NO150758B - ANALOGY PROCEDURE FOR THE PREPARATION OF THERAPEUTICALLY EFFECTIVE BIS-PYRIDINIUM ALKAN AND XYLENE COMPOUNDS - Google Patents

Description

The present invention relates to the preparation of therapeutically active bis-(4-amino-l-pyridinium)alkane and xylene compounds with therapeutic activity and with the general formula:

where Y is a straight-chain alkylene group of 4-14 carbon atoms or a p-xylene group; R is an alkyl group with 3-12 carbon atoms, cyclohexyl or p-chlorophenyl; and A is an anion;

m is 1 or 3; n is 1 or 2; x is 1, 2 or 3; and (m).(2) = (n).(x); provided that when R is p-chlorophenyl, Y is

a straight-chain alkylene group with 6-14 carbon atoms, and when R

is unsubstituted cyclohexyl, Y is an alkylene group of 8-14 carbon atoms.

These compounds can be used to combat bacteria and fungi and are also active against the herpes virus.

US patent 3,055,902 describes a group of bis-(4-amino-1-pyridinium)alkanes as intermediates for the preparation of the corresponding bis-(4-amino-1-piperidino)alkanes which are stated to have bacteriostatic and bactericidal effects .

W.C. Austin et al., J. Pharm. Pharmacol. 11, 80-93 (1959) describes 1,10-bis-(4-amino-1-pyridinium)decanediiodide and 1,10-bis-(4-acetamido-1-pyridinium)decanediiodide. Certain compounds in the large and widely varying group of quaternary ammonium compounds have been reported to have activity against amoebae, bacteria and parasitic worms, but no biological data have been provided for any of the above compounds.

In formula I, the alkylene group Y can be, for example: 1,4-butylene, 1,5-pentylene, 1,6-hexylene, 1,7-heptylene, 1,8-octylene, 1,9-nonylene, 1,10- decylene, 1,11-undecylene, 1,12-dodecylene, 1,13-tridecylene or 1,14-tetradecylene.

In formula I, where R is a straight or branched alkyl group with from 3-12, preferably 7-9 carbon atoms, the group can e.g. be: n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, 1-methylpentyl, 2,2-dimethylbutyl, 2-methylhexyl, 1,4- dimethylpentyl, 2-ethylpentyl, 3-ethylpentyl, 2-methylheptyl, 1-ethylhexyl, 2-ethylhexyl, 2-propylpentyl, 2-methyl-3-ethylpentyl, 3-ethylheptyl, 1,3,5-tri-methylhexyl, l, 5-dimethyl-4-ethylhexyl, 2-propylheptyl, 5-methyl-2-butylhexyl, 2-propyl-nonyl or 2-butyloctyl.

When A in formula I is an anion, this may include anions of both inorganic and organic acids, e.g. bromide, chloride, fluoride, iodide, sulfate, phosphate, nitrate, sulfamate, methanesulfonate, ethanesulfonate, benzenesulfonate, p-toluenesulfonate, naphthalene sulfonate, naphthalene disulfonate, cyclohexylsulfamate, acetate, trifluoroacetate, malate, fumarate, succinate, tartrate, oxalate, citrate, lactate, gluconate, ascorbate, lactate, phthalate, salicylate, benzoate, picrate, methanephosphonate, arsenite, arsenate, thiosulfate, perchlorate, tartronate, sarcosinate, N-lauroyl sarcosinate, monofluorophosphate, hexafluoroaluminate, hexafluorosilicate, hexafluorostannate, fluorozirconate, tetrafluoroborate, hexachloroplatinate, tetrachloroaluminate, hexachlorostannate. Bromide and chloride are preferred.

According to the present invention, the compounds of formula I are prepared by reacting two moles of a 4-(R-amino)pyridine compound with the formula:

where R has the above meaning, with one mole of a disubstituted alkane compound of the formula: where Y has the above meaning, and Z is chlorine, bromine, iodine, methanesulfonyloxy, ethanesulfonyloxy, benzenesulfonyloxy or p-toluenesulfonyloxide, or with one mole of an α, α'-disubstituted p-xylene compound of the formula: where Z has the meaning given above, where A in the resulting compound of formula I corresponds to the group Z, and - if desired - replacement of the Z group by another desired anion of A. A compound with beneficial action and which is therefore preferred is 1,10-bis-[4-(octyl-amino)-1-pyridinium]decanedibromide or dichloride. This compound is obtained by reacting two moles of a compound of formula III, where R is n-octyl with one mole of a compound of formula IV, where Y is a straight-chain alkylene group with 10 carbon atoms and Z has the above meaning.

