydrous diethyl ether or anhydrous tetrahydrofuran for convenience and to improve the uniformity of the reactant. It is preferable to carry out this Birch reduction reaction at the boiling point of liquid ammonia (approximately -33°C), but if necessary, the reaction may also be carried out at a temperature higher than the boiling point and under pressure using further low-temperature cooling or using a pressure-resistant device. It is possible. After continuing stirring at the above reaction temperature for about 0.5 to 10 hours, for example, ammonium chloride is added to the reaction solution to decompose excess lithium, and then ammonia is distilled off to obtain a crude product of dihydropolyprenylcarboxylic acid (I). can be obtained. Purification of dihydropolyprenylcarboxylic acid (I) can be carried out by applying conventionally known separation and purification techniques. Chromatography is particularly preferred because it is simple. Adsorbents that can be used in this chromatography include silica gel, alumina, activated carbon, florisil, and cellulose, with silica gel being particularly preferred. As the developing solvent, use a mixture of a hydrocarbon solvent such as hexane, pentane, petroleum ether, benzene, etc. and a small amount of a polar solvent such as chloroform, methylene chloride, diethyl ether, diisopropyl ether, methyl acetate, ethyl acetate, or acetone. is preferable. Dihydropolyprenylcarboxylic acid (I) for obtaining a dihydropolyprenylcarboxylic acid ester in which R is a lower alkyl group in general formula (I)
The esterification reaction can be carried out by applying a known method conventionally used for esterification of higher fatty acids. For example, the objective can be achieved by dissolving the dihydropolyprenylcarboxylic acid (I) in a solution in which dry hydrogen chloride gas is blown into a lower alcohol, and continuing stirring at room temperature or at a temperature below the boiling point of the solvent. can. In addition, in order to synthesize the methyl ester of dihydropolyprenylcarboxylic acid (I), the dihydropolyprenylcarboxylic acid (I) is dissolved in a solvent such as anhydrous diethyl ether or anhydrous tetrahydrofuran, and diethyl ether of diazomethane is dissolved therein. The purpose can also be achieved by adding a solution and reacting. These lower alkyl esters of dihydropolyprenylcarboxylic acid (I) can be purified using substantially the same method as in the case of purifying the dihydropolyprenylcarboxylic acid (I) itself described above. In addition, general formula (I)
When R is a lower alkyl group, examples of the lower alkyl group include methyl group, ethyl group, n
-propyl group, isopropyl group, n-butyl group,
Isobutyl group, t-butyl group, n-pentyl group,
Examples include neopentyl group and n-hexyl group. The polyprenylcarboxylic acid () subjected to the hydrogenation reaction has the general formula (In the formula, n is as defined above.) Polyprenylacetone [hereinafter referred to as polyprenylacetone ()]. ] as a general formula (In the formula, R ¹ and R ² represent the same or different lower alkyl groups.) A general formula obtained by Wittig reaction with a compound represented by (In the formula, n and R ¹ are as defined above.)
A polyprenylcarboxylic acid ester represented by [hereinafter referred to as polyprenylcarboxylic acid ester (V)]. ] can be produced by hydrolyzing. The above Witzig reaction is usually performed in a solvent. Examples of suitably used solvents include dimethylformamide, tetrahydrofuran, and diethyl ether. In order to allow the desired reaction to proceed smoothly, it is preferable that the solvent used be sufficiently dried to an anhydrous state. Further, from the same viewpoint, it is desirable to replace the reaction system with an inert gas such as nitrogen or argon. The amount of solvent used is polyprenylacetone ()
5 to 50 times the amount by weight is suitable. Among the compounds represented by the above general formula (), the following compounds are particularly preferably used as reagents for carrying out the Witzig reaction. When carrying out the Witzig reaction, it is necessary to form a phosphorylide by treating the Witchig reagent as described above with a basic compound. Examples of the basic compound used for this purpose include n.
