DD202565A5 - PROCESS FOR PREPARING A MUSHROOM PREVENTIVE COMPOUND - Google Patents

Abstract

A process for the preparation of an antifungal agent of formula I and the pharmaceutically acceptable salts thereof of pharmaceutical compositions containing them is disclosed. Formula I

Description

ι- 9 /, η /. 7 η

Process for the preparation of a fungal infestation

connection

Field of application of the invention

The invention relates to a novel bis-triazole derivative which has antifungal activity and is useful in the treatment of fungal infections in animals including humans.

Characteristic of the known technical solutions

British Patent Application No. 2 078 719 A (ICI), published on 13.1.1982, and European Application No. 0044605 (ICI), published 27.1.1982, disclose compounds of the general formula

OH γ1-ν-CH "- C-CH ² -NY ₀

yj ν-

wherein R is an optionally substituted alkyl, cycloalkyl (e.g., cyclopentyl or cyclohexyl), aryl (e.g., phenyl)

1 is 2 or aralkyl (e.g., benzyl) group and Y and Y are CH- or = N-, and their salts or metal complexes, ethers or esters.

These compounds are said to be useful as fungicides and plant growth regulators. They should also be active against fungal diseases in humans.

In particular, these applications in Example 2 and Claim 7 disclose 1,3-bis- (1,2,4-triazol-1-yl) -2- (2,4-dichlorophenyl) -propan-2-ol. This compound has the formula

OH

N, N-CH ₂ - C-CH ₂ -NN

Cl

Explanation of the essence of the invention

According to the invention, the compound of formula

.. OH ^ _s ^

NN-CH ₂ -C-CH ₂ -N> i (I)

F and their pharmaceutically acceptable salts are available.

posed. The 2,4-difluorophenyl compound prepared according to the invention is not specifically disclosed in the ICI applications, nor is "2,4-difluorophenyl" particularly suitable as a preferred

zugtes example for "R" named.

The known 2,4-dichlorophenyl compound is teratogenic, while quite unexpectedly the 2,4-difluorophenyl analog according to the invention is not teratogenic.

In addition, the corresponding 2-, 3- and 4-chlorophenyl and 4-bromophenyl analogs are teratogenic.

This was determined by the following teratology studies: teratology studies

After insemination, female rats (Cr1: COBS-CD (SD) BR, Charles River Breeding Colony, France) were randomized into groups of five animals. The test compounds were administered daily as a suspension in 0.1% aqueous methylcellulose by gastric intubation for ten consecutive days from the 6th. administered until the 15th day after insemination.

The animals were sacrificed on the 20th day after insemination and the number of killed fetuses was recorded along with the number, sex and weight of living fetuses. All fetuses were examined for external, oral and visceral anomalies.

The compounds tested were as follows:

üT

N-CH ₂ -C-CH ₂

OH

240470

wherein R = 2,4-dichlorophenyl, 2-, 3- and 4-chlorophenyl, 4-bromophenyl or 2,4-difluorophenyl.

All fetuses of animals treated with the compound in which R = 2,4-dichlorophenyl, at 20 mg / kg body weight, showed external malformations, especially cleft palates. Examination of visceral and skeletal characteristics showed that this compound was teratogenic at doses as low as 1 mg / kg, e.g. Presence of microphthalmia, increased incidence of dilatation of the ureters and renal pelvis, delayed bone formation of some bones and increased incidence of a 14th pair of ribs.

Also, the compound with R = 4-chlorophenyl was extremely embryotoxic at 20 mg / kg, while the compound with R = 2-chlorophenyl in this dose caused external abnormalities (cleft palate). These compounds are specifically listed as "Compounds 1 and 9", respectively, in Table 1 of the ICI applications. In addition, the compounds having R = 3-chlorophenyl and R = 4-bromophenyl which are claimed but not specifically disclosed in the ICI applications also evoked the same external abnormalities at 20 mg / kg. The latter compound was also embryotoxic at this dose.

The compound specifically prepared according to the invention, i.e., the compound in which R = 2,4-difluorophenyl most surprisingly did not elicit any external malformations when administered to pregnant rats under identical conditions. Internal examination of fetuses from these animals revealed no significant bowel or intestinal abnormalities.