The reaction of compound III with compound IV or V is suitably carried out in an inert solvent, such as a lower alkanol, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, benzene, toluene, xylene and the like, at the temperature of the range 80-150°C for a period of 1-24 hours. Usually the reactants will be heated at 60°-100°C in acetonitrile or N,N-dimethylformamide or a mixture of these solvents or in a lower alkanol for a period of 2-20 hours.

Alternatively, the reaction can be carried out in the absence of a solvent by heating stoichiometric amounts of the reactants at temperatures of 120-150°C for from 2-5 hours.

The resulting bis-[4-(R-amino)-1-pyridinium] compounds can be isolated in the usual way, e.g. by filtration, if the product is insoluble in the reaction medium, or by diluting the reaction mixture with a non-polar solvent such as ether, benzene or hexane to thereby precipitate the product, or by evaporating the reaction medium so that the product is obtained as a residue. The resulting crude product can be purified by crystallization from a suitable solvent in the presence of an absorbent, e.g. charcoal or diatomaceous earth.

Bis-[4-(R-amino)-1-pyridinium] compound prepared as indicated above will of course contain an anion (A in formula I) corresponding to the leaving group in the disubstituted alkane or xylene (Z in formula IV and V).

However, the anion group in these compounds can be varied,

if this is desired, in the usual way, e.g. by passing a solution of a pyridinium compound in a suitable solvent such as methanol, ethanol or water, through a layer of synthetic ion exchange resin containing the desired anion. The solvent can then be evaporated, and the resulting pyridinium compound containing the desired anion can then be purified by recrystallization from a suitable solvent.

Alternatively, a pyridinium compound can be reacted with a soluble salt containing the desired anion in connection with a counter cation which combines with the anion in the pyridinium compound so that an insoluble precipitate is produced. This can then be removed, as a solution of the pyridinium compound containing the desired anion is then obtained. For example, a bis-[4-(R-amino)-1-pyridinium]alkane dihalide can be reacted with the silver salt of an organic or inorganic acid.

The precipitated silver halide is removed, whereby a solution of the pyridinium compound containing the desired organic or inorganic anion is obtained.

The above type of metathesis reactions can also be used for

to prepare insoluble pyridinium compounds. Thus, a soluble bis-[4-(R-amino)-1-pyridinium] compound can be reacted with a soluble salt containing the desired anion

which combines with the pyridinium cation, whereby the desired product is obtained as an insoluble precipitate. Such insoluble pyridinium salts can be suitable for good isolation and purification, and can be suitably processed into emulsions, creams, pastes, ointments or powders, and can also be used as depot preparations to provide a slow and delayed release of the pyridinium compound .

Thus, should the anion part of a given compound have certain undesirable properties such as solubility, stability, molecular weight, physical appearance, toxicity or the like, this compound can easily be converted into another and more suitable form. For use on skin and other tissues or in the oral cavity, one will of course use pharmaceutically acceptable anions such as fluoride, chloride, bromide, iodide, methanesulfonate and the like.

The 4-(R-amino)pyridines (formula III) which are used as starting compounds are generally known, and if they are new - they can be prepared by the methods indicated for the preparation of the known compounds.

Appropriately, said 4-(R-amino)pyridines can be prepared

by reacting 4-chloro or 4-bromopyridine or N-(4-pyridyl)-pyridinium chloride hydrochloride with an appropriately substituted amine. The reaction is usually carried out by heating the reactants in the absence of a solvent at 150-225°C for 1 1/2-3 hours. The product can be insulated in the usual way, e.g. by extraction from an alkaline aqueous medium into an organic solvent such as ether, methylene chloride or chloroform, after which the organic solvent is evaporated and the residue crystallized from a suitable solvent.

Alternatively, 4-(R-amino)pyridines obtained by catalytic hydrogenation of a mixture containing 4-aminopyridine and a carbonyl compound containing a suitable carbon content. The reaction is usually carried out at temperatures of 50-70°C in a suitable solvent, e.g. ethanol, under a hydrogen pressure of 1.5-4.5 kg/cm in the presence of a palladium hydrogenation catalyst. Usually, a hydrogenation time of 4-10 hours will be satisfactory. The use of a large excess of the carbonyl compound, e.g. 200% or greater will advantageously give a higher yield of a pure product in a reaction time of 5 hours or less. After the catalyst has been removed, the product can be isolated by evaporating the solvent and either distilling the residue or crystallising it from a suitable solvent.