Preferred examples include -butyllithium, methyllithium, sodium hydride, potassium hydride, sodium methoxide, and sodium ethoxide. After adding these basic compounds to the above-mentioned solvent, -30℃ to +80℃, preferably -10℃
A phosphorylide can be formed by adding the Witzig reagent to the mixture while stirring at a temperature of 0.degree. C. to +50.degree. C. and continuing stirring at a temperature in the above range for about 0.5 to 24 hours. The amount of the basic compound used in this case is preferably about 0.5 to 1.5 molar equivalents based on the Witzig reagent. By adding polyprenylacetone () to the phosphorylide solution prepared in this way and reacting at about 0°C to 100°C, preferably 15°C to 18°C, more preferably 20°C to 50°C, polyprenylcarboxylic acid Ester (V) can be obtained. The reaction time required to complete this reaction is generally about 0.5~
Within 24 hours. The amount of Witzig reagent used is 0.5 to polyprenylacetone ()
10.0 molar equivalents, preferably 0.8 to 8.0 molar equivalents, more preferably 1.0 to 5.0 molar equivalents. Polyprenylcarboxylic acid (V) can be obtained by hydrolyzing the polyprenylcarboxylic acid ester (V) synthesized as described above in accordance with the method applied to the hydrolysis reaction of ordinary fatty acid esters. For example, by stirring polyprenylcarboxylic acid ester (V) in aqueous ethanol together with sodium hydroxide in an amount of about 2 to 5 times the molar equivalent of the ester under reflux conditions for about 1 to 5 hours, it is possible to obtain polypropylene with good yield. Prenylcarboxylic acid () can be obtained. Polyprenylcarboxylic acid () and its esters can be purified by various methods based on known separation and purification methods, but purification by chromatography is particularly convenient. Adsorbents used in this chromatography include silica gel, alumina, activated carbon, florisil, cellulose, and the like, with silica gel being particularly preferred. Examples of developing solvents include hydrocarbon solvents such as hexane, pentane, petroleum ether, benzene, and toluene mixed with a small amount of polar solvents such as chloroform, methylene chloride, diethyl ether, diisopropyl ether, methyl acetate, ethyl acetate, and acetone. It is preferable to use The polyprenylacetone () used in the above reaction has the general formula (In the formula, n is as defined above, and X represents a halogen atom.) Polyprenyl halide (hereinafter referred to as polyprenyl halide ()) represented by the formula (In the formula, R ³ represents a lower alkyl group.) Acetoacetate [hereinafter referred to as acetoacetate ()]. ] General formula obtained by reacting with (In the formula, n and R ₃ are as defined above.) Polyprenylketocarboxylic acid ester [hereinafter referred to as polyprenylketocarboxylic acid ester ()]. ) can be obtained by hydrolyzing and decarboxylating. As mentioned above, polyprenyl halide () has the general formula that can be obtained directly from extracts of Japanese yam or Himalayan cedar or through hydrolysis. (In the formula, n is as defined above.) Polyprenol or a mixture thereof is treated with a halogenating agent such as phosphorus trihalide such as PCl ₃ or PBr ₃ or thionyl halide such as SCCl ₂ or SOBr ₂ to generate a halogen. It can be easily obtained by This halogenation reaction is usually carried out by dissolving the above-mentioned polyprenol in a suitable solvent such as hexane or diethyl ether, and heating the solution at about -20°C in the presence or absence of a base such as triethylamine or pyridine. This is done by adding a halogenating agent at a temperature of ~+50°C. The reaction between polyprenyl halide () and acetoacetate () is preferably carried out in a solvent. Suitable solvents include ether solvents such as diethyl ether, tetrahydrofuran, dioxane, and dimethoxyethane. The amount of the solvent used is not critical, but is 2 to 100 times (by weight), preferably 5 to 80 times (by weight), and more preferably 10 to 50 times (by weight) to the polyprenyl halide (). . It is preferable to use a sufficiently dried solvent in order to allow the intended reaction to proceed smoothly. In order to carry out this reaction, the presence of a basic compound is essential. The basic compounds used include alkali metal hydrides such as sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, sodium t-butoxide, potassium t-butoxide, sodium methoxide, and sodium ethoxide;
Hydroxides or alkoxides, n-butyllithium, methyllithium, etc. are suitable. The basic compound is generally about 0.1 to 5.0 mol, preferably 0.5 to 3.0 mol per mol of acetoacetate ().
