Method for treating microbial infections

Abstract

Disclosed herein are 2-aminoalkyl-3-aryl-hetero-indenes useful as antimicrobial agents.

Description

The antimicrobial compounds of the invention are 2-aminoalkyl-3-aryl-hetero-indenes of the formula: ##SPC1##

Wherein n is 0 or 1: R.sub.2 is hydrogen or amino lower alkylene having 1 to 3 carbon atoms; R.sub.1 is carbonyl or lower alkylene having 1 to 3 carbon atoms with the provisio that when R.sub.2 is hydrogen, R.sub.1 is lower alkylene; T is NH, S or O; X is halogen, nitro, or trifluoromethyl; Y is hydrogen, halogen, methyl or trifluoromethyl; M is hydrogen, halogen or methyl with the provisio that when X is nitro, M is halogen; Z is hydrogen, halogen, nitro or methyl; and the acid addition salts thereof.

"Heteroindene", as used herein, is an indene wherein the carbon atom in the 1-position is replaced by a hetero atom selected from NH, S, or O, i.e. indole, benzothiophene and benzofuran, respectively.

As used herein the term "lower alkylene" refers to methylene, ethylene, propylene, and ispropylene and cyclopropylene. The term "halogen" as used herein comprehends fluorine, chlorine, bromine and iodine. Chloro is the preferred X substituent. A preferred location on the indole ring for the X moiety is the 5-position. Preferably M is ortho-halo, with ortho-fluoro or ortho-chloro being especially preferred. T is preferably NH although it may be S or O. The term "amino lower alkylene" refers to radicals represented by the formula --R.sub.3 --NH.sub.2 wherein R.sub.3 is lower alkylene as defined above. n preferably is O.

A particularly useful group of anti-microbial 2-aminoalkyl-3-phenyl-hetero-indenes within formula I has the formula: ##SPC2##

Wherein n is 0 or 1, X is halogen or trifluoromethyl, M is hydrogen, bromo or chloro, and one of Y and Z is 2-fluoro or 2-chloro and the other is hydrogen, halo, nitro or trifluoromethyl. It is particularly desireable for the M,Z-substituted phenyl group to be 2-fluorophenyl, 2,6-difluorophenyl, or 2,4-dichlorophenyl.

Particularly preferred compounds within this group include:

2-aminomethyl-5-chloro-3-(2-fluorophenyl)indole, 2-aminomethyl-5-chloro-3-(2,6-difluorophenyl)indole, 2-aminomethyl-5-chloro-3-(2,6-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5,7-dichloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5,6-dichloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-6-chloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-6-bromo-3-phenylindole, and 5,6-dichloro-3-(2,4-dichlorophenyl)indole-2-(N-.beta.-aminoethyl)carboxamide.

Other particularly interesting compounds within formula I include:

2-(1-aminoethyl)-5-chloro-3-phenylindole, 2-(1-aminoethyl)-5-chloro-6-bromo-3-phenylindole, 2-aminomethyl-5-chloro-3-(benzyl)indole, 2-aminomethyl-5-chloro-3-(3,4-dichlorophenyl)indole, and 2-[N-(.beta.-aminoethyl)aminoethyl]-5-chloro-3-phenylindole hydrochloride.

The acid addition salts can sometimes be used more conveniently than the indenes themselves; for example, because the salts have more convenient physical properties such as crystalline form or solubility, or because the salts are more readily purified by recrystallization, than the indenes. When the salts are used in food or medicine, the anion must, of course, be substantially non-toxic at the concentration or dosage used; when the salts are used in technical fields such as the preservation of paper, leather, or photographic goods, the anion need not necessarily be non-toxic.

Although some of the compounds of formula II have been proposed as intermediates in the preparation of benzodiazepines, many are novel; in particular, compounds in which M is halogen and/or Y and Z are not hydrogen are novel. Novel compounds within formula I include:

2-aminomethyl-5-chloro-3-(2,6-difluorophenyl)indole, 2-aminomethyl-5-chloro-6-bromo-3-phenylindole, 2-aminomethyl-5-chloro-3-(2,4-dichlorophenyl)indole, 2-(1-aminoethyl)-5-chloro-6-bromo-3-phenylindole, 2-aminomethyl-5,7-dichloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5,6-dichloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(3,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(2,4-dichlorophenyl)-6-nitroindole, 2-aminomethyl-6-chloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-iodo-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-trifluoromethyl-3-(2,4-dichlorophenyl) indole, 2-aminomethyl-6-chloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(3,4-dimethylphenyl)indole.

Still other compounds within the formula I are:

2-aminopropyl-7-iodo-3-(3-nitrophenyl)indole,

2-(2'-aminopropyl)-5-trifluoromethyl-3-(2-fluoro-4-nitrophenyl)indole,

2-aminomethyl-3-(2-nitrophenyl)indole, 2-aminopropyl-7-bromo-3-(2-trifluoromethylphenyl)indole.

The 2-aminoalkyl-3-phenylindenes of the formula II and their acid addition salts can be prepared by standard methods, known for the preparation of substituted indenes or of amines; for example, processes disclosed in the following literature: U.S. Pat. Nos. 3,697,508; 3,558,604 and 3,558,603; Belgian Pat. No. 724,993; and "Benzodiazepines", Inaba, Ishizumi and Yamamoto, Chem. Pharm. Bull., 19(2), pages 263-272 (1971).

The 3-phenylindole nucleus itself is normally most conveniently obtained by a Fischer indole synthesis, or by an equivalent reaction in which a benzenediazonium salt reacts with an ester of a 2-benzylacetoacetic acid in the presence of alkali and the product is cyclised by heating in the presence of acid or in ethylene glycol. Further modifications, especially transformation of the substituent at the 2-position, and/or removal of a blocking or protecting group at the 1-position, may then be effected.