The reaction between an aldehyde with a suitable carbon content

with 4-aminopyridine in the presence of formic acid at elevated temp., also gives 4-(R-amino)pyridines.

4-(R-amino)pyridines can also be prepared by acylating 4-amino-pyridine with an acyl halide of suitable carbon content, after which reducing the resulting amide. The acylation is carried out in the usual way, e.g. reacting 4-aminopyridine with an acyl halide in an inert solvent such as methylene dichloride or chloroform in the presence of an acid acceptor, e.g. triethylamine. The produced amide is then reduced with a complex metal hydride, e.g. lithium hydride in a suitable solvent such as e.g. tetrahydrofuran, ether or dioxane, and the amine product can be isolated in a conventional manner.

Disubstituted alkanes of formula IV used as starting materials are usually known, or if they are not, they can be prepared by methods known to prepare the known compounds.

α,α'-disubstituted xylenes of formula V which can also be used as starting compounds are generally known compounds,

or if not then they can be produced using known advances.

Thus, a suitable chloro- or methyl-substituted terephthalic acid or ester can be reduced to the corresponding xylene-α,α'-diol with a metal hydride such as lithium aluminum hydride in a suitable solvent such as tetrahydrofuran, ether or dioxane.

The produced xylene-a,a'-diol can then be converted into an a,a'-dihaloxylene, e.g. by reaction with hydrogen bromide, phosphorus tribromide, phosphorus oxychloride, thionyl chloride or potassium iodide or orthophosphoric acid using known methods. Alternatively, the xylene-α,α<1->diol can be converted into a sulfonate ester by a reaction with methane, ethane, benzene or p-toluenesulfonyl chloride in the presence of an acid acceptor such as e.g. pyridine, which occurs using known methods.

As described in more detail below, compounds of formula I will have in vitro antimicrobial activity against several types of microorganisms of the type that include both gram-positive and gram-negative bacteria, further against many types of fungi and Herpes virus. The compounds can thus be worked up in suitable pharmaceutical diluents to treat infections caused by bacteria, fungi or Herpes virus, e.g. in the form of ointments or creams or the like by being processed into common base substances for such preparations, e.g. alkyl polyether alcohols, cetyl alcohol, stearyl alcohol and the like, or as powders by adding common powder substances such as starch, talc or the like, or gel preparations by adding common gel substances such as glycerol and tragacanth. They can also be processed for use in aerosols or in foaming agents.

The molecular structure of the prepared compounds was established on the basis of studies of their infrared and nuclear magnetic spectra, and confirmed by a correspondence between calculated and found values for the elements present.

The following examples illustrate the invention.

Example 1

A. A mixture containing 130 g (0.67 mol) of 4-bromopyridine hydrochloride and 152 g (1.0 mol) of n-heptylamine hydrochloride was heated on an oil bath. When the bath temperature reached 180-185°C, the reaction mixture began to melt, and stirring began. At 190-195°C the melting was complete, and the liquid mixture was stirred at 210-220°C for 2.5 hours. It was then cooled to room temperature, and the resulting solid was dissolved in water, made alkaline with 35% aqueous sodium hydroxide, and the product was extracted with chloroform. The chloroform extracts were dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The resulting viscous oil was diluted with a small amount of n-hexane and cooled to give a solid which was collected by filtration and dried to give 86.6 g of 4-(heptylamino)pyridine, m.p. 4 9-51°C.

B. Alternatively, 4-(heptylamino)pyridine can be prepared as follows: A mixture containing 229 g (1.0 mol) of N-(4-pyridyl)pyridinium chloride hydrochloride and 228 g (1.5 mol) of n-heptylamine hydrochloride was heated for 2 hours in an oil bath at 215°C. The reaction mixture was cooled to 80°C, diluted with ice water, made alkaline with 35% aqueous sodium hydroxide and extracted successively with ether and chloroform. The organic extracts were combined and evaporated to dryness under reduced pressure. The resulting viscous oil was dissolved in ether, and the ether solution was washed with water. The aqueous wash was back-extracted with chloroform, and the chloroform extract was combined with the ether solution. The combined organic solutions were dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. By cooling the remaining oil to -78°C, a partial solidification was obtained.

The semi-solid was diluted with a small amount of ether and filtered. A solid was thereby obtained which was dissolved in a mixture of acetonitrile and chloroform, and the resulting solution was treated with decolorizing carbon, filtered, and the filtrate was evaporated to dryness under reduced pressure. The resulting semi-solid was diluted with a small amount of ether and cooled. A solid was thus obtained which was collected by filtration and washed with a small volume of cold ether,

and after drying, 84.6 g of 4-(heptylamino)pyridine were obtained,

m.p. 50-52°C.