It is used in a molar ratio, more preferably 0.7 to 1.5 molar. In a preferred embodiment, the acetoacetate () is added to a solution or dispersion of the basic compound, or conversely, the basic compound is added all at once or gradually in small portions to a solution of the acetoacetate (). An anion of acetoacetate () is formed, and then polyprenyl halide () is added thereto and reacted. The ratio of acetoacetate () and polyprenyl halide () to be used is not critical, but the molar ratio of acetoacetate ()/polyprenyl halide () is from 1/2 to
The ratio is 20/1, preferably 4/5 to 10/1, and more preferably 1/1 to 5/1. When forming the anion of acetoacetate (), the temperature is -30°C ~ under an inert gas atmosphere such as nitrogen gas or argon.
It is desirable to carry out the reaction at a temperature of +100°C, preferably -10°C to +80°C, so that the desired anion can be smoothly formed while suppressing side reactions. The time required for this anion formation varies depending on the reaction temperature used, but usually about 10 minutes to 5 hours is sufficient. Polyprenyl halide () is added to the anionic solution of acetoacetate () prepared in this manner and reacted. Depending on the reaction conditions used, the reaction may proceed more smoothly by adding polyprenyl halide (2) in small portions or in a dropwise manner rather than adding the entire amount at once. The temperature within the reaction system during the time of addition of polyprenyl halide () and thereafter until completion of the reaction is not critical, but is preferably within the range of -10°C to the boiling point of the solvent used. If the reaction temperature is too low, the reaction progresses slowly and takes too much time to complete the reaction. On the other hand, if the reaction temperature is too high, undesirable side reactions will proceed. From this point of view, it is preferable to employ a reaction temperature within the range of 0°C to 80°C. Polyprenyl halide ()
In order to complete the reaction after adding , it is necessary to continue stirring the reaction mixture at the above reaction temperature, and the time required for this varies depending on the reaction temperature used, but is usually about 30 minutes to 24 hours. It is. In order to confirm the progress of the reaction, it is convenient and preferable to monitor the decrease in the raw material polyprenyl halide () by thin layer chromatography. After the reaction, isolation of the polyprenylketocarboxylic acid ester () from the reaction mixture can be easily accomplished by applying isolation methods used in conventionally known synthetic reactions. Chromatography is particularly conveniently used. Adsorbents that can be used for chromatography include silica gel, alumina,
Examples include activated carbon and cellulose. Among these, silica gel is particularly preferably used. As the developing solvent, a mixture of a small amount of a polar solvent such as diethyl ether, chloroform, ethyl acetate, or ethyl alcohol with a hydrocarbon solvent such as hexane, pentane, petroleum ether, or benzene is suitable. In addition, this isolation step is omitted and the next step, the synthesis reaction of polyprenylacetone (), is carried out directly.
It is also possible to carry out a purification step thereafter. Polyprenylketocarboxylic acid ester () can be hydrolyzed by applying the method conventionally used for the hydrolysis reaction of higher fatty acid esters. . For example, the objective can be achieved by stirring polyprenylketocarboxylic acid ester () with sodium hydroxide or potassium hydroxide in aqueous methanol, aqueous ethanol or aqueous isopropanol. The amount of sodium hydroxide or potassium hydroxide used is preferably about 1.0 to 20.0 molar equivalents, preferably 1.5 to 10.0 molar equivalents, based on the polyprenyl ketocarboxylic acid ester (). Hydrous alcohols such as those mentioned above are suitable as reaction solvents, but
It is also preferable to add a small amount of a hydrocarbon solvent such as hexane, pentane, benzene, toluene, etc. to increase the solubility of the polyprenylketocarboxylic acid ester (). In order to allow the above-mentioned hydrolysis reaction to proceed smoothly, it is desirable to adopt a reaction temperature ranging from 0°C to the boiling point of the solvent used, preferably within the range of 25°C to 65°C. The time required to complete the reaction varies depending on the temperature conditions employed at this time, but is usually within a range of about 0.5 to 24 hours. After carrying out the hydrolysis reaction as described above, the reaction solution is neutralized using a mineral acid such as hydrochloric acid or sulfuric acid, preferably under room temperature conditions or ice-cooled conditions, and the reaction solution is further adjusted to a pH of 1 to 1. Under acidic conditions of about 3, a decarboxylation reaction occurs automatically and polyprenylacetone () is formed. After the decarboxylation reaction is completed,
The reaction solution is extracted with hexane, benzene, diethyl ether, etc., washed thoroughly with water, the organic layer is dried, and the solvent is distilled off to obtain crude polyprenylacetone (). Chromatography is preferably employed to produce this product.