The fetotoxicity (teratogenicity and / or embryotoxicity) of the compounds in which R has a meaning other than 2,4-difluorophenyl is a major drawback when they are to be used for human mycoses.

240 4 70

The invention also provides a pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof together with a pharmaceutically acceptable diluent or carrier. The composition is preferably for human use and in tablet, capsule, injectable or ointment form.

In addition, the invention provides a method of treating a fungal infection in an animal, including humans, comprising administering to an human an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof.

The invention further provides a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of fungal infections in humans.

The compound of formula (I) can be obtained by a number of different methods. In a process according to the invention, it is prepared by reacting the oxirane of the formula

(ID

with 1,2,4-triazole, preferably in the presence of a base.

The preferred bases are potassium carbonate and sodium hydride.

In a typical procedure, 1,2,4-triazole, the oxirane (II) and anhydrous potassium carbonate together in a suitable solvent, e.g. dry dimethylformamide,

preferably reacted with heating to 50 to 120 ° C to accelerate the reaction, which is generally completed in 8 hours or less. The product can be isolated and purified by conventional methods.

The triazole starting material may also be used in the form of the acid addition salt (e.g., mesylate), in which case excess base should be used.

The oxirane (II) can be obtained by conventional methods, typically from the corresponding ketone (III):

OT-CH ₂ -C

(III)

by reacting with dimethyloxosulfonylmethylid, prepared from trimethylsulfoxonium iodide and cetrimide / sodium hydroxide.

This reaction is typically carried out as follows: The ketone (III), trimethylsulfoxonium iodide and cetrimide are vigorously stirred in a mixture of toluene and aqueous sodium hydroxide solution at up to about 100 ^° C. for several hours. The oxirane product can then be isolated by conventional procedures.

The ketone (III) can be prepared by conventional methods, e.g. as follows:

£ 0470

+ ClCH ₂ COCl

AlCl ₃

Il

1,2,4-triazole, base

C-CH ₀ - N

In addition, the invention provides a process for the preparation of the compound of formula (I) as follows:

OH

Q-CH ₀ -C-CH ₀ -Q

^{Z1 Δ} base (cf., for example, J. Org. Chem., 27

'F

(IV)

2241-3, 1962)

OH

-CH _n -C-CH.

N N

(D

Hal-CH ₂ -C

(Q is a readily leaving group, preferably Cl, Br or J).

Presumably, this reaction forms the oxirane intermediate of formula (V) which, if desired, is isolated

can be.

Eei a typical reaction, the compound (IV) and 1,2,4-triazole are heated together, for example, up to 120 ⁰ C, in a suitable solvent, for example dry N, N-Dimethy1formamid or tetrahydrofuran, for up to about 24 hours , preferably in the presence of a base, for example potassium carbonate. In general, an excess of the triazole and base are used. The product (I) can then be isolated and purified according to conventional procedures.

In both processes described above, the product (I) will generally be contaminated with the isomer in which one of the triazole rings on adjacent CH _{2 is} pendant from the 4 position, but this undesired isomer can be removed chromatographically, eg, on silica gel or by recrystallization.

The starting material of formula (IV) can be obtained by conventional procedures, e.g. as follows:

F ^ Q) -MgJ

+ Hal CH ₂ CCH ₂ -HaI

CH • Hal-CH ₂ -C-CH ₂ -HaI

(IV)

The preferred pharmaceutically acceptable salts are the acid addition salts. Pharmaceutically acceptable acid addition salts of the compound of formula (I) are those formed from strong acids which form non-toxic acid addition salts and contain pharmaceutically acceptable anions such as the hydrochloride, hydrobromide and sulphate.

The salts can be obtained by conventional procedures, e.g. by mixing solutions containing equimolar amounts of the free base and the desired acid, and the desired salt, if insoluble, is recovered by filtration or by evaporation of the solvent.

The compound of formula (I) and its pharmaceutically acceptable salts are highly active antifungal agents useful for combating fungal infections in animals, including humans. For example, they are useful in the treatment of local fungal infections in humans, i.a. by organisms of the genus Candida, Trichophyton, Microsporum or Epidermophyton, or mucosal infections caused by Candida albicans (e.g., thrush and candidiasis of the vagina). They may also be used in the treatment of systemic fungal infections caused, for example, by Candida albicans, Cryptococcus neoformans, Aspergillus fumigatus, Coccidioides, Paracoccidioides, Histoplasma or Blastomyces.