C. 4-(heptylamino)pyridine was also prepared by hydrogenating a mixture containing 4-aminopyridine and heptaldehyde as described in Ex. 10B in what follows. D. A stirred hot solution containing 10.0 g (0.052 mol) 4-(heptylamino)pyridine in 40 mL acetonitrile was added dropwise to a solution containing 9.3 g (0.026 mol) 1,14-dibromotetradecane in 230 mL acetonitrile, and the mixture was then refluxed for 20 hours. The product which precipitated on cooling the reaction mixture to room temperature was collected by filtration, washed with cold acetonitrile and dried, whereby 13.9 g of 1,14-bis-[4-(heptylamino)-1-pyridinium]tetradecanedibromium was obtained, m.p. 88-90°C.

Example 2

A solution containing 5.0 g of 1,14-[4-(heptylamino)-1-pyridinium]tetradecanediobromide in 5.0 ml of methanol was added to the top of a 7.5 cm diameter column containing 500 ml synthetic anion exchange resin in the chloride form "Amberlite IRA 400", packed in methanol and then eluted with four 125 ml portions of methanol. The combined eluate was evaporated to dryness under reduced pressure, and the remaining oil was dissolved in ethanol, treated with decolorizing carbon and evaporated to dryness. The resulting solid was treated with ether containing a few drops of acetonitrile, collected by filtration and dried over phosphorus pentoxide under vacuum to give 3.94 g of 1,14-bis-[4-(heptylamino)-1-pyridinium] tetradecanedichloride, m.p. 113-116°C.

Example 3

A stirred suspension containing 11.54 g (0.06 mol) of 4-(heptyl-amino)pyridine in 75 ml of acetonitrile was refluxed until a clear and homogeneous solution was obtained. The clear solution was then added dropwise to a hot solution containing 9.84 g (0.03 mol) of 1,12-dibromodocedane in 75 ml of acetonitrile. After the addition was finished, refluxing was continued for 18 hours. After cooling to room temperature, the reaction mixture was evaporated to dryness under reduced pressure. The remaining solid was stirred in ether, collected by filtration and dried for 48 hours in vacuum at 60°C,

and 21.1 g of 1,12-bis-[4-(heptylamino)-1-pyridinium] dod' ecanidibromide were obtained, m.p. 101-103 oC.

Example 4

A. A solution containing 6.6 g of 1,12-bis-[4-(heptylamino)-1-pyridinium]dodecane dibromide in 25 ml of methanol

was added to the top of a 7.5 cm diameter column and packed with 1 liter of synthetic anion exchange resin in the chloride form "Amberlite IRA 400" in methanol and slowly eluted with 100 ml portions of methanol until 700 ml of eluate was collected. The combined eluate was evaporated to dryness under reduced pressure at 25°C. The resulting gummy substance was treated several times with a 6:1 mixture of ether and acetonitrile and then dried under vacuum to give 5.0 g of 1,12-bis-[4-(heptylamino)-1-pyridinium]dodecanedichloride, m.p. 109-112°C.

B. Alternatively, a mixture containing 76.8 g (0.4 mol) 4-(heptylamino)pyridine and 4 7.8 g (0.2 mol) 1,12-dichlorododecane can be heated for 4 hours at 125-130° C.

After slight cooling, 300 ml of acetonitrile was added, and the resulting mixture was heated on a steam bath to obtain complete dissolution and then stored in a refrigerator overnight. The precipitated product was collected by filtration, washed with cold acetonitrile and ether, and the hygroscopic product was immediately dried under vacuum, whereby 112 g of 1,12-bis-[4-(heptylamino)-1-pyridinium]dodecanedichloride, m.p. . 112-115°C.

Example 5

A. A mixture containing 100 g (0.51 mol) of 4-bromopyridine hydrochloride and 110 g (0.8 mol) of n-hexylamine hydrochloride was heated on an oil bath. When the bath temperature reached 175-180°C, the reaction mixture began to melt and stirring was begun. The temperature was then raised to 227°C and stirring continued for 3.5 hours. After cooling to room temperature, the mixture was dissolved in hot water, the resulting solution was cooled with ice, made alkaline with dilute aqueous sodium hydroxide and extracted with chloroform. The chloroform extracts were dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The residue was treated with ether and cooled. The resulting solid was collected by filtration and washed with cold ether. Evaporation of the filtrate gave another yield of solid. The solids were combined, dissolved in chloroform, treated with decolorizing carbon and filtered. The filtrate was evaporated under reduced pressure and the residue was treated with cal ether. The product thus obtained was collected by filtration, washed with cold ether and dried, thereby obtaining 63.6 g of 4-(hexylamino)-pyridine, m.p. 66-68°C. Evaporation of the filtrate gave a further 7.0 g with a m.p. at 65-67°C.