The 2-aminoalkyl-3-phenylbenzo [b] thiophenes can be prepared from methyl 3-phenylbenzo [b] thiophene-2-carboxylate, known from Krubsack and Higa in Tetrahedron Letters No. 47, page 4823 (1972), by standard methods. The 2-aminoalkyl-3-phenylbenzo [b] furans can be prepared from 2-cyano-5-chloro-3-phenylbenzofuran, known from standard methods.

Typical final steps are, reduction of a precursor compound of the formula: ##SPC3##

wherein Q is a group directly reducible to R.sub.1 NHR.sub.2. The reduction can be effected by catalytic hydrogenation, by lithium aluminium hydride; electrolytically, etc.

A cyano group Q is most conveniently reduced with a boron hydride, especially borane, or with a complex metal hydride such as lithium aluminium hydride, calcium borohydride, or sodium borohydride in the presence of aluminium chloride or of boron trifluoride. The inert solvent will normally be an ether solvent, e.g., diethyl ether, tetrahydrofuran or dioxan. Compounds in which Q is a cyano group may also be reduced electrolytically.

Other suitable Q groups are carbamoyl or thiocarbamoyl, nitro alkyl, an oxime, ether or ester thereof, a ketimine, a hydrazine, or a semicarbazone.

Indenes wherein R.sub.2 is an amino lower alkylene may be prepared by reaction of the corresponding carboxylate with the appropriate amine.

The 2-aminoalkyl-3-phenyl-heteroindenes may be isolated from the foregoing processes as the free bases or as acid addition salts or may be interconverted into acid addition salts e.g., hydrochlorate, sulfurate, nitrate, phosphate, acetate or succinate, phenolate and the like. The acid may be so chosen as to additionally impart activity, e.g. hexylresoicinol, to enhance the antimicrobial spectrum.

The following examples illustrate the preparation of compounds of the formula I; Example 1 shows the preparation of a preferred compound by the standard reduction of the corresponding nitrile with lithium aluminium hydride, whereas Example 2 illustrates a slightly different final step and also the preparation of the appropriate precursors. Examples 3 and 4 illustrates the most preferred compounds of the invention. Examples 5 and 6 respectively illustrate a thiophene and furan compound according to the invention, while Example 7 illustrates a preferred indole wherein R.sub.2 is an amino lower alkylene.

EXAMPLE 1

2-Aminomethyl-5-chloro-3-(2-fluorophenyl)indole

Add a solution of 7.5 g. (0.0277 mol) of 5-chloro-3-(2-fluorophenyl)indole-2-carbonitrile in 100 ml. of dry ether to a stirred suspension of 1.25 g. (0.033 mol) of lithium aluminium hydride in 200 ml. of dry ether. Reflux the reaction mixture for 4 hours. Cool to room temperature and slowly add 3 ml. of water to quench the reaction. Filter the mixture and dry overnight over magnesium sulfate.

Filter the solution, evaporate to dryness and recrystallize the residue from a mixture of methylene chloride and petroleum ether to give the title compound. The hexylresorcinol salt melts at 150.degree.-152.degree.C.

EXAMPLE 2

2-Aminomethyl-5-chloro-3-(2,6-difluorophenyl)indole

Step A: N-[2-(2,6-difluorobenzoyl)-4-chloro]-phenylglycinonitrile A mixture of 5 g. (0.0186 mol) of 2-amino-5-chloro-2',6'-difluorobenzophenone, 3.9 g. (0.06 mol) of potassium cyanide and 2.8 g. (0.093 mol) of paraformaldehyde is treated with 25 ml of glacial acetic acid saturated with dry hydrogen chloride. The mixture is refluxed for 15 minutes, then poured onto 800 ml of ice water. The resulting precipitate is filtered off, washed with water and recrystallized from methanol (m.p. 175.degree.-176.degree.). Recrystallization affords yellow needles; m.p. 182.degree.-183.degree. .

Step B: 5-chloro-3-(2,6-difluorophenyl)indole-2-carbonitrile A solution of N-[2-(2,6-difluorobenzoyl)-4-chloro]phenylglycinonitrile (2.0g) in 20 ml of dry tetrahydrofuran is treated with a large excess (4 ml) of trifluoroacetic anhydride. The mixture is refluxed for 4hours, and solvent and excess of reagent are removed under vacuum. The residue is twice treated with dry tetrahydrofuran and each time evaporated to dryness. Finally, the residue is again dissolved in dry tetrahydrofuran and treated with 1 g of sodium hydride (57% in mineral oil).

The mixture is refluxed for one hour, cooled to room temperature and poured into a mixture of ice, water and chloroform. The organic layer is separated, water with water and dried over magnesium sulfate. Filtration and evaporation yield a semisolid, which is filtered through silica gel to give the title compound; m.p. 199.degree.-200.degree..

Step C: 2-aminomethyl-5-chloro-3-(2,6-difluorophenyl)indole

Borane in tetrahydrofuran (7 ml of a 1M solution) is added to a solution of 1 g (3.46 mmol) of 5-chloro-3-(2,6-difluorophenyl)indole-2-carbonitrile in 15 ml of dry tetrahydrofuran. The solution is stirred at room temperature for 2 hours and then refluxed for half an hour and cooled to room temperature. 5 ml of 5N aqueous HCl is added dropwise and the mixture is refluxed for 20 minutes. The mixture is then poured onto a mixture of ice and aqueous 10 percent ammonia, and the precipitate is extracted with chloroform. The chloroform layer is washed with water and dried over magnesium sulfate, filtered and evaporated to dryness. Recrystallization from chloroform (charcoal) affords colorless crystals; m.p. 212.degree.-214.degree. .

EXAMPLE 3

2-Aminomethyl-6-bromo-5-chloro-3-phenylindole

Step A: Ethyl 6-bromo-5-chloro-3-phenylindole-2-carboxylate

All 11 ml (33 g.) of bromine to a mixture of ethyl 5-chloro-3-phenylindole-2-carboxylate (30 g.) in 100 ml of acetic acid at 10- 20.degree.. Stir overnight and then add a solution of sodium bisulfite. Filter and wash the precipitate with water. Stir the solid with methanol and filter to yield the title compound. Recrystallization from methanol yields the analytical sample; m.p. 205.degree.-206.degree.C.