Adsorbents used in chromatography include silica gel, alumina, activated carbon, and cellulose, with silica gel being particularly suitable. As the developing solvent, a mixture of a small amount of a polar solvent such as diethyl ether, diisopropyl ether, chloroform, ethyl acetate, methyl acetate, etc. with a hydrocarbon solvent such as hexane, pentane, petroleum ether, benzene, toluene, etc. is suitable. As mentioned above, dihydropolyprenylcarboxylic acid and its ester represented by the general formula (I) are synthesized using the polyprenylacetone () synthesized as described above as a raw material, but these compounds are similar to mammalian dolichols. Useful as a synthetic raw material. The mammalian dolichols represented by the general formula (A) can be obtained by reducing the compound represented by the general formula (I) with, for example, lithium aluminum hydride. Hereinafter, the present invention will be explained in more detail with reference to Examples and Reference Examples. In addition, IR analysis in Examples and Reference Examples was measured using a liquid film, and NMR analysis was performed using TMS.
was measured as an internal standard. The FD-MASS analysis values are values corrected as ¹ H, ¹² C, ¹⁶ O, ³⁵ Cl, and ⁷⁹ Br. Reference example 1 Separation of polyprenol 10 kg of fig leaves collected in Kurashiki City at the end of October
(undried weight) was dried with hot air at about 40°C for 24 hours, and then extracted by immersing it in chloroform 80 at room temperature (about 15°C) for one week. Petroleum ether 5 was added to the concentrate obtained by distilling off chloroform from this extract to separate insoluble components, and after concentrating the liquid, it was separated using a silica gel column using chloroform as a developing solvent to obtain about 37 g of an oily substance. Obtained. Approximately 400 ml of acetone is added to this oil to dissolve the acetone-soluble components, the resulting mixture is filtered, and the liquid is concentrated.
The obtained oil was heated at 65°C for 2 hours with 400 ml of methanol, 0 ml of water and 20 g of sodium hydroxide, then the methanol was distilled off and the residue was extracted with diethyl ether (500 ml). After washing with water five times, it was dried over anhydrous sodium sulfate, and the solvent was distilled off to obtain 24.2 g of an oily substance. Next, this oil was mixed with n-hexane/isopropyl ether = 90/10 using about 1 kg of silica gel.
(volume ratio) of the mixed solution to obtain 21.8 g of oil. This oily substance is polyprenol with a purity of 95% or more, and it was collected using a semi-preparative high-performance liquid chromatography column manufactured by Merck & Co., Ltd.
High performance liquid chromatography analysis was performed using LiChrosorbRP18-10 (C ₁₈ type) using a mixed solvent of acetone/methanol = 90/10 (volume ratio) as the eluent and a differential refractometer as a detector. The results of determining the area ratio of each peak in the chromatogram were as follows. [Table] [Table] Using this high-performance liquid chromatography, each component was separated from the above oily substance and analyzed by mass spectrometry, infrared absorption spectrum, ¹ H-NMR spectrum, and ¹³ C
- It was confirmed by NMR spectrum that these components were polyprenol having a structure represented by the general formula (). Field ionization mass spectrometry (FD-
Table 1 shows the results of MASS) and the δ value of ¹ H-NMR.
The δ values of ¹³ C-NMR are summarized in Table 2. [Table] [Table] Reference Example 2 Synthesis of polyprenyl bromide Polyprenol of general formula () where n=15
12.4 g and 1 ml of pyridine were added to 200 ml of n-hexane, and 2.0 g of phosphorus tribromide was added dropwise to the resulting solution at room temperature (approximately 20°C) under a nitrogen gas atmosphere. Stir under atmosphere overnight.
Next, this n-hexane solution was placed in a separating funnel, washed three times with about 50 ml of water, dried over anhydrous magnesium sulfate, and the n-hexane was distilled off to obtain 12.0 g of a slightly yellow liquid. When NMR analysis was performed on this product, the signal (d, δ = 4.08) assigned to the -CH ₂ OH group of the raw material polyprenol disappeared, and a new signal (d, δ = 4.08) assigned to -CH ₂ Br was generated. , δ=3.91) appeared.
