JPS646179B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing diterpene alcohol,
More specifically, from plants of the genus Croton, the formula (E, Z, E)-7-hydroxymethyl-3,11,15-trimethyl-2,6,10,14
This invention relates to a method for separating and collecting -hexadecatetraen-1-ol. The compound having the formula () is described in JP-A-52-70010,
It is a substance that has anti-peptic ulcer effects.

According to JP-A-52-70010, the method for producing the diterpene alcohol having the above formula (
(Croton sublyratus Kurz or Croton
Columnaris Airy shaw aka Croton joufra
Roxb.)], Plau-yai (Croton
oblongifolius Roxb.) and Plau
- Compounds contained in luat (Croton Hutchinsonianus Hosseus) are extracted with a solvent, and the extract is crystallized using a conventional plant neutral component separation method, a method that combines this with column chromatography, or a derivative. The desired product is isolated by a method of isolating the crystalline ester derivative and hydrolyzing the crystalline ester derivative.

The present inventors have made extensive studies with the aim of improving the yield, and have found that the extract contains the formula (In the formula, one of R ¹ and R ² represents an aliphatic acyl group, and the other represents a hydrogen atom, or both represent an aliphatic acyl group.) After conducting structural research on the ester and elucidating the fatty acids that make up the ester, it was discovered that the target compound () could be separated in good yield by hydrolyzing the ester, thereby completing the present invention. I've reached it.

Solvents used for extraction in the present invention include water or organic solvents commonly used for extracting plant components, such as alcohols such as methanol, ethanol and isopropanol, ethers such as ethyl ether and isopropyl ether,
Halogenated hydrocarbons such as dichloromethane, dichloroethane, and chloroform, acetate esters such as methyl acetate and ethyl acetate, lower alkyl ketones such as acetone and methyl ethyl ketone, and aromatic hydrocarbons such as benzene and toluene are particularly preferred. May be used without limitation. The fatty acids that form esters () in the extract include capric acid, palmitic acid, stearic acid, oleic acid,
Linoleic acid, linolenic acid, etc. are included as monoesters or diesters. In order to hydrolyze these esters, an aqueous alkali bicarbonate solution such as aqueous sodium bicarbonate solution, an aqueous sodium carbonate solution,
The treatment may be carried out by adding an aqueous alkali carbonate solution such as an aqueous potassium carbonate solution, an aqueous alkali hydroxide solution such as an aqueous sodium hydroxide solution or an aqueous potassium hydroxide solution, or an aqueous base solution of these bases may be added to an organic solvent during extraction. .

The reaction temperature in the above-mentioned hydrolysis and solvent extraction steps under basic conditions is not particularly limited, but it is usually preferable to carry out the reaction under heating and reflux.

A fraction containing the above-mentioned active ingredients can be obtained from this extract by a conventional method for collecting neutral components of plants. Furthermore, the compound having the above structural formula () can be isolated by a normal neutral component separation method, but it can also be isolated by using column chromatography in combination or by crystallizing it as a derivative. It is advantageous to do so.

That is, for example, in order to remove hydrocarbons from the extract, the extract or concentrate is washed with a hydrocarbon such as n-hexane, further dissolved in a water-immiscible solvent such as benzene or ether, and then washed with water. By drying the organic solvent layer with a drying agent such as anhydrous sodium sulfate and distilling off the solvent from the solution, it is possible to obtain a neutral substance fraction soluble in the organic solvent and having an anti-peptic ulcer effect.

To further isolate the desired active ingredient, fillers such as silica gel, alumina, and silicic acid are used, and one or two organic solvents such as benzene, ethyl ether, ethyl acetate, chloroform, acetone, and alcohol are used as developing solvents. Column chromatography is performed using the above mixed solvent or a mixed solvent of the above solvent and a petroleum solvent. The target compound is obtained by distilling off the solvent from the eluate, and if necessary, it can be further purified by conventional methods such as formation of derivatives or distillation under reduced pressure. That is, by treating neutral components obtained from plant extracts with crystalline derivative synthesis reagents commonly used for alcohol compounds, such as 3,5-dinitrobenzoyl chloride, phthalic anhydride, phenyl isocyanate, etc. After isolation as a crystalline derivative, the target compound can be isolated by hydrolyzing this.

