JP2529095B2 - 13,14-Dihydro-15-keto-16-desbutyl-16-trifluoromethylphenoxy-prostaglandin E2 - Google Patents

Description

Detailed Description of the Invention

[0001]

This invention relates to a novel prostaglandin compound, 13,14-dihydro-15-
It relates to keto-16-desbutyl-16-trifluoromethylphenoxy-prostaglandin E ₂ .

[0002]

BACKGROUND OF THE INVENTION Prostaglandins (hereinafter prostaglandins are designated as PG) are a group of organic carboxylic acids that are contained in human and other mammalian tissues or organs and exhibit a wide range of physiological activities. Naturally occurring PGs have a prostanoic acid skeleton as a general structural property.

[0003]

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On the other hand, some synthetic analogs have modified backbones. Natural PGs have PGAs, PGBs, PGCs, PGDs, PGEs depending on the structural characteristics of the 5-membered ring.
, PGFs, PGGs, PGHs, PGIs and P
It is classified into GJs, and the chain part is also subscripted by the presence or absence of unsaturation and oxidation. . . 15-OH subscript 2. . . 5,6-Unsaturated-15-OH Subscript 3. . . 5,6- and 17,18-diunsaturated-15
Classified as -OH.

Native PGE ₁ , PGE ₂ and PGE ₃ are known to have vasodilatory, hypotensive, hypogastric secretion, intestinal motility, uterine contraction, diuretic, bronchodilator and antiulcer activity. Further, natural PGF ₁ α, PGF ₂ α and PGF ₃ α are known to have blood pressure elevation, vasoconstriction, intestinal motility, uterine contraction, luteal regression and tracheal constriction activity. Furthermore, PGF ₂ α is actually used as a parturition-promoting agent and is also known to have anti-pregnancy activity.
However, the use of PGF ₂ α has limitations due to its own undesirable side effects, such as intestinal contraction and intraocular pressure-boosting activity.

Also, some 15-keto (ie, having an oxo group at the 15-position instead of a hydroxyl group) prostaglandins and 13,14-dihydro-15-keto-prostaglandins are natural prostaglandins. Known as a substance that is naturally produced by the action of enzymes during metabolism of gins [Acta Physiologica Scadinavica
(Acta Physiologica Scandinavica), Volume 66, 50
Page 9, 1966]. Furthermore, it is also reported that 15-keto-prostaglandin F ₂ α has anti-pregnancy activity.

[0007]

DISCLOSURE OF THE INVENTION The object of the present invention is to provide a novel prostaglandin compound having uterine contractile activity.

[0008]

The present invention provides a free form, O-
Formula I in protected form, physiologically acceptable salt form, or physiologically acceptable and physiologically hydrolyzable ester form:

[0009]

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13,14-dihydro-15-
Provided is keto-16-desbutyl-16-trifluoromethylphenoxy-prostaglandin E ₂ and a uterine contractile agent containing the compound as an active ingredient.

As used herein, the term "uterine contraction" refers to
It refers to the contraction of part or all of the uterus and usually the myometrium. The term "abortion" means abortion of pregnancy, prevention of fertilization or implantation or miscarriage in the early to middle trimesters.

In the present specification, the nomenclature of prostanoic acid shown in formula (A) of PG compounds is used. The formula
(A) has a basic skeleton of C-20, but the number of carbon atoms is not limited thereto in the present invention. That is,
The carbon number of the basic skeleton is 1 for carboxylic acid and 5
2 to 7 toward the member ring to carbon on the α chain, 8 to 1
Up to 2 are attached to the carbon of the 5-membered ring and 13 to 20 are attached to the ω chain, but if the number of carbons decreases on the α chain, the number is deleted sequentially from the 2nd position and increases on the α chain. In this case, the compound is named as having a substituent in place of the carboxyl group (1-position) at the 2-position. Similarly, when the carbon number decreases on the ω chain, the carbon number is sequentially decreased from the 20th position, and when the carbon number increases on the ω chain, 2
The carbon atoms after the first are designated as substituents. Also,
Regarding the steric configuration, the steric configuration is the same as that of the basic skeleton unless otherwise specified.

Thus, the compound of formula I provided by this invention is designated 13,14-dihydro-15-keto-16-desbutyl-16-trifluoromethylphenoxy-prostaglandin E ₂ . On the other hand, when the compound of formula I is named based on IUPAC, (Z) -7-[(1
R, 2R, 3R) -2- {4- (3-trifluoromethylphenoxy) -3-oxobutyl} -3-hydroxy-5-
It becomes oxocyclopentyl] hept-5-enoic acid.