Further, when this liquid material was analyzed by FD-MASS, it was found that m/e=1304. According to these analysis results, the above product has the general formula () where n=
15, it was confirmed to be polyprenyl bromide where X=Br. Polyprenyl bromides with n other than 15 were also synthesized by similar operations. Example 1 30 ml of anhydrous tetrahydrofuran in a three-necked flask
and 640 mg of 50% sodium hydride were added thereto, and 1.57 g of ethyl acetoacetate was added dropwise while stirring at room temperature. After the intense generation of hydrogen gas became calm, the temperature in the flask was gradually raised while purging the inside of the flask with nitrogen gas, and stirring was continued for 1 hour under the condition of refluxing the solvent. After cooling the reaction system to room temperature, polyprenyl bromide synthesized according to Reference Example 2 and having general formula () where n=15 and X=Br was added to the reaction system.
A solution of 4.30 g in tetrahydrofuran (10 ml) was added dropwise, and the mixture was stirred at room temperature overnight. After distilling off the solvent from the reaction mixture using a rotary evaporator, the residue was poured into about 20 ml of water, extracted with diethyl ether, and the obtained diethyl ether layer was washed successively with water, diluted hydrochloric acid, water, and sodium bicarbonate. , dried over anhydrous magnesium sulfate,
Diethyl ether was distilled off using a rotary evaporator to obtain a yellow liquid. This yellow liquid was heated under a reduced pressure of 1 mmHg.
The low-boiling components were distilled off by heating at 150°C for 30 minutes, and the residue was purified by silica gel column chromatography [using hexane/ethyl acetate = 98/2 (volume ratio) as the developing solution] to give a slightly yellow color. 2.48g liquid
I got it. The analysis results of this product are shown below. IR analysis: 1740, 1715, 1660, 830 cm ^{-1 1} H-NMR analysis: δ ^ppm _CCl4 1.21 (3H, t, -
CO ₂ CH ₂ CH ₃ ), 3.21 (1H, t, [formula]), 4.11 (2H, q, -CO ₂ CH ₂ CH ₃ ) FD-MASS analysis: m/e=1354 Based on the above analysis results, this The slightly yellow liquid was confirmed to be ethyl polyprenylketocarboxylate having _the general formula () where n=15 and ^R3 = _C2H5 . Next, this ethyl polyprenylketocarboxylate was added to a solution of 0.5 g of sodium hydroxide, 20 ml of ethanol, and 5 ml of water, and after stirring for 3 hours under reflux conditions, most of the ethanol was distilled off using a rotary evaporator. The residue was poured into about 20 ml of water, and concentrated hydrochloric acid was added little by little to make it acidic to a pH of about 2, followed by extraction with hexane. The hexane layer was thoroughly washed with saturated brine, dried over anhydrous magnesium sulfate, and the solvent was distilled off to obtain a yellow viscous liquid. This product was purified by silica gel column chromatography [hexane/ethyl acetate = 98/2 (volume ratio) was used as the developing solution] to obtain 1.98 g of slightly yellow viscous liquid.
I got it. The analysis results of this product are shown below. IR analysis: 1715, 1660, 830cm ^{-1 1} H-NMR analysis: δ ^ppm _CCl4 1.53 (s, 9H), 1.62 (s,
48H), 1.7-2.4 (m, 75H), 5.05 (br, 18H) FD-MASS analysis: m/e = 1282 The above analysis results show that this slightly yellow liquid is a polyester with n = 15 in the general formula (). It was confirmed to be prenylacetone. Next, 40 ml of anhydrous tetrahydrofuran and 220 mg of 50% sodium hydride were placed in a three-necked flask, and a solution of 1.0 g of ethyl diethylphosphonoacetate dissolved in 10 ml of anhydrous tetrahydrofuran was added dropwise while stirring at room temperature. After the dropwise addition was completed, stirring was continued for another hour at room temperature, and then a solution of 1.92g of polyprenylacetone synthesized earlier, where n = 15 in the general formula (), dissolved in 10ml of anhydrous tetrahydrofuran was added dropwise at room temperature, and the dropwise addition was completed. After 30 minutes at room temperature
The mixture was stirred for an additional 3 hours at 50-60°C. After cooling to room temperature and adding about 1 ml of water, the solvent was distilled off using a rotary evaporator, about 50 ml of water was added to the residue, and the mixture was extracted with hexane. The hexane layer was washed with saturated brine, dried over anhydrous magnesium sulfate, and the hexane was distilled off to obtain a yellow liquid. This liquid was purified by silica gel column chromatography [hexane/ethyl acetate = 98/2 (volume ratio) was used as a developing solution] to obtain 1.62 g of a colorless liquid. According to the analysis results below, this product has the general formula (V)
It was confirmed that it was polyprenylcarboxylic acid ethyl in which n=15 and R ¹ =C ₂ H ₅ . IR analysis: 1715, 1640, 1440, 1385, 1210, 1135, 830,
790cm ^{-1 1} H-NMR analysis (δ ^ppm _CCl4 ): 1.20 (t, 3H), 1.53 (s, 9H), 1.62 (s,
48H), 1.7-2.4 (m, 75H), 4.06 (q, 2H), 5.06
(br, 18H), 5.56 (br, 1H), FD-MASS analysis; m/e = 1352 Next, this polyprenylcarboxylic acid ethyl
Add 1.62 g of sodium hydroxide to a solution of 0.3 g of sodium hydroxide, 3 ml of water, and 20 ml of ethanol, stir under reflux conditions for 5 hours, then distill off most of the ethanol using a rotary evaporator, add 10 ml of water, and add dilute hydrochloric acid solution. The pH is about 5.