Step B: 6-Bromo-5-chloro-3-phenylindole-2-carboxylic acid

Reflux the ester (13 g.) of step A in 100 ml of ethanol with 150 ml of 10% sodium hydroxide solution for 2 hours. Evaporate off most of the methanol and, after cooling the mixture, add 5% hydrochloric acid. Collect the precipitate and dry to obtain the title compound; m.p. 241.degree.-242.degree.C.

Step C: 6-Bromo-5-chloro-3-phenylindole-2-carboxamide

Mix the acid (6 g.) of step B with 20 ml of thionyl chloride and boil under reflux for 0.5 hour. Evaporate the solution to dryness. Add tetrahydrofuran and evaporate twice to remove any remaining thionyl chloride. Add tetrahydrofuran (80 ml) and bubble ammonia gas through the solution. Add water to dissolve the precipitate at which time an oil separates. Add methanol to the oil to yield crystals which are collected and dried to yield the title compound.

Step D: 6-Bromo-5-chloro-3-phenylindole-2-carbonitrile

Reflux the amide (4.5 g.) of step C with phosphorous oxychloride (20 ml) for two hours. Cautiously pour the mixture, while still hot, onto ice-water. Collect the precipitate and dry to yield the title compound.

Step E: 2-Aminomethyl-6-bromo-5-chloro-3-phenylindole

Reflux the nitrile (10 g.) of step D in 100 ml of 1 molar borane in tetrahydrofuran for 4 hours, cool and then cautiously add 7 ml of concentrated hydrochloric acid. Evaporate the solution and add 5% sodium hydroxide with stirring. Collect the solid, dissolve in ethanol and precipitate with water. Collect and dry the precipitate to yield the title compound. Recrystallize from benzene; m.p. 162.degree.-163.degree.C. The hydrochloride melts at 202.degree.-204.degree.C.

EXAMPLE 4

2-Aminomethyl-5-chloro-3-(2,4-dichlorophenyl)indole

Step A: N-[2-(2,4-dichlorobenzoyl)-4-chloro]phenylglycinonitrile

Mix together 2-amino-2',4',5-trichlorobenzophenone (5 g.), potassium cyanide (3.25 g.), and paraformaldehyde (2.5 g.). Then add 12.5 ml of acetic acid saturated with hydrogen chloride and 12.5 ml of acetic acid. Keep the temperature below 70.degree. for several minutes and then boil under reflux for 5 minutes. Cool and pour onto ice-water. Collect the precipitate and extract with chloroform. Treat this solution with sodium carbonate solution and then water and finally dry (MgSO.sub.4). Evaporate to yield the title compound. Recrystallize from methylene chloride-petroleum ether; m.p. 166-167.degree..

Step B: 5-Chloro-3-(2,4-dichlorophenyl)indole-2-carbonitrile

Dissolve the glycinonitrile of step A (40 g.) in 175 ml of dry tetrahydrofuran. Add 50 ml of trifluoroacetic anhydride. Boil under reflux overnight. Remove the solvent under nitrogen. Add more solvent and remove twice. Dissolve the crystalline residue in tetrahydrofuran, and treat with 20 g. of 57% sodium hydride in mineral oil. Boil under reflux for 30 minutes and pour onto icewater. Stir and collect the solid. Wash with water, dry and wash with petroleum ether. Crystallize from methylene chloride-petroleum ether to obtain the title compound; m.p. 181.degree.-182.degree. .

Step C: 2-Aminomethyl-5-chloro-3-(2,4-dichlorophenyl)indole

Dissolve the nitrile (22 g.) of step B in a mixture of 137 ml of 1 molar borane in tetrahydrofuran and 100 ml of tetrahydrofuran and stir for 4 hours. Boil under reflux for 0.5 hour, cool and add 5 N hydrochloric acid. Boil under reflux for 1 hour and pour onto a mixture of ice and 10% ammonia. Extract with chloroform, wash and dry (MgSO.sub.4). Evaporate to yield the title compound. Crystallize from ether-petroleum ether to obtain the analytical sample; m.p. 179.degree.-180.degree.. To prepare the hydrochloride salt, dissolve this material in ethanol, add concentrated hydrochloric acid, collect and dry the material; m.p. 226.degree.-228.degree..

EXAMPLE 5

2-Aminomethyl-5-bromo-3-phenylbenzo[ b]thiophene hydrochloride

Step A: Methyl 5-bromo-3-phenylbenzo[ b]thiophene-2-carboxylate

Add 29.3 g. bromine (10 ml; 0.37 mole) to 8.0 g. (0.03 mole) of methyl 3-phenylbenzo [b]thiophene-2-carboxylate in 100 ml. of acetic acid and stir the mixture overnight at room temperature. Add a saturated solution of sodium bisulfite. Decant the supernatant and wash the oil with water. Triturate with methanol. Recrystallize from methanol to yield the title compound; m.p. 125.degree.-126.degree..

Step B: 5-Bromo-3-phenylbenzo[ b]thiophene-2 -carboxylic thiophene-

Heat three grams of methyl 5-bromo-3-phenylbenzo[ b]thiophene-2-carboxylate in a mixture of 50 ml. of methanol and 30 ml. of 10% sodium hydroxide, under reflux for one hour. Add concentrated hydrochloric acid to yield the title compound as a precipitate. Recrystallize from benzene; m.p. 265.degree.-266.degree..

Step C: 5-Bromo-3-phenylbenzo[ b]thiophene-2-carboxamide

Reflux 2.8 g. 5-bromo-3-phenylbenzo[b]thiophene-2-carboxylic acid (0.0084 mole) and 10 ml. of thionyl chloride in 15 ml. of dry tetrahydrofuran for one hour, evaporate to dryness, add 50 ml. of tetrahydrofuran twice and evaporated each time to dryness. Dissolve solid in 70 ml. of tetrahydrofuran, cool to about 10.degree. and add with stirring 10 ml. of concentrated ammonia. The title compound is obtained as a white solid; m.p. 201.degree.-202.degree..