13,14-15-Keto-16-of the present invention
Desbutyl-16-triphenylmethylphenoxy-prostaglandin E ₂ is a physiologically acceptable salt form whether the carboxyl group at the α chain terminal is in the free form or in the O-protected form. May be.

The term "physiologically acceptable salt" includes conventional non-toxic salts, including salts with inorganic bases such as alkali metal salts (sodium salt, potassium salt, etc.), alkaline earth metal salts (calcium salt). Salt, magnesium salt, etc.), ammonium salt, a salt with an organic base, for example, an amine salt (for example, methylamine, dimethylamine salt, cyclohexylamine salt, benzylamine salt, piperidine salt, ethylenediamine salt,
Ethanolamine salt, diethanolamine salt, triethanolamine salt, tris (hydroxymethylamino) ethane salt, monomethyl-monoethanolamine salt, lysine salt, procaine salt, caffeine salt, etc., basic amino acid salt (for example, arginine salt, lysine) Salt etc.) Tetraalkylammonium salt and the like. These salts may be prepared, for example, from the corresponding acids and bases by conventional methods or by salt exchange.

Examples of "physiologically acceptable and physiologically hydrolysable esters" are methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, t-
Lower alkyl ester such as butyl ester, pentyl ester, 1-cyclopropylethyl ester, lower alkenyl ester such as vinyl ester, allyl ester,
Lower alkynyl ester such as ethynyl ester and propynyl ester, hydroxy (lower) alkyl ester such as hydroxyethyl ester, lower alkoxy such as methoxymethyl ester and 1-methoxyethyl ester
Aliphatic esters such as (lower) alkyl esters and optionally substituted aryl esters such as phenyl ester, tosyl ester, t-butylphenyl ester, salicyl ester, 3,4-dimethoxyphenyl ester, benzamide phenyl ester, benzyl Examples thereof include aryl (lower) alkyl esters such as ester, trityl ester and benzhydryl ester.

Preferably, instead of the free form in which the α chain end is --COOH and the carboxyl group, --COO
CH _3, -COOCH ₂ CH _3, a compound which is -COOCH (CH _{3) 2.}

In formula I above, the arrangement of the rings, α and / or ω chains may be the same or different from the arrangement of the natural prostaglandins. However, this invention
Also included are mixtures of compounds having a natural configuration and compounds having a non-natural configuration.

The compounds of the formula I according to the present invention are new and are disclosed in Japanese Patent Application Nos. 63-18326 and 63-10.
It can be produced by the method described in No. 8329. Alternatively, these compounds may be prepared by methods similar to those described herein or known.

To obtain the compounds of formula I according to the invention, 13,
A method for obtaining a 14-dihydro-15-keto-PGE ₂ derivative may be applied. As a specific production method for obtaining this PGE ₂ derivative, as shown in the synthesis chart, dimethyl compound (2-oxoheptyl) phosphonate anion is added to aldehyde derivative (2) obtained by Collins oxidation of commercially available corey lactone (1). To give an α, β-unsaturated ketone (3), which is reduced to give the corresponding saturated ketone (4),
The carbonyl group of the ketone is reacted with a diol to protect it as the corresponding ketal (5), followed by de-p-phenylbenzoylation to give the corresponding alcohol (6), the newly generated hydroxyl group being protected with dihydropyran, It is tetrahydropyranyl ether (7). As a result, a precursor of prostaglandin Es in which the ω chain is a 13,14-dihydro-15-ketoalkyl group is obtained. Furthermore, tetrahydropyranyl ether (7) is reduced to give lactol.
(8) was obtained, which was reacted with an ylide obtained from (4-carboxybutyl) triphenylphosphonium bromide to obtain a carboxylic acid (16), which was then esterified (17) and then Jones oxidized (18), The 15-keto-prostaglandin E ₂ can then be obtained by removing the protecting group. The method for synthesizing the compound of the present invention is not limited to this, and a suitable method may be adopted as a method for protecting each functional group, a redox method, and the like.