and then extracted with hexane. The hexane layer was washed with saturated brine, dried over anhydrous magnesium sulfate, and the solvent was distilled off to obtain a yellow liquid. This product was purified by silica gel column chromatography [using hexane/ethyl acetate = 90/10 (volume ratio) as a developing solution] to obtain 1.42 g of a colorless liquid. This product was confirmed to be a polyprenylcarboxylic acid having the general formula () where n=15 based on the following analysis results. IR analysis: 3600~2900 (weak), 2800~2400
(weak), 1690, 1660, 1630, 1440, 1375, 830 cm ^{-1 H} -NMR analysis: (δ ^ppm _CCl4 ): 1.53 (7.9H), 1.62 (s, 48H), 1.7-2.4 (m,
75H, 5.06 (br, 18H), 5.56 (br, 1H) ~ 11.5 (br,
1H). Next, 1.42 g of this polyprenylcarboxylic acid was selectively hydrogenated by the method shown below. μ,
0.7 mg of μ'-dichlorobis(1,5-cyclooctadiene)rhodium(I) and 7.3 mg of neomenthyl diphenylphosphine were placed in a pressure-resistant bottle, degassed while stirring with a magnetic stirrer, and then heated with argon. 5 ml of displaced and distilled absolute ethanol were added and the resulting yellow solution was stirred for 30 minutes under 3 atmospheres of hydrogen pressure. Apart from this, 1.42g of polyprenylcarboxylic acid and 17mg of sodium methoxide
A solution of was dissolved in 4 ml of absolute ethanol was stirred under an argon atmosphere. The catalyst solution and polyprenylcarboxylic acid solution thus prepared were transferred through the exhaust pipe to an autoclave that had been previously degassed and replaced with argon, and a hydrogenation reaction of 2.5 atm was applied at room temperature for 24 hours. I did it. The solution after the reaction was concentrated using a rotary evaporator, diluted hydrochloric acid was added to the residue, extracted with hexane, dried over magnesium sulfate, and the solvent was distilled off to form a yellow and colored liquid.
Obtained 1.40g. This was subjected to silica gel column chromatography [hexane/ethyl acetate = 90/10
(volume ratio) was used as a developing solution] to obtain 1.25 g of a colorless viscous liquid. This product has n=15 and R in general formula (I) according to the following analytical results.