Step D: 5-Bromo-2-cyano-3-phenylbenzo[ b]thiophene

Reflux 2.1 g. 5-bromo-3-phenylbenzo[ b]thiophene-2-carboxamide (0.0063 mole) together with 10 ml. of phosphorus oxychloride for 11/2 hours and then carefully pour onto ice water. Filter off the white precipitate. Dry. Recrystallize the title compound from methanol; m.p. 145.degree.-146.degree..

Step E: 2-Aminomethyl-5-bromo-3-phenylbenzo[ b]thiophene hydrochloride

Treat 1.4 g. 5-bromo-2-cyano-3-phenylbenzo[ b]thiophene (0.0045 mole) in 40 ml of tetrahydrofuran, with 10 ml of 1 molar borane in tetrahydrofuran. Reflux the solution for 11/2 hours. Slowly add 10 ml of 5% hydrochloric acid. Heat the mixture for 1/2 hour, cool and add sufficient sodium hydroxide solution to basicity. Extract the solution with ether and wash twice with water. Dry the ether layer (MgSO.sub.4), filter and mix with 50 ml of ether saturated with hydrogen chloride. Dry the precipitate to yield the title compound; m.p. over 225.degree. (decomp).

EXAMPLE 6

2-Aminomethyl-5-chloro-3-phenylbenzofuran hydrochloride

Treat 2.0 g. 2-cyano-5-chloro-3-phenylbenzofuran (0.008 mole) in 30 ml of tetrahydrofuran with 18 ml of borane in tetrahydrofuran (1 m solution). Reflux for 2 hours. Cool, add 10 ml of 10% hydrochloric acid and reflux for 1/2 hour. Evaporate the solution to dryness. Dissolve the residue in 50 ml of ethanol. Add 30 ml of ethanol saturated with hydrogen chloride. Dry the precipitate obtained to yield the title compound; m.p. 254.degree.-256.degree..

EXAMPLE 7

5,6-dichloro-3-(2,4-dichlorophenyl)indole-2-N-(.beta.-aminoethyl)carboxamide

Step A: Ethyl 5,6-dichloro-3-(2,4-dichlorophenyl)indole-2-carboxylate

Prepare a solution of 3,4-dichlorophenyl-diazonium chloride by treating 8.2 g. of 3,4-dichloroaniline in 25 ml of concentrated hydrochloric acid with a solution of 3.5 g. of sodium nitrite in 35 ml of water at -5.degree.. Dissolve ethyl 2-(2,4-dichlorobenzyl) acetoacetate (14.3 g.) in 100 ml of ethanol with 8.3 g. of potassium hydroxide in 8.3 ml of water and cool to -5.degree.. Add the solution of the diazonium salt to the latter solution, keeping the temperature at 0.degree., and stir for 15 minutes. Extract with ether and wash the ether solution with two 75 ml portions of 5% sodium hydroxide and then with water and dry (MgSO.sub.4). Evaporate to yield the intermediate: ethyl 2,4-dichlorophenylpyruvate 3,4-dichlorophenyl hydrazone. The analytical sample is obtained from ethanol; m.p. 160.degree.-161.degree.. Dissolve the hydrazone (125 g.) in 700 ml of 20% ethanolic sulfuric acid and boil under reflux for 2 hours. Cool to room temperature and collect the crystalline product. Wash with 50% aqueous alcohol. Recrystallize from ethanol; m.p. 230.degree.-231.degree. .

Step B: 5,6-dichloro-3-(2,4-dichlorophenyl)indole-2-N-(.beta.-aminoethyl)carboxamide

Boil a mixture of 1.0 g. of ethyl 5,6-dichloro-3-(2,4-dichlorophenyl)indole-2-carboxylate, 1 ml of ethylene diamine and 5 ml of dry toluene under reflux for 24 hours. Then cool the mixture to room temperature, dilute with benzene, wash with water and dry over MgSO.sub.4. Filter off the MgSO.sub.4 and evaporate off the solvent to yield a solid residue, which upon crystallization from CHCl.sub.3 -petroleum ether gives the title compound; 600 mg; m.p. 216.degree.-218.degree..

The following compounds may be prepared in a final step similar to that of Examples 1-7:

2-(1-aminoethyl)-6-bromo-5-chloro-3-phenylindole, 2-aminomethyl-5,7-dichloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5,6-dichloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(3,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(2,4-dichlorophenyl)-6-nitroindole, 2-aminomethyl-6-chloro-3-(2,4-dichlorophenyl)-5-fluroindole, 2-aminomethyl-3-(2,4-dichlorophenyl)-5-iodoindole, 2-aminomethyl-3-(2,4-dichlorophenyl)-5-trifluoromethylindole, 2-aminomethyl-6-chloro-3-(2,4-dichlorophenyl)indole, 2-aminomethyl-5-chloro-3-(2,4-dichlorophenyl)-6-methoxyindole, 2-aminomethyl-5-chloro-3-(2-fluorophenyl)benzo[b]thiophene, 2-aminomethyl-5,6-dichloro-3-(2-fluorobenzyl)benzo[b]thiophene, 2-aminomethyl-6-bromo-3-(2,6-dichlorobenzyl)benzofuran, 2-aminomethyl-3-(2-chloro-6-methyl-phenyl)indole, 2-aminomethyl-5-chloro-3-(3,4-dimethylphenyl)indole, 2-aminomethyl-5,6-dichloro-3-(2,4 dichlorophenyl)benzo[ b]thiophene, 2-aminoethyl-5-iodo-3-(2,4 dichlorophenyl)benzo[b]thiophene, 2-aminomethyl-3-(2-chloro-6 methyl-benzyl)benzo[ b]thiophene, 2-aminomethyl-5-chloro-3-(2,4 dimethylphenyl)benzofuran, 2-aminomethyl-5-chloro-3-(2-chloro-6-trifluoromethylbenzyl)benzofuran, 2-aminomethyl-5-chloro-7-iodo-3-phenylbenzofuran hydrochloride, 5-chloro-3-(2-fluorophenyl)indole-2-N-(.beta.-aminoethyl) carboxamide, 5,6-dichloro-3-(2,6-difluorophenyl)indole-2-N-(.beta.-aminoethyl)carboxamide, 5,6-dichloro-3-(2,4-dichlorobenzyl)indole-2-N-(.beta.-aminoethyl)carboxamide, and 2-[N-(.beta.-aminoethyl)aminoethyl]-5-nitro-3-(2,4-di-trifluoromethylphenyl)indole.