B. Alternatively, 4-(hexylamino)pyridine can be prepared as follows: A mixture containing 229 g (1 mol) of N-(4-pyridyl)pyridinium chloride hydrochloride and 207 g (1.5 mol) of n-hexylamine hydrochloride was stirred and kept warm in 1.75 hours at 175-185°C. The reaction mixture was cooled and diluted with 750 ml of ice water. The resulting solution was made alkaline with 35% aqueous sodium hydroxide and after dilution with 1 liter of water was extracted with ether and then with dichloromethane. The organic extracts were combined, dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The residue was crystallized from ether, redissolved in chloroform, and the solution treated with decolorizing carbon and filtered. The filtrate was evaporated to dryness under reduced pressure and the residue was treated with cold ether to give 71.0 g of 4-(hexylamino)pyridine, m.p. 68-70°C. C. A stirred hot solution containing 10.7 g (0.06 mol) 4-(hexylamino)pyridine in 50 ml acetonitrile was added dropwise to a solution containing 10.7 g (0.03 mol) 1,14-dibromotetradecane in 250 ml of acetonitrile, and the resulting mixture was refluxed for 22 hours. The reaction mixture was then evaporated to dryness under reduced pressure.

The remaining solids were dissolved in acetonitrile, and

the resulting solution treated with decolorizing carbon and filtered. The filtrate was evaporated to dryness under reduced pressure and the resulting oil crystallized from acetonitrile. The product was collected by filtration and dried for 48 hours at 70°C/0.1 mm Hg, whereby 13.4 g of 1,14-bis-[4-(hexylamino)1-pyridinium]tetradecanedibromide, m.p. 91-93°C.

Example 6

By using the same procedure as described in Ex. 2, but by using 5.0 g of 1,14-bis-[4-(hexylamino)-1-pyridinium]-tetradecanedibromide, 4.33 g of the corresponding dichloride was produced, m.p. 94-95°C.

Example 7

By using the same procedure as described in Ex. 5C, but by using 10.7 g (0.06 mol) 4-(hexylamino)pyridine and 9.85 g (0.03 mol) 1,12-dibromododecane, 17.6 g of 1,12- bis-[4-(hexylamino)-1-pyridinium]dodecanedibromide, m.p. 122-124°C.

Example 8

By using the same procedure as described in Ex. 2, but by using 5.0 g of 1,12-bis-[4-(hexylamino)-1-pyridinium]-dodecanedibromide, 3.69 g of the corresponding dichloride was produced, m.p. 86-88°C.

Example 9

A. A mixture containing 183.3 g (0.8 mol) of N-(4-pyridyl)pyridinium chloride hydrochloride and 162 g (0.98 mol) of n-octylamine hydrochloride was heated in an oil bath at 225-230°C (internal temperature of 188°C), and the resulting liquid was stirred at this temperature for 2.5 hours. The reaction mixture was then cooled to 70°C, diluted with 1 liter of ice and water, made alkaline with 30% aqueous sodium hydroxide and extracted with chloroform. The chloroform extracts were dried over anhydrous sodium sulfate, treated with decolorizing carbon and evaporated to dryness under vacuum. The resulting oil was cooled to -78°C. The semi-solids that formed were treated with ether, and the solid was collected by filtration, washed with cold ether and dried. The filtrate gave another yield of 10 g. The combined yields were combined, dissolved in chloroform and then treated with decolorizing carbon and filtered (repeated 3 times), after which the chloroform solution was evaporated to dryness under reduced pressure.

The resulting solid was treated with ether, cooled, collected by filtration and washed with cold ether-hexane to give 63.3 g of next colorless 4-(octylamino)-pyridine, m.p. 62-63°C.

B. Alternatively, 4-(octylamino)pyridine can be prepared as follows: A mixture containing 94 g (1 mol) of 4-amino-pyridine, 384 g (3 mol) of octaaldehyde, 7 g of 10% palladium-on-carbon hydrogenation catalyst and sufficient absolute ethanol to give a total volume of 1.2 litres, was hydrogenated