Next, the method of the present invention will be explained in more detail with reference to Examples, but the method of the present invention is not limited thereto.

Example 1 2.8 kg of pulverized Thai medicine Prawn Noi was extracted three times with 10 methanol under heating and reflux. The extract was concentrated to a concentration of 5%, 10% aqueous sodium hydroxide solution was added thereto, and the mixture was hydrolyzed under heating under reflux for 0.5 hours.The solvent was distilled off, and the residue was extracted with ethyl ether. The ethyl ether solution was washed with water, dried over anhydrous sodium sulfate, and then the solvent was distilled off. 500 residue
It was adsorbed onto a column using 10 g of silica gel, first eluted with benzene containing 10% ethyl acetate, and then 30 g of silica gel was used.
% ethyl acetate in benzene. When the solvent in the portion containing the active ingredient in the benzene elution fraction containing 30% ethyl acetate was distilled off, 2.04 g of the desired diterpene alcohol (2) was obtained as a colorless viscous oil.

Example 2 1 kg of crushed Thai herbal medicine Pulau Noi was added to methanol 3 containing 150 ml of a 40% sodium hydroxide aqueous solution.
The mixture was extracted under heating under reflux. After distilling off the solvent of the extract, the residue was extracted with ethyl ether, and the ethyl ether solution was treated in the same manner as in Example 1 to obtain 0.77 g of the desired diterpene alcohol ().

Example 3 500g of crushed Croton sublyratus Kurz leaves
The mixture was extracted with 2.5 methanol containing 200 ml of 40% aqueous sodium hydroxide solution under heating under reflux for 1 hour. The extract was treated in the same manner as in Example 2 to obtain 3.0 g of the desired diterpene alcohol ().

Reference Example 1 5 kg of crushed Croton sublyratus Kurz leaves were extracted three times with 20 methylene chloride under heating and reflux. The extracts were combined and the solvent was distilled off, and the residue was adsorbed on a column using 1.5 kg of silica gel, and eluted with n-hexane. Collect a portion of the eluate,
The solvent was distilled off, the residue was hydrolyzed with methanol containing an aqueous sodium hydroxide solution, and the presence or absence of compound () was determined by thin layer chromatography (using silica gel, developing solvent benzene-ethyl acetate 1:
1) was investigated. In this way, fractions containing the ester form of compound () were collected and the solvent was distilled off.
The residue was adsorbed onto preparative silica gel thin layer chromatography and developed with benzene. In the same manner as above, the portion containing the ester form of compound () was examined and fractionated, and the following ester forms were isolated from each fraction.

Ester A R _f : 0.62 (silica gel thin layer chromatography,
(developing solvent benzene).

Infrared absorption spectrum νcm ^-1 (liquid film): 2925,
2850, 1740, 1460, 1380, 1240, 1170,
1120, 1030.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.4―
4.8 (multiplet), 4.46 (singlet), 4.41 (doublet), 2.5-1.8 (multiplet), 1.8-1.5 (multiplet), 1.25 (singlet), 1.85 (multiplet).

Ester B R _f :0.45 (same as above, developing solvent benzene).

Infrared absorption spectrum νcm ^-1 (liquid film): 2920,
2850, 1740, 1440, 1375, 1230, 1170,
1110, 1025.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.4―
4.7 (multiplet), 4.46 (singlet), 4.40 (doublet), 2.4-1.9 (multiplet), 1.9-1.5 (multiplet), 1.27 (singlet), 1.86 (multiplet).

Ester C R _f :0.70 (same as above, developing solvent benzene-ethyl acetate 20:1).