The in vitro detection of the antifungal activity of the compound (I) can be done by determining the minimum inhibitory concentration (MIC) which is the concentration of the test compound in a suitable medium in which growth of the specific microorganism no longer occurs. In practice, a series of agar plates, each with the test compound in a certain concentration, are incubated with a standard culture of e.g. Inoculated Candida albicans and each

ίο -

lh U 4

Plate then incubated for 48 h at 37 ° C. The plates are then checked for the presence or absence or growth of the fungus and the corresponding value of the MIC noted. Other microorganisms used in such assays may include Cryptococcus neoformans, Aspergillus fumigatus, Trichophyton spp, Microsporum spp, Epidermophyton floccosum, Coccidioides immitis and Torulopsis glabrata.

In vivo evaluation of the compound can be done in a variety of dose levels by intraperitoneal or intravenous injection or by oral administration to mice inoculated with a strain of Candida albicans. Untreated mice die within 48 hours and the dose level at which the compound provides 50% protection against the lethal effect of the infection is noted. The connection

(I) gives at least 50% protection at below 0.5 mg / kg (p.o. or i.v.).

For human use, the antifungal compound of formula (I) (or its salt) may be administered alone, but will generally be administered in admixture with a pharmaceutical carrier selected with regard to the intended route of administration and standard pharmaceutical practice. For example, it may be administered orally in the form of a tablet containing excipients, such as starch or lactose, or in a capsule or ovule, either alone or in admixture with excipients, or in the form of an elixir or suspension containing flavoring or coloring agent. It can be parenteral, e.g. injected intravenously, intramuscularly or subcutaneously. For parenteral administration, it is best used in the form of a sterile aqueous solution which may contain other substances, e.g. enough salts or glucose to make the solution isotonic.

For oral and parenteral administration to human patients, the daily dose of the antifungal compound of formula (I) is expected to be 0.1 to 5 mg / kg (in divided doses) when administered orally or parenterally. Thus, tablets or capsules of the compounds will contain from 5 mg to 0.5 g of active compound for administration individually or two or more simultaneously as appropriate. The physician will in any case determine the actual dosage that is most appropriate for a single patient and will vary with the age, weight and response of the particular patient. The above doses are exemplary of the average case. Of course, there may be isolated cases where higher or lower dose ranges are beneficial, and they are also within the scope of the invention.

On the other hand, the antifungal compound of formula (I) may be applied in the form of a suppository or pessary, or topically in the form of a lotion, solution, ointment or dusting powder. For example, it may be incorporated into an ointment consisting of an aqueous emulsion of polyethylene glycols or liquid paraffin, or it may be incorporated at a concentration between 1 and 10% in an ointment composed of a bleached wax or a bleached soft paraffin base together with necessary Stabilizers and preservatives.

The following examples illustrate the invention: Example 1

Preparation of 2- (2,4-difluorophenyl) -1,3-bis (1H-1,2,4-triazol-1-yl) propan-2-ol

(ClCH ₂ )

, C = O + F- / Λ-Li

' ^K 2 ^CO 3

OH

Ii-N-CH ₂ -C-CH ₂ -N -N

(i) A solution of T-bromo-2,4-difluorobenzene (0.96 g, 5 mmol) in diethyl ether, (10 mL) was stirred at -78 ° C and a solution of n-butyllithium (1.55 g) was added. molar, 3.23 ml, 5 mmol) in hexane over 3 min. After completion of the addition, the mixture was stirred for a further 10 minutes and then a solution of 1,3-dichloroacetone (0.63 g, 5 mmol) in diethyl ether (10 ml) was added dropwise over 3 minutes. After a further 30 min stirring at -78 ⁰ C a solution of acetic acid (0.33 g) in diethyl ether (5 ml) at 0 ⁰ C, then water (10 ml) was added. The organic layer was separated and the aqueous layer washed once with diethyl ether. The combined ether extracts were dried (over MgSO 4) and concentrated to a pale yellow oil which was dissolved in dimethylformamide (20 ml). This DMF solution contained the intermediate (IVB).