[0021]

EFFECTS OF THE INVENTION Since the compound of the present invention exhibits a strong uterine contraction effect and an effect of suppressing the implantation of eggs, a uterine contractor or a pharmaceutical composition, particularly therapeutic abortion, artificial abortion and / or contraception, It can be used for the treatment of fetal discharge and bleeding in incomplete abortion, bleeding after abortion, postpartum hemorrhage, labor pain promotion, bleeding after curettage, delivery induction, uterine reversion after delivery, irregular bleeding during menstruation and the like. The compounds of the present invention are excellent in almost completely avoiding side effects such as intestinal contraction when used in the above indications.

The compound of the present invention can be used as a drug for animals and humans, and is usually systemically or locally administered orally, intravenously (including instillation), subcutaneously, suppository, extraovular administration, etc. Used in the method of. The dose varies depending on the animal, human, age, body weight, symptom to be treated, desired therapeutic effect, administration method, treatment period, etc., but when administered in 2 to 4 divided doses or continuous form per day. 001
A sufficient dose is usually obtained at a dose of ~ 500 mg / kg.

Solid compositions for oral administration according to the present invention include tablets, troches, sublingual tablets, capsules, pills, powders, granules and the like. In such solid compositions the active substance is at least one inert diluent such as lactose, mannitol, glucose, hydroxypropyl cellulose, microcrystalline cellulose, starch,
It is mixed with polyvinylpyrrolidone and magnesium aluminometasilicate. According to a conventional method, the composition may be an additive other than an inert diluent, for example, a lubricant such as magnesium stearate or a disintegrating agent such as calcium fibrinate gluconate, α, β or γ-cyclodextrin, dimethyl- Etherified cyclodextrins such as α-, dimethyl-β-, trimethyl-β- or hydroxypropyl-β-cyclodextrin, branched cyclodextrins such as glycosyl-, maltosyl-cyclodextrins, formylated cyclodextrins, sulfur-containing cyclodextrins , May also contain stabilizers such as misoprotol, phospholipids. When the above cyclodextrins are used, an inclusion compound may be formed with the cyclodextrins to increase the stability in some cases. In addition, stability may be increased by forming liposomes using phospholipids. If necessary, the tablets or pills may be coated with a film of a gastric or enteric substance such as sucrose, gelatin, hydroxypropylcellulose, hydroxypropylmethylcellulose phthalate, or may be coated with two or more layers. Further, it may be a capsule of an absorbable substance such as gelatin. When immediate action is required, a sublingual tablet may be used. Glycerin, lactose and the like may be used as a base.

Examples of liquid compositions for oral administration include emulsions, solutions, suspensions, syrups and elixirs. It may contain a commonly used inert diluent, for example, purified water, ethanol and the like. The composition may contain, in addition to the inert diluent, adjuvants such as wetting agents and suspending agents, sweetening agents, flavoring agents, fragrances, and preservatives. Other compositions for oral administration include sprays which contain the active substance and are formulated in a manner known per se.

The injections for parenteral administration according to the present invention include sterile aqueous or non-aqueous liquids, suspensions and emulsions. Aqueous solutions and suspension media include, for example, distilled water for injection, physiological saline and Ringer's solution. Examples of non-aqueous liquids and suspension media include propylene glycol, polyethylene glycol, vegetable oils such as olive oil, alcohols such as ethanol,
There are polysorbates and the like. Such compositions may also contain adjuvants such as preserving, wetting, emulsifying, and dispersing agents. These are sterilized by, for example, filtration through a bacteria retaining filter, blending of a bactericide, gas sterilization or radiation sterilization. They can also be used to produce sterile solid compositions which are dissolved in sterile water or sterile injectable solvents before use.

Another form of uterine contractile agent of this invention is a suppository or vaginal suppository. These suppositories can be prepared by mixing an active ingredient with a base softening at body temperature such as cacao butter, and the absorbency may be improved by using a nonionic surfactant having an appropriate softening temperature.

[0027]

EXAMPLES By referring to the examples shown below,
A more complete understanding of the invention is possible. The examples are for purposes of illustration only and are not intended to limit the scope of the invention.