Infrared absorption spectrum νcm ^-1 (liquid film): 2925,
2850, 1740, 1450, 1380, 1235, 1170,
1125, 1080, 1030.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.4―
4.8 (multiplet), 4.47 (singlet), 4.41 (doublet), 2.5-1.85 (multiplet), 1.85-1.5 (multiplet), 1.26 (singlet), 1.88 (multiplet).

Ester D R _f :0.91 (same as above, developing solvent benzene-ethyl acetate 20:1).

Infrared absorption spectrum νcm ^-1 (liquid film): 2930,
2860, 1740, 1670, 1460, 1380, 1240,
1180, 1120, 970.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.4―
4.7 (multiplet), 4.46 (singlet), 4.41 (doublet), 2.5-1.8 (multiplet), 1.8-1.5 (multiplet), 1.27 (singlet), 1.88 (multiplet).

Ester E R _f :0.91 (same as above, developing solvent benzene-ethyl acetate 5:1).

Infrared absorption spectrum νcm ^-1 (liquid film): 2920,
2850, 1735, 1685, 1450, 1380, 1230,
1170, 1025.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.4―
4.8 (multiplet), 4.45 (singlet), 4.39 (doublet), 2.4-1.8 (multiplet), 1.8-1.5 (multiplet), 1.25 (singlet), 1.88 (multiplet).

Ester F R _f : 0.83 (same as above, developing solvent benzene-ethyl acetate 2:1).

Infrared absorption spectrum νcm ^-1 (liquid film): 3370,
2920, 2850, 1735, 1455, 1375, 1235,
1170, 1110, 1005.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.6―
4.7 (multiplet), 4.47 (singlet), 3.98 (doublet), 2.4-1.8 (multiplet), 1.8-1.5 (multiplet), 1.25 (singlet), 0.91 (multiplet).

Ester G R _f :0.80 (same as above, developing solvent benzene-ethyl acetate 1:1).

Infrared absorption spectrum νcm ^-1 (liquid film): 3360,
2920, 2850, 1735, 1715, 1675, 1635,
1435, 1375, 1235, 1170, 1110, 1005,
970.

Nuclear magnetic resonance spectrum δppm (CCl ₄ ): 5.6―
4.7 (multiplet), 4.45 (singlet), 3.96 (doublet), 2.4-1.9 (multiplet), 1.9-1.4 (multiplet), 1.27 (singlet), 0.93 (multiplet).

Among these esters, the results of nuclear magnetic resonance spectroscopy show that esters A, B, C, D and E are diesters of compound (), and esters F and G
was found to be a monoester containing only carbon 18.

Next, a portion of each of esters A, B, C, D, E, F and G was hydrolyzed in methanol containing an aqueous sodium hydroxide solution. After evaporating the solvent, dilute hydrochloric acid was added to the residue, and the mixture was extracted with ethyl ether. The ethyl ether layer was washed with water, dried over anhydrous sodium sulfate, and then the solvent was distilled off and dried. The obtained product was dissolved in ethyl ether, an ether solution of diazomethane was added, and the mixture was left at room temperature. This solution was subjected to gas chromatography (filling agent: 10% carbo wax).
20M, vaporization section, detection section temperature 200 degrees, column temperature 80 degrees
2 minutes after introduction of the sample, the temperature was increased to 250 degrees at a rate of 10 degrees per minute), and the fatty acids contained were determined by comparing the retention time with standard fatty acid methyl ester. As a result, esters A to G are
It was revealed that each of these is an ester consisting of the following fatty acids and compounds ().

Ester A: Capric acid and palmitic acid Ester B: Capric acid and oleic acid Ester C: palmitic acid and oleic acid Ester D: Oleic acid and palmitic acid Ester E: Linoleic acid and linolenic acid Ester F: stearic acid Ester G: Oleic acid

Claims (1)

[Claims] 1. An extract obtained by extracting a Croton genus plant with a solvent is hydrolyzed under basic conditions and then extracted with a solvent, or a Croton genus plant is directly subjected to basic conditions. A formula characterized by hydrolysis and simultaneous extraction with a solvent. A method for producing a diterpene alcohol having