The compounds of formula I and their non-toxic acid addition salts can be used to treat diverse types of susceptible microbial infections. Furthermore, they are capable of preserving a wide variety of preparations including medical, veterinary, cosmetic and food preparations from microbial contamination; a stabilizing amount of such a compound is incorporated in the preparation in which the preservation is desired.

Susceptibility can be readily determined by standard in vivo and in vitro tests well known to the microbiologist. Genera of susceptible microorganisms include bacteria, fungi, and protozoa.

Exemplifying susceptible bacterial microorganisms are Staphylococcus aureus, Streptococcus pyogenes C., Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. Susceptible fungi include Candida albicans, Trichophyton mentagrophytes and Saccharomyces cerevisiae. Susceptible protozoal pathogens include Trychomonas vaginalis and Entamoeba histolytica.

Tables I to VII give the results of various in vitro and in vivo tests of representative 2-aminoalkyl-3-phenylindenes of formula II against a variety of microorganisms including bacteria, fungi and protozoa, and also report the toxicity of these 2-aminoalkyl-3-phenylindenes. The compounds of the tests are as follows:

Compound Name______________________________________A 2-aminomethyl-5-chloro-3-(2-fluoro- phenyl)indoleB 2-aminomethyl-5-chloro-3-(2,6-di- fluoro-phenyl)indoleC 2-(1-aminoethyl)-5-chloro-3-phenyl- indoleD 2-aminomethyl-6-bromo-5-chloro-3- phenylindoleE 2-aminomethyl-5-chloro-3-(2,4-di- chlorophenyl)indole______________________________________ All the tests were carried out and (when necessary) scored under standard conditions. "MIC" means "minimum inhibitory concentration."

TABLE I

In vitro Antibacterial Activity of 2-aminoalkyl-3-phenylindoles of the formula I. Dilution in Mueller Hinton Agar pH 7.4

MIC (mcg/ml)Organism Compound A B C D E__________________________________________________________________________Staphylococcus aureus 209P 7.5 7.5 7.5 3.0 3.0 Wood 3.0 7.5 7.5 3.0 3.0 Zeigler 3.0 7.5 3.0 3.0 0.8 Gray 7.5 7.5 7.5 3.0 3.0 59N 3.0 7.5 7.5 3.0 3.0Streptococcus pyogenes C 7.5 17.5 7.5 3.0 3.0 27 7.5 7.5 7.5 3.0 3.0 Cruz 3.0 3.0 3.0 3.0 0.8Enterococcus 373 7.5 7.5 7.5 3.0 3.0 0928/72 7.5 17.5 7.5 3.0 3.0Escherichia coli 10536 7.5 7.5 7.5 3.0 3.0 1574-1 7.5 7.5 3.0 3.0 3.0 777 3.0 7.5 3.0 3.0 3.0 4195 3.0 7.5 3.0 3.0 3.0 JR66 3.0 7.5 3.0 3.0 3.0Klebsiella AD17 7.5 17.5 7.5 3.0 7.5 AD22 7.5 7.5 3.0 3.0 3.0 G3694 7.5 7.5 3.0 3.0 3.0 3020 7.5 7.5 3.0 3.0 3.0 121 7.5 17.5 3.0 3.0 7.5Proteus mirabilis Hard 17.5 17.5 7.5 3.0 3.0Peras 7.5 37.5 7.5 3.0 17.5Proteus rettgeri mirabilis 17.5 17.5 7.5 7.5 17.5Proteus vulgaris Napol 17.5 17.5 7.5 3.0 3.0Proteus morganii Valz 17.5 17.5 7.5 3.0 17.5Pseudomonas aeruginosa 8709 17.5 17.5 17.5 7.5 7.5 762 17.5 17.5 37.5 17.5 17.5 130 17.5 17.5 17.5 17.5 7.5 138 17.5 17.5 17.5 7.5 17.5 Trav. 1 17.5 17.5 17.5 7.5 17.5Salmonella ent. 1 7.5 7.5 7.5 3.0 3.0 C.sub.2 Napo 3.0 7.5 3.0 3.0 3.0 B typhi 7.5 7.5 3.0 3.0 3.0 C.sub.1 Oso 7.5 7.5 3.0 3.0 3.0 C.sub.2 Cuban 7.5 7.5 3.0 3.0 3.0__________________________________________________________________________ TABLE II__________________________________________________________________________In vitro activity of 2-aminoalkyl-3-phenylindoles of the formula Iagainst anaerobes in fluid Thioglycollate mediumMIC (mcg/ml) after 48 and 72 hrsOrganism Compound A B C D E 48 72 48 72 48 72 48 72 48 72__________________________________________________________________________Bacteroides melaninogenicus 7.5 7.5 7.5 17.5 7.5 7.5 3.0 3.0 3.0 3.0Bacteroides fragilis 7.5 7.5 3.0 3.0 3.0 3.0 .75 .75 .75 .75Bacteroides corrodens 7.5 7.5 7.5 7.5 3.0 3.0 .75 .75 .75 3.0Eubacterium lentum 17.5 17.5 17.5 17.5 7.5 7.5 .75 .75 3.0 3.0Clostridium novyi 7.5 7.5 7.5 7.5 3.0 3.0 .75 .75 .75 .75Clostridium septicum 7.5 7.5 3.0 3.0 3.0 3.0 .75 .75 .75 .75Clostridium histolyticum 7.5 7.5 7.5 7.5 3.0 3.0 .3 .3 .3 .3Peptostreptococcus 3.0 3.0 3.0 3.0 3.0 3.0 .3 .3 .75 .75__________________________________________________________________________