It was confirmed that it was a dihydropolyprenylcarboxylic acid in which =H. IR analysis: 3600~2900 (weak), 2800~2400
(weak), 1705, 1660, 1440, 1375, 830 cm ^{-1 1} H-NMR analysis: (δ ^ppm _CCl4 ): 1.53 (s.9H), 1.62 (s, 48H), 1.7-2.5 (m,
76H, 5.06 (br, 18H), 10.0 (br, 1H) [δ5.56 (br, 1H) present in the raw material unsaturated polyprenylcarboxylic acid disappears] FD-MASS analysis; m/e = 1328 Similar By operation, n is 11 in the general formula ()
A dihydropolyprenylcarboxylic acid of the general formula (I) with a corresponding value of n and R=H was synthesized from a polyprenyl bromide with a value other than 15 between 19 and 19. Their yields were approximately the same as those obtained when dihydropolyprenylcarboxylic acid with n=15 was synthesized. Further, the characteristic absorption of their IR spectra and the characteristic signal of their ¹ H-NMR spectra substantially coincided with those of the dihydropolyprenylcarboxylic acid with n=15 at that position. Furthermore, the results of FD-MASS analysis were as follows. Value of n in raw material polyprenyl bromide () M/e value of dihydropolyprenylcarboxylic acid produced 11 1056 12 1124 13 1192 14 1260 16 1396 17 1464 18 1532 19 1600 Example 2 General compound synthesized by the method of Example 1 A solution of 1.15 g of polyprenylcarboxylic acid, where n is 15 in formula (), dissolved in 15 ml of tetrahydrofuran was added over 2 minutes to a blue solution prepared from 100 mg of lithium and 30 ml of liquid ammonia under a nitrogen stream. 30 more
After continued stirring at −33° C. for minutes, 3.0 g of ammonium chloride was added in portions to decompose the excess lithium. After leaving it as it is overnight to distill off the ammonia, add 3% hydrochloric acid to the residue, extract with hexane, dry the hexane layer with magnesium sulfate, and distill off the solvent using a rotary evaporator, leaving a yellow liquid. was gotten. Purified by silica gel column chromatography [using hexane/ethyl acetate = 90:10 (volume ratio) as the developing solution], 1.03 g of dihydropolyprenylcarboxylic acid having general formula (I) where n=15 and R=H. I got it. IR analysis of this,
The results of NMR analysis and FD-MASS analysis were consistent with those of dihydropolyprenylcarboxylic acid obtained in Example 1. By similar operation, n is 11 in the general formula ()
A dihydropolyprenylcarboxylic acid of the general formula (I) with a corresponding value of n and R=H was synthesized from a polyprenylcarboxylic acid with a value other than 15 between 19 and 19. Their yields were approximately the same as those obtained when dihydropolyprenylcarboxylic acid with n=15 was synthesized. Example 3 1.03 g of dihydropolyprenylcarboxylic acid of general formula (I), synthesized by the method of Example 1, where n is 15 and R=H, was dissolved in 20 ml of diethyl ether,
A diethyl ether solution of diazomethane was added while monitoring by thin layer chromatography until the spots of the starting carboxylic acid disappeared. After adding a small amount of acetic acid to decompose excess diazomethane, the mixture was concentrated using a rotary evaporator to obtain a yellow liquid. This product was purified by silica gel column chromatography (using hexane/ethyl acetate = 98:2 (volume ratio) as a developing solution) to obtain 1.01 g of a colorless liquid. The following analysis results confirmed that this product was methyl dihydropolyprenylcarboxylate in the general formula (I), where n was 15 and R=CH ₃ . IR analysis: 1735, 1660, 1440, 1375, 830cm ^{-1 1} H-NMR analysis: (δ ^ppm _CCl4 ): 1.53 (s, 9H), 1.62
(s, 48H), 1.7-2.5 (m, 76H), 3.68 (s, 3H),
5.06 (br, 18H) FD-MASS analysis: m/e = 1342 By similar operation, n is 11 in general formula (I)
Methyl dihydropolyprenylcarboxylate of the general formula (I) with a corresponding value of n from dihydropolyprenylcarboxylic acids with a value other than 15 between ~19 and R=H and with R=CH ₃ was able to synthesize. Example 4 In the general formula (I) synthesized in Example 3, n is
15. Dissolve 0.50 g of methyl dihydropolyprenylcarboxylate where R= _CH3 in 20 ml of absolute ethanol,
10 mg of 50% sodium hydride was added, and the mixture was heated under reflux for 14 hours. After cooling, ethanol was distilled off using a rotary evaporator, and water was added to the residue, which was then extracted with hexane and dried over magnesium sulfate. Hexane was distilled off using a rotary evaporator to obtain 0.43 g of a slightly yellow liquid. FD-MASS analysis of this product showed that m/e = 1356, so this liquid is an ethyl dihydropolyprenylcarboxylate represented by the general formula (I) where n is 15 and R=C ₂ H ₅ . It was confirmed that By similar operation, in general formula (I), n is 11
Ethyl dihydropolyprenylcarboxylate with values other than ₁₅ between ~19 and R= _C2H5 could also be synthesized. Example 5 A polyprenol mixture obtained in the same manner as in Reference Example 1, in which n is distributed from 11 to 19 in the general formula () and whose composition is substantially the same as that described in Reference Example 1, was added to the polyprenol mixture in Reference Example 2. A polyprenyl bromide mixture was obtained by reacting with phosphorus tribromide according to the method, and 4.30 g of it was prepared by the general formula () of Example 1.