(ii) 1,2,4-triazole (1.72 g, 25 mmol) and anhydrous potassium carbonate (2.07 g, 15 mmol) were added to the prepared under (i) solution and the mixture 18 h at 70 ⁰ C. heated.

The reaction mixture was cooled and poured into water (100 ml). The aqueous mixture was extracted twice with ethyl acetate. The combined organic extracts were dried (over MgSO ₄ ) and concentrated to a resin. The resin was chromatographed on silica gel (0.053-0.037 mm and 270-400 mesh, respectively) eluting with 3% methanol in methylene chloride to give the title compound, a white solid, 0.40 g (26%, based on dichloroacetone), m.p. (after recrystallization from ethyl acetate / hexane) 13 8-140 ⁰ C, chromatographed.

Analysis for C ₁₃ H ₁₂ F ₂ N ₆ O:

calculated: found:

C 50.98 H 3.95 N 27.44 C 51.33 H 4.05 N 27.08

H-NMR, IR and mass spectral data were consistent with the required structure. By chromatographic procedure, the desired product of 1 - / "2- (2,4-di-fluorophenyl) -2-hydroxy-3- (4H-1,2,4-triazol-4-yl) -propyl / -1H- 1,2,4-triazole as an impurity in the reaction mixture separated.

Example 2

(A) Preparation of 2-chloro-2 ', 4'-difluoroacetophenone

FO

+ ClCH ₂ COCl>

C-CH ₂ Cl

Chloroacetyl chloride (113 g, 1.0 mol) was added to a stirred mixture of 1,3-difluorobenzene (114 g, 1.0 mol) and anhydrous aluminum chloride (146.6 g, 1.1 mol) at room temperature (20 ^° C.) dripped). The mixture was further 5 hours

the stirred at 50 to 55 ⁰ C. Methylene chloride (48.5 mL) was slowly added dropwise, allowing the mixture to cool to room temperature. The methylene chloride layer was separated, washed with (2 x 320 ml) of water and the solvent removed by distillation under reduced pressure to leave a pale yellow solid (180 g).

A portion of the crude product (145 g) was prepared from n-hexane (435 ml) crystallized to give the title compound (113 g, 73%), mp 47 - 49 ° C gave (lit. ⁺ 46.5 ⁰ C).. IR (KBr) and NMR o) were consistent with the desired structure.

By D. Ehlers, H. Bercher and A. Grisk, J. Prakt. Chem. 315, 1169 (1973)

(B) Preparation of 2 ', 4'-difluoro-2- (1H-1,2,4-triazol-1-yl) acetophenone hydrochloride

^C " ^CH 2 ^C1

To a mixture of 1,2,4-triazole (30.4 g, 0.44 mol) and triethylamine (15.1 g, 0.15 mol) in refluxing ethyl acetate (186 ml) was added a solution of 2-chloro Added 2 ', 4'-difluoroacetophenone (38.1 g, 0.2 mol) in ethyl acetate (80 ml). The mixture was refluxed for 6 hours, then cooled to room temperature and the insoluble fractions filtered off. The filtrate was washed with (2 × 200 ml) of water and then the solvent was removed by distillation under reduced pressure. The crude product was dissolved in (150 ml) ethyl acetate, then 25% (w / v) HCl gas in isopropanol was added. The mixture was granulated at 0 ^° C. for 1 hour and then the solid was collected by filtration and added to

"4

Title compound (21.6 g, 40%), mp 167-170 ⁰ C, dried. IR (KBr) and NMR (DMSO) were consistent with the desired structure.

This intermediate was characterized as the free base prepared by the following technique:

To a stirred slurry of sodium bicarbonate (16.8 g, 0.2 mol) and 1,2,4-triazole (27.6 g, 0.4 mol) in refluxing toluene (180 mL) was added a solution of 2- Chloro-2 ', 4'-difluoroacetophenone (38.1 g, 0.2 mol) in toluene (4 5 ml). The mixture was stirred at reflux for 3 hours and the water formed during the reaction was removed with a Dean-Stark trap. The reaction mixture was cooled to room temperature and then (180 ml) of water was added. The toluene layer was separated and the solvent was removed by distillation under reduced pressure. The resulting pale brown solid was recrystallized from 1: 1 ethyl acetate / n-hexane (70 ml) crystallized to give the title compound (3.9 g), mp Ίθ3 - to give 105 ⁰ C,.. IR (KBr) and NMR (CDCl.,) Were consistent with the desired structure.