TABLE III

In vitro Anti-Candida Activity of 2-aminoalkyl-3-phenylindoles of the formula I. Dilutions in Sabouraud's Dextrose Agar

MIC (mcg/ml) after 48 hours CompoundCandidaalbicans A B C D E______________________________________Burke 75 75 75 150 37.5Lusk 75 75 75 75 37.5Blunden 75 75 75 17.5 37.5Fix 75 75 75 75 37.5Collins 75 75 75 75 37.5Merkel 75 75 75 75 37.529 75 75 37.5 75 37.5Wisconsin 75 150 75 150 37.5Sparks 75 150 75 150 37.5Bevan 75 150 75 150 37.5Newcomb 37.5 37.5 37.5 17.5 17.5Kennedy 1 37.5 75 37.5 17.5 37.5Pannell 75 75 75 75 17.5Atkisson 75 75 75 150 37.51 75 150 75 150 37.52 75 75 75 150 37.53 75 150 75 75 37.54 75 75 37.5 37.5 17.55 75 75 75 75 17.56 75 150 75 150 37.58 75 150 75 150 37.59 75 75 75 150 37.5Burnside 75 150 75 75 37.5Lehtman 75 150 75 150 37.5Fulcher 75 75 75 75 37.5Shurelli 75 150 75 150 37.5Frazier 75 150 75 150 37.5Boyer 75 150 75 150 37.5Sherod 75 150 75 150 37.5Bognay 75 75 75 75 37.5Johnson 75 150 75 150 37.5Gay 75 150 75 150 37.5Tyner 75 150 75 75 37.5Kennedy 2 75 150 75 150 37.5Bertrand 75 150 75 150 37.5Hons 75 150 75 150 37.5______________________________________

TABLE IV

In vitro Antifungal Activity of 2-aminoalkyl-3-phenylindoles of the formula I against Dermatophytes and Aspergillus. Dilutions in Sabouraud's Dextrose Broth.

__________________________________________________________________________MIC (mcg/ml) after 96 hours CompoundFungi A B C D E__________________________________________________________________________Trichophyton ascoides 17.5 17.5 7.5 7.5 7.5 discoides 7.5 17.5 17.5 7.5 7.5 ferrugineum 7.5 37.5 17.5 17.5 7.5 gallinae 7.5 7.5 37.5 75.0 17.5 megninii 3.0 7.5 7.5 3.0 3.0 mentagrophytes A 7.5 7.5 7.5 7.5 3.0 mentagrophytes B 7.5 7.5 7.5 3.0 17.5 mentagrophytes C 7.5 7.5 3.0 3.0 17.5 mentagrophytes Young 7.5 7.5 7.5 7.5 3.0 mentagrophytes H377 7.5 17.5 17.5 7.5 7.5 rubrum Blehl 7.5 17.5 37.5 7.5 3.0 rubrum 3 7.5 17.5 17.5 3.0 3.0 rubrum Haggerty 7.5 17.5 7.5 7.5 3.0 rubrum 360 7.5 17.5 7.5 3.0 3.0 schoenleinii 17.5 17.5 17.5 7.5 3.0 schoenleinii 2 3.0 7.5 3.0 7.5 3.0 soudenense 17.5 17.5 17.5 3.0 7.5 tonsurans 17.5 200.0 7.5 17.5 7.5Tricoderm sp. 7.5 7.5 7.5 7.5 3.0Microsporum nanum 3.0 17.5 3.0 3.0 3.0Microsporum distortum 3.0 17.5 7.5 3.0 3.0Epidermophyton floccosum 3.0 17.5 17.5 7.5 3.0Aspergillus sp. No. 3 17.5 37.5 17.5 17.5 17.5Aspergillus niger 6275 17.5 37.5 17.5 17.5 17.5__________________________________________________________________________

TABLE V

Acute Toxicity of 2-aminoalkyl-3-phenylindoles of the formula I in mice.

______________________________________Acute LD.sub.50 (mg/kg)Compound I.P. S.C. Oral______________________________________A 250 850 >1000B 225 900 about 1000C 100 600 >1000D 175 750 about 950E 85 540 about 700______________________________________

TABLE VI

Effect of some 2-aminoalkyl-3-phenylindoles of the formula II against topical T. mentagrophytes infections in guinea pigs.

__________________________________________________________________________ Average No. of Days Average Sum of to become negative lesion scoresCompound Concentration Cultures Lesion Days 1-5 Days 1-10__________________________________________________________________________A 1% 6.8 9.0 11.8 16.0" 4% 6.0 8.8 11.2 14.8B 1% 9.6 14.2 11.6 20.0" 4% 5.0 7.2 9.2 10.0C 1% 12.4 14.4 13.0 25.0" 4% 5.6 7.4 10.0 11.8D 1% >22 >22 11.6 29.2" 4% 6.2 8.8 11.8 14.2E 1% >22 >22 12.6 34.2" 4% 6.6 9.2 11.6 15.2Untreatedcontrols >22 >22 14.8 38.2__________________________________________________________________________

TABLE VII

In vitro Anti-Trichomonal Activity of some 2-aminoalkyl-3-phenylindenes of formula II.

______________________________________ Minimal Level (mcg/ml) to ProduceCompound 90% Suppression 50% Suppression______________________________________A 40 24B 75 32C 38 30D 38 20E 28 14______________________________________

The invention, therefore, provides compositions containing, as an active ingredient, a 2-aminoalkyl-3-phenyl-heteroindene of the formula I hereinbefore defined or an acid addition salt thereof, in association with a suitable carrier, excipient or diluent. In its function as active ingredient, the compound of the formula I or salt thereof may be used to preserve the carrier from microbial contamination; for example, the carrier may be cutting or other oil, paper, leather, photographic emulsion, canvas or rope. If the salt is non-toxic, the carrier may also be a food-stuff, food-additive or food-supplement, or a medicinal or cosmetic preparation. Such medicinal or cosmetic preparations may conveniently be in fluid form, e.g., lotions, creams, ointments, solutions, suspensions or aerosol preparations.