polyprenyl bromide with n=15 in
The same operation as in Example 1 was carried out except that 4.30 g was used, and 1.18 g of a colorless viscous liquid was obtained as the final product. The IR and ¹ H-NMR analysis results of this product were substantially the same as those obtained for the dihydropolyprenylcarboxylic acid of Example 1 in terms of characteristic absorption and position of characteristic signals. Reference example 3 30ml of anhydrous tetrahydrofuran in a three-necked flask
and 380 mg of lithium aluminum hydride were added, and after cooling to 0°C under a nitrogen atmosphere, 4.42 g of dihydropolyprenylcarboxylic acid synthesized by the method of Example 1 and having n=15 and R=H in the general formula (I) was added to anhydrous solution. A solution dissolved in 15 ml of tetrahydrofuran was added dropwise with stirring. After the addition was completed, the mixture was stirred at 0° C. for 1 hour and at room temperature for an additional 5 hours, and then poured little by little into diluted hydrochloric acid and thoroughly stirred. Hexane was added to separate the layers, and the aqueous layer was further extracted twice with hexane. The organic layers were combined and washed with water, sodium bicarbonate, and saturated brine, dried over anhydrous magnesium sulfate, and the solvent was distilled off to form a colorless liquid.
Obtained 4.12g. This was subjected to silica gel column chromatography [hexane/ethyl acetate = 90:10
(volume ratio) was used as a developing solution] to obtain 3.82 g of a colorless liquid. This product was confirmed to be dolichol in which j=15 in the general formula (A) based on the following analysis results. IR analysis: 3320, 2920, 2850, 1440, 1376,
1060, 830cm ^{-1 1} H-NMR analysis: (δ ^ppm _CCl4 ): 0.91 (4, 3H), 1.60
(s, 9H, 1.68 (s, 48H), 1.10~1.80 (m, 5H),
2.03 (b, 70H), 3.66 (m, 2H), 5.10 (b, 18H) ^13C -NMR (ppm/intensity): 16.006/640,
17.679/353, 19.557/548, 23.430/6330,
25.308/567, 25.677/542, 26.436/5166,
26.699/548, 26.825/492, 29.316/528,
32.021/456, 32.245/5500, 37.548/582,
39.757/683, 40.029/541, 61.241/551,
124.214/445, 124.282/463, 124.448/505,
124.993/499, 125.071/5242, 131.210/213,
134.937/290, 1350.005/349, 135.229/3567,
135.365/430. FD-MASS analysis: m/e=1312 Example 4 20 ml of anhydrous diethyl ether and 200 mg of lithium aluminum hydride were placed in a three-necked flask, and after cooling to 0°C under a nitrogen atmosphere, the general formula synthesized by the method of Example 4 3.39 g of ethyl dihydropolyprenylcarboxylate in (I) where n is 15 and R=C ₂ H ₅
was dissolved in 10 ml of anhydrous diethyl ether and added dropwise with stirring. After the addition was completed, stirring was continued at room temperature overnight, and then 0.2 ml of water, 0.2 ml of a 15% aqueous sodium hydroxide solution, and 0.6 ml of water were carefully added dropwise in this order and stirred vigorously. The resulting white granular precipitate was separated, the organic layer was dried over anhydrous magnesium sulfate, and the solvent was distilled off to obtain 3.25 g of a colorless liquid. This product was purified by silica gel column chromatography [hexane/ethyl acetate = 90:10 (volume ratio) was used as the developing solution], and in the general formula (A), j = 15
3.03g of Dolichol was obtained. The results of IR analysis, NMR analysis and FD-MASS analysis of this product were consistent with those of Dolichol obtained in Reference Example 4.

Claims (1)

[Claims] 1. General formula (In the formula, [formula] represents a trans isoprene unit,
[Formula] represents a cis isoprene unit, n represents an integer from 11 to 19, and R represents a lower alkyl group or a hydrogen atom. ).