Production of Compound Production Example 1 Production of dimethyl (3-m-trifluoromethylphenoxy-2-oxopropyl) phosphonate. 8.1 g of trifluoromethylcresol were dissolved in 30 ml of water containing 2 g of sodium hydroxide. On the other hand, 9.45 g of chloroacetic acid was dissolved in 50 ml of water containing 4 g of sodium hydroxide and added at room temperature to an aqueous solution of trifluoromethylcresol. Heat to 110 ° C. for 28 hours with stirring. After cooling, the mixture was acidified with diluted hydrochloric acid, the white precipitate formed was filtered off, washed with water, dissolved in ethyl acetate, and dried over magnesium sulfate. The solution was concentrated under reduced pressure to obtain m-trifluoromethylphenoxyacetic acid. The above m-trifluoromethylphenoxyacetic acid was made into the methyl ester using diazomethane in ether. The crude product obtained as a concentrate was purified by column chromatography. Yield: 7.3g

A solution of 7.8 g of dimethyl methylphosphonate in 200 ml of dry tetrahydrofuran (THF) was cooled to -78 ° C, and n-butyllithium (1.6-M) was added dropwise thereto. After stirring for 40 minutes, a dry THF solution of 7.3 g of methyl m-trifluoromethylphenoxyacetate was added dropwise. Four
After the time was maintained at -78 ° C, 4 g of acetic acid was added. After being brought to room temperature, it was concentrated under reduced pressure, and the obtained residue was extracted with ethyl acetate and dried. The ethyl acetate solution was concentrated, and the resulting crude product was purified by chromatography to obtain dimethyl (3-m-trifluromethylphenoxy-2-oxopropyl) phosphonate. Yield: 8.3g

Production Example 2 IS-2-oxa-3-oxo-6R- (3-oxo-
Preparation of 4-m-trifluoromethylphenoxy-1-trans-butenyl) -7R-p-phenylbenzoyloxy-cis-bicyclo [3.3.0] octane (23).

[0031]

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Sodium hydride suspended in 50 ml of THF
To 0.282 g of (60%), a solution of 2.3 g of the above-mentioned dimethyl (3-m-trifluoromethylphenoxy-2-oxopropylphosphate) in 20 ml of THF was added dropwise, and the mixture was stirred for 30 minutes. ) Corey Lactone (21) (2.
TH of aldehyde (22) obtained by Collins oxidation of 5 g)
30 ml of F solution was added. By a conventional treatment, α.ρ-unsaturated ketone (23) was obtained.

Production Example 3 IS-2-oxa-3-oxo-6R- (3-oxo-
4-m-trifluoromethylphenoxybutyl) -7R
-P-phenylbenzoyloxy-cis-bicyclo [
3.3.0] Production of octane (24).

[0034]

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5% of the unsaturated ketone (23) obtained in Preparation Example 2 was used.
Catalytic reduction was carried out with 50% ethyl acetate in 50 ml of ethyl acetate. Yield: 1.68g

Production Example 4 IS-2-oxa-3-oxo-6R- (3R, S-hydroxy-4-m-trifluoromethylphenoxybutyl) -7R-p-phenylbenzoyloxy-cis-
Production of bicyclo [3.3.0] octane (25).

[0037]

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1.68 g of Titon (24) was added to 25 m of methanol.
reduction with sodium borohydride (0.027 g) in
After silica gel chromatography (ethyl acetate: hequinsan = 3: 2 → 2: 1), alcohol (25) was obtained. Yield: 1.
58g

Production Example 5 IS-2-oxa-3-oxo-6R- [3R, S-t-
Butyldimethylsilyloxy-4-m-trifluoromethylphenoxybutyl) -7R-p-phenylbenzoyloxy-cis-bicyclo [3.3.0] octane (2
6) Production.

[0040]

[Chemical 6]

1.58 g of alcohol (25) was made into a silyl coatel (26) using 1.20 g of t-butyldimethylsilyl chloride and 1.08 g of imidazole in 3 ml of dimethylformamide (DMF). It was purified by silica gel catem chromatography (ethyl acetate: hekinsan = 1: 2). Yield: 1.28g

Production Example 6 IS-2-oxa-3-oxo-6R- (3R, S-t-
Butyldimethylsilyloxy-4-m-trifluoromethylphenoxybutyl) -7R-hydroxy-cis-
Production of bicyclo [3.3.0] octane (27).

[0043]

[Chemical 7]

1.98 g of silyl ether (26) was dissolved in 40 ml of dry methanol, 0.383 g of potassium carbonate was added, and the mixture was stirred at room temperature for 5 hours. Ice-cooled, acetic acid 0.333 g
After dripping, a crude product was obtained by a conventional method. Silica gel chromatography (Ethyl acetate: Hekinsan =
Purification by 1: 2) gave alcohol (27). Yield: 1.2
1 g

Production Example 7 IS-2-oxa-3-oxo-6R- (3R, S-t-
Preparation of butyldimethylsilyloxy-4-m-trifluoromethylphenoxybutyl) -7R- (2-tetrahydropyranyl) oxy-cis-bicyclo [3.3.0] octane (28).