Analysis for C H ₇ F ₃ N 0,%:

Calculated: C 53.8 H 3.16 N 18.82 Found: C 53.62 H 3.15 N 18.68

(C) Preparation of 1- / 2- (2,4-difluorophenyl) -2,3-epoxypropyl / -1H-1,2,4-triazole methanesulfonate

.HCl

.CH ₃ SO ₃ H

24CH7

2 ¹ , 4 ¹ -difluoro-2- (1H-1,2,4-triazol-1-yl) acetophenone hydrochloride (59.6 g, 0.23 mol), trimethylsulfoxonium iodide (50, 6g, 0.23 mol ) and cetrimide (2.1 g) were dissolved in a mixture of toluene (370 ml) and 20 wt / vol. -% aqueous sodium hydroxide stirred at 60 ° for 3 hours. The toluene layer was separated and concentrated to 110 ml, then diluted with ethyl acetate (150 ml). A solution of methanesulfonic acid (16.6 g, 0.172 mol) in ethyl acetate (20 ml) was added. More ethyl acetate (100 ml) was added and the mixture stirred at 0 ⁰ C for 1 hour, then returned filtration of the precipitate the title compound (43 g, 56%).

20 g of the crude product were dissolved in hot, technical methylated spirit (140 ml) and (2 g) carbon added. The mixture was filtered and the filtrate was concentrated to 100 ml, then the mixture was stirred at 0 ^° C. for 1 hour. Filtration gave the title compound (7.8 g, 39%), mp. 128-129 ⁰ C. IR (KBr) and NMR (DMSO) .stimmten with the desired structure.

Analysis for

Calculated: C 43.2 H 3.9 N 12.6 Found: C 42.83 H 3.92 N 12.96

(D) Preparation of 2- (2,4-difluorophenyl) -1,3-bis (1H-1,2,4-triazol-1-yl) -propan-2-ol

.CH ₃ SO ₃ H

L ·

1- / 2- (2,4-Difluorophenyl) -2,3-epoxypropyl / -1H-1,2,4-triazolemethanesulphonate (6.7 g, 0.02 mol), 1,2,4-triazole (2 , 8 g, 0.04 mol) and anhydrous potassium carbonate (9.1 g, 0.066 mol) were stirred in dimethylformamide (35 ml) at 90 ^° C. for 4.5 hours. The mixture was cooled to room temperature, then poured into (170 ml) water. The mixture was extracted with (2 x 60 ml) chloroform and the extracts combined and washed with (2 x 100 ml) water. The chloroform solution was dried over MgSO 4, and the solvent was removed by distillation under reduced pressure to leave the crude product (5.3 g).

The crude product was dissolved in isopropanol (50 ml) and (0.5 g) carbon added. The mixture was filtered and the filtrate concentrated to 2 to 5 ml. The precipitate was collected and the title compound (2.6 g, 4 4%) mp. 13 9-140 ⁰ C, dried. IR (KBr) and NMR (DMSO) were consistent with the desired structure.

Analysis for C ₁ H ₁ -FN O:

Calculated: C 51.0 H 3.92 N 27.5 Found: C 50.85 H 3.92 N 27.74

Claims (4)

PLC. 326 / A / B (PC: 6420) Claim for invention 1. A process for preparing a compound of formula ce N is N-CH ₀ -C-CH ₀ -NN ^(I) or a pharmaceutically acceptable salt thereof, characterized in that 1,2,4-triazole with a compound of formula 43 5 - (VI) or with an acid addition salt thereof, and then optionally converting the product of formula (I) into a pharmaceutically acceptable salt. 2. A process for the preparation of a compound of formula (I) according to item 1, characterized in that a compound of formula wherein Q is a light leaving group, reacted with 1,2,4-triazole and then optionally converting the product of formula (I) into a pharmaceutically acceptable salt.   3. The method according to item 2, characterized in that it is carried out for Q meaning Cl or Br. 4. The method according to item 1, 2 or 3, characterized in that it is carried out in the presence of a base.