When used as preservatives, the compounds of the formula I or their salts are preferably incorporated into the composition to be preserved in an amount of 0.05 to 1% by weight, especially 0.1 to 0.5% by weight.

The compounds of formula I and their non-toxic acid addition salts can themselves be used in medicine as anti-microbial agents, and thus may be formulated as pharmaceutical compositions containing at least one said compound or salt together with a pharmaceutical carrier or excipient. Such a composition may, for example, be in the form of shaped products, in particular dosage units, such as pills, tablets, capsules, dragees, lozenges or suppositories (especially vaginal suppositories). Alternatively, such compositions may be adapted for injection and therefore have as carrier a sterile, pyrogen-free injectable liquid. Injectable compositions will normally be in the form of dosage units; the various dosage units mentioned conveniently contain from 2 to 100 mg., preferably from 5 to 50 mg., of a compound of formula I or non-toxic acid addition salt thereof.

Compositions for oral administration, other than dosage units mentioned above, may be exemplified by powders, granulates, solutions, suspensions, elixirs or aerosols. Compositions for topical application may be exemplified by ointments, creams, lotions, solutions, suspensions, aerosols, gels, shampoos, soaps or dusting powders. The compositions may be adapted in particular as ophthalmic, otic and nasal preparations. Such compositions will normally be based upon standard carriers such as those selected from pharmaceutically acceptable vegetable oils, pharmaceutically acceptable polyalkylene glycols, isopropanol, gelatin, benzyl alcohol, gums, glycerol, petrolatum, preservatives starch, sugars such as lactose, talc, magnesium stearate, aerosol propellants such as chlorofluoroalkanes, and coloring, flavoring, sweetening, thickening, suspending, dispersing, emulsifying, wetting, stabilising and buffering agents.

The composition may also be in the form of an animal feed-stock, feed-additive or feed-supplement.

Compositions in which the active ingredient is a compound of the formula I or non-toxic acid addition salt thereof preferably contain from 0.5 to 10% thereof.

A suitable parenteral dosage range of the compounds of the formula I and non-toxic acid addition salts thereof is about 2 to 10 mg./kg./day. The compounds of formula I and their nontoxic acid addition salts may be formulated into dosage forms as the sole active ingredient or used in association with other ingredients to extend the therapeutic spectrum.

The following formulations exemplify pharmaceutical compositions containing 2-aminoalkyl-hetero-indenes of this invention; the active ingredient illustrated may, of course, be replaced with another compound of formula I or non-toxic acid addition salt thereof, e.g., compound D or E or especially B from the foregoing tests.

______________________________________Formulation 1Topical Cream Per kg.______________________________________2-Aminomethyl-5-chloro-3-phenylindole 10 g. - 100 g.Ethoxylated Cetyl/Stearyl Alcohol 20 g.Cetyl Alcohol 35 g.Stearyl Alcohol 35 g.Petrolatum 200 g.Mineral Oil 50 g.Buffers, Sufficient --Preservatives, Sufficient --Purified Water to make 1.0 kg.______________________________________

Add the cetyl alcohol, stearyl alcohol, ethoxylated cetyl/stearyl alcohol, petrolatum and mineral oil to a suitable mixing vessel. Heat to 80.degree.C. to melt. Mix. Add the preservatives, buffers and 2-aminomethyl-5-chloro-3-phenylindole in approximately 95% of the purified water heated to 80.degree.C. in a suitable mixing vessel. Mix. Add the melted wax phase to the aqueous phase and mix while cooling to about 40.degree.C. Add sufficient purified water to make 1 kg. Mix until cool.

______________________________________Formulation 2Topical Ointment Per kg.______________________________________2-Aminomethyl-5-chloro-3-(2-fluorophenyl)indole 10 g. - 100 g.White Petrolatum, to make 1.0 kg.______________________________________

Melt and heat the petrolatum to 50.degree.C. in a suitable mixing vessel. Remove a portion of the melted petrolatum and make therewith a slurry of the 2-aminomethyl-5-chloro-3-(2-fluorophenyl)indole. Pass the slurry through a suitable colloid mill and mill until a uniform dispersion is obtained. Add the milled slurry to the remainder of the melted petrolatum and mix until cool.

______________________________________Formulation 3Otic Suspension mg/ml______________________________________2-aminomethyl-5-chloro-3-(2-fluorophenyl)indole 5 - 10Cetylpyridinium Chloride, NF 0.20Glyceryl Triacetate 880.0Polyethylene glycol 200 q.s. ad 1.0 ml______________________________________

Melt and heat the petrolatum to 50.degree.C in a suitable mixing vessel. Remove a portion of the melted petrolatum and make a slurry of the 2-aminomethyl-5-chloro-3-(2-fluorophenyl)indole. Pass the slurry through a suitable colloid mill and mill until a uniform dispersion is obtained. Add the milled slurry to the remainder of the melted petrolatum and mix until cool.

______________________________________Formulation 4Vaginal Tablets mg/tablet mg/tablet______________________________________2-Aminomethyl-5-chloro-3-(2-fluorophenyl) indole 10.0 5.0Lactose Hydrous, Impalpable powder 772.0 777.0 USPSodium Lauryl Sulfate 20.0 20.0Polyvinylpyrrolidone 40.0 40.0Corn Starch, Food Grade 150.0 150.0Magnesium Stearate 8.0 8.0 1000 mg 1000 mg______________________________________ Formulation 5Intramuscular or Subcutaneous Oil Injection mg/ml______________________________________2-aminomethyl-5-chloro-3-(2-fluorophenyl)indole 10 - 50Aluminium Monostearate, USP 20.0Sesame Oil, Heat Treated, USP qs ad 1.0 ml______________________________________

Formulations 6 to 8 illustrate compositions preserved with a 2-aminomethyl-3-phenylindole of the formula I:

Formulation 6Lotion mg/ml______________________________________Betamethasone Valerate 1.222-aminomethyl-5-chloro-3-(2-fluorophenyl)indole HCl 1.00Mineral Oil, USP 19.50Diethylene Glycol Monostearate S.E. 6.50Cetostearyl Alcohol 6.50Lanbritol Wax 9.30Glycerin, USP 50.00Isopropanol 65.00Citric Acid 0.08Purified Water, USP, to make 1.00 ml______________________________________ Formulation 7Intramuscular or Intravenous Solution mg/ml______________________________________Gentamicin (charged as sulfate) 40.0Sodium Bisulfite, USP 3.2Disodium Edetate, USP 0.12-aminomethyl-5-chloro-3-(2-fluorophenyl)-indole (charged as the hydrochloride salt) 1-3Water for Injection qs ad 1.0 ml______________________________________ Formulation 8Aerosol Concentrate mg/g______________________________________Megalomicin A Phosphate 20.02-aminomethyl-5-chloro-3-(2-fluorophenyl)indole 1.0Liquid Absorption Base 90.0Stearic Acid 25.0Glyceryl Monostearate 25.0Isopropyl Myristate 50.0Glycerol, USP 100.0Alcohol SD 40 80.0Triethanolamine 10.0Purified Water, USP, to make 1.0 g______________________________________

This composition is packaged into a aerosol container with standard polyfluoroalkane propellant mixtures.

______________________________________Formulation 9Topical Cream Per kg.______________________________________2-Aminomethyl-5-bromo-3-phenylbenzo[b]thiophene hydrochloride 10 g. - 100 g.Stearic acid 60 g.Propylene glycol Monostearate 100 g.Isopropyl Myristate 80 g.Polyoxyethylene (20) SorbitanMonopalmitate 60 g.Sorbitan Solution 20 g.Buffers, Sufficient --Preservatives, Sufficient --Purified Water to make 1.0 kg.______________________________________

Add the stearic acid, propylene glycol monostearate, isopropyl myristate and polyoxyethylene (20) sorbitan monopalmitate to a suitable mixing vessel. Heat to 80.degree.C to melt. Mix.

It is further contemplated that the compounds of the present invention also have herbicidal, insecticidal and other biocidal activity. The compounds may have selective and/or broad base activity depending upon the specific compound within formula I and the specific use for which it is applied.

When used as a herbicide, the compounds may be applied to a stand of crops and weeds in the post-emergence treatment and to the ground in the pre-plant or pre-emergence treatment in a number of ways, well known to the art. The water-soluble compounds, such as the hydrochloride salts, may be sprayed simply as alcoholic/aqueous solutions. The compounds can be deposited as dusts containing a powdered carrier such as talc, attaclay, etc. The compounds having limited water solubility, such as the amine base itself, can be applied as emulsions, the same being formulated as is well known in the art, with commercially available surface-active agents. Among the surface-active agents utilizable are the sulfonated vegetable oils, sodium lauryl sulfate, Tween No. 20 (a polyalkalene ether alcohol), carbowax (polyethylene glycols of M.W. 1500 or more), Atlas G-2122 (polyoxyethylene glycol monolaurate), etc. Penetrants, sequestrants, mineral oils and cosolvents may also be included in the formulations. An example of a suitable formulation is given herein below:

FORMULATION 10

2-amino methyl-5-bromo-3-phenylbenzo[ b]thiophene hydrochoride ethanol.

This ethanol water formulation, when applied on the basis of 4- 8 lbs. of amine base, may be used on a pre-emergence basis against weeds, such as barnyard grass, crabgrass and chickweed.

The compounds may be used as a dusting powder or spray as above described against insects such as ringworm and brown planthopper.

Claims

1. A method for treating susceptible microbial infections, selected from the group consisting of bacterial, fungal and protozoal infections, which comprises administering to an animal species so infected an antimicrobially effective quantity of a compound represented by the formula: ##SPC4## wherein n is 0 or 1; R.sub.2 is hydrogen, or amino lower alkylene having 1 to 3 carbon atoms; R.sub.1 is carbonyl or lower alkylene having 1 to 3 carbon atoms with the provisio that when R.sub.2 is hydrogen, R.sub.1 is lower alkylene; T is NH; X is halogen, nitro, or trifluoromethyl; Y is hydrogen, halogen, methyl or trifluoromethyl; M is hydrogen, halogen or methyl with the provisio that when X is nitro, M is halogen; Z is hydrogen, halogen, nitro or methyl; or the acid addition salts thereof.

2. The method of claim 1, wherein n is O.

3. The method of claim 2, wherein X is chloro.

4. The method of claim 2, wherein R.sub.2 is hydrogen.

5. The method of claim 4, wherein R.sub.1 is methylene.

6. The method of claim 5, wherein said compound is 2-aminomethyl-5-chloro-3-phenylindole.

7. The method of claim 2, wherein said compound is 2-[N-(.beta.-aminoethyl)aminoethyl]-5-chloro-3-phenylindole hydrochloride.

8. The method of claim 1, wherein said compound is 5-aminomethyl-3-benzyl-5-chloroindole.

9. The method of claim 3, wherein X and Y are dihalo.

10. The method of claim 9, wherein said compound is 2-aminomethyl-6-bromo-5-chloro-3-phenylindole.

11. The method of claim 3, wherein M and Z are dihalo.

12. The method of claim 11, wherein M and Z are 2,4-dichlorophenyl.

13. The method of claim 12, wherein said compound is 2-aminomethyl-5-chloro-3-(2,4-dichlorophenyl)indole.

14. The method of claim 12, wherein said compound is 5,6-dichloro-3-(2,4-dichlorophenyl)indole-2-N-(.beta.-aminoethyl)carboxamide.

15. The method of claim 9, wherein M is fluoro.

16. The method of claim 15, wherein said compound is 2-aminomethyl-5-chloro-3-(2-fluorophenyl)indole.

17. The method of claim 1, wherein the microbial infection is bacterial or fungal.