[0046]

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1.21 g of alcohol (27) was added to dihydropyran (4 ml) and a catalytic amount of p in 80 ml of dichloromethane.
-Tetrahydropyranyl ether (28) using toluene sulfonic acid. Yield: 1.40g

Production Example 8 IS-2-oxa-3R, S-hydroxy-6R- (3
Production of R, S-t-butyldimethylsilyloxy-4-m-trifluoromethylphenoxybutyl) -7R- (2-tetrahydropyranyl) oxy-bicyclo [3.3.0] octane (29). Tetrahydropyranyl ether
(28) 1.40 g of DIBAC- in 25 ml of dry toluene
Lactol (29) was made using H (1.5-M, 2.9 ml). Yield: 1.40g

[0049]

[Chemical 9]

Production Example 9 13,14-Dihydro-15R, S-t-butyldimethylsilyloxy-16-desbutyl-16-m-trifluoromethylphenoxy-11R- (2-tetrahydropyranyl) oxy-PGF ₂ α Production of (30) and its methyl ester (31).

[0051]

[Chemical 10]

DMS of (4-carboxybutyl) triphenylphosphonium bromide (4.33 g) in methylsulfinicarbanion obtained from sodium hydride and DMSO.
DMS of lactol (29) in ylide obtained by adding O solution
O solution was added. After 3 hours, the usual treatment was performed to obtain 13,1.
Give trifluoromethylphenoxy -11R- (2-tetrahydropyranyl) oxy-PGF ₂ alpha (30) - 4-dihydro--15R, S-t- butyldimethylsilyloxy-16-Desubuchiru -16- m. The crude product (30) was treated with diazomethane to give 13,14-dihydro-15R,
S-t-butyldimethylsilyloxy-16-desbutyl-16-m-trifluoromethylphenoxy-11
R- (2-Tetrahydropyranyl) oxy-PGF ₂ α methyl ester (31) was obtained.

Production Example 10 13,14-Dihydro-15R, S-hydroxy-16-
Desubuchiru -16- m-trifluoromethylphenoxy-butyl -11R- (2-tetrahydropyranyl) oxy-PGF ₂ alpha methyl ester (32) prepared.

[0054]

[Chemical 11]

0.67 g of methyl ester (31) was added to THF.
Dissolved in tetrabutylammonium fluoride (1M,
1 ml) was added, and the mixture was reacted at room temperature for 12 hours. The crude product obtained by the conventional treatment was purified by silica gel chromatography to obtain a diol (32). Yield: 0.227g

Production Example 11 13,14-Dihydro-15-keto-16-desbutyl-16-m-trifluoromethylphenoxybutyl-
11R- (2-tetrahydropyranyl) oxy-PGE ₂
Preparation of methyl ester (33).

[0057]

[Chemical 12]

0.227 g of diol (32) was added to Ascent 3
Jones oxidised in 0 ml at -18 to -20 ° C. The crude product obtained after conventional treatment was purified by silica gel chromatography to give the diketone (33). Yield: 0.135
g

Production Example 12 13,14-Dihydro-15-keto-16-desbutyl-16-m-trifluoromethylphenoxy-PGE ₂
Production of methyl ester (34).

[0060]

[Chemical 13]

0.135 g of diketone (33) was added to acetic acid: TH
F: dissolved in water (3: 1: 1, 15 ml) and kept at 40-45 ° C. for 4 hours. The crude product obtained after the conventional treatment was purified by silica gel chromatography to obtain 13,14-dihydro-15-keto-16-desbutyl-16-m-trifluoromethylphenoxy PGE ₂ (34). Yield: 0.086g

Production Example 13 13,14-Dihydro-15-R, S-hydroxy-16
-Desbutyl-16-m-trifluoromethylphenoxy-11R- (2-tetrapyranyl) oxy-PGE ₂ α
Production of (35).

[0063]

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A solution of 0.327 g of carboxylic acid (34) in THF was added with tetrabutylammonium fluoride (1-M, 0.03).
55 ml) was added and the mixture was stirred for 2 days. The crude product obtained by the conventional treatment was purified by silica gel chromatography to obtain a diol (35). Yield: 0.152g

Production Example 14 13,14-Dihydro-15-keto-16-desbutyl-16-m-trifluoromethylphenoxy-11R
-(2-Tetrahydropyranyl) oxy-PGE ₂ (36)
Manufacturing of.

[0066]

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0.152 g of the above diol (35) was Collins-oxidized. The obtained crude product was purified by silica gel chromatography to obtain a diketone (36). Yield: 0.10
3 g

Production Example 15 13,14-Dihydro-15-keto-16-desbutyl-16-m-trifluoromethylphenoxy-PGE ₂
Production of (37).

[0069]

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0.103 g of the above diketone (36) was added to acetic acid
Dissolve in THF-water (3: 1: 1, 20 ml), 35-45 ° C
I kept it for 3.5 hours. The crude product obtained by a conventional method was purified by silica gel chromatography to give 13,14-
Dihydro-15-keto-16-desbutyl-16-trifluoromethylphenoxy-PGE ₂ was obtained. Yield: 0.
0373g

Formulation Example Formulation Example 1 16-Desbutyl-13,14- in methanol (10 ml)
Dihydro-15-keto-16- (m-trifluoromethyl) phenoxy-PGE ₂ methyl ester (50 mg) was dissolved and the resulting solution was mixed with mannitol (18.5 g). Sift the mixture (pore size: 300μm), 30 ℃
And dried for 90 minutes and then sieved again. The resulting powder was mixed with particulate silica gel (Aerosil, 200 g) and the mixture was filled into # 3 hard gelatin capsules (100). Capsules are 0.5 mg per capsule 13,1
4-dihydro-15-keto-16-desbutyl-16-
An enteric-coated capsule containing m-trifluoromethylphenoxy-PGE ₂ methyl ester.

[0072] The above ingredients were mixed, stirred, sterilized, filtered and lyophilized to give a powder for injection.

[0073] The above ingredients were mixed and lyophilized to give an injectable solution.

[0074] The above ingredients were mixed to obtain a powder for oral administration.

[0075] The above ingredients were mixed and filled into gelatin soft capsules.
In the above formulation examples, the active ingredient may be replaced with any other compound within the range used in this invention.

Biological Test Test Example 1 (Uterine contraction) Rats in estrus (female, about 150 g) were used as test animals. After exsanguination of the rat, the uterus is removed and the length is 1.5.
A piece of about 2.5 cm was cut off and suspended in a Magnus tube containing Tyrode's solution. After resting for about 5 minutes until the removed uterus is stable, 1 m of Oxytocin
Shrink with U several times. After stable uterine motility is obtained, 13,14-dihydro-15-keto-16-desbutyl-16-m-trifluoromethylphenoxy PGE ₂ is administered. The contraction of the reagent solution was expressed as a ratio with the contraction of 1 mU of oxytocin as 100. The results are shown below.

Concentration (M) Shrinkage (%) 1 × 10 ⁻⁶ 32 3 × 10 ⁻⁶ 73

Test Example 2 (Anti-pregnancy) Golden hamsters (female, 9 weeks old) were counted from the day on which sperm was observed in the viscous substance of the vagina (the first day), the 4th, 5th, and 6th of pregnancy. On day 6, test compounds were administered subcutaneously. On the 8th day, kill the animal and continue pregnancy or abort
Determined by the presence or absence of intrauterine implantation signs.

13,14-Dihydro-15-keto-16
When-desbutyl-16-m-trifluoromethylphenoxy-PGE ₂ was administered at a dose of 500 μg / hamster, no signs of implantation were observed in 2 out of 6 animals and fetal death was observed. It was observed in 4 out of 6 animals. This indicates that it has an anti-pregnancy effect.

[Brief description of drawings]

FIG. 1 shows a synthesis chart of 13,14-dihydro-15-keto-prostaglandin E ₂ .

FIG. 2 is a continuation of the chart of FIG.

Claims (3)

(57) [Claims] 1. A free form, an O-protected form, a physiologically acceptable salt form, or a physiologically acceptable and physiologically hydrolyzable ester form of 13,14-.
Dihydro-15-keto-16-Desubuchiru-16-trifluoromethylphenoxy - prostaglandin E _2. 2. A free form, an O-protected form, a physiologically acceptable salt form, or a physiologically acceptable and physiologically hydrolyzable ester form of 13,14-.
A uterine contractor containing dihydro-15-keto-16-desbutyl-16-trifluoromethylphenoxy-prostaglandin E ₂ as an active ingredient. 3. The agent according to claim 2 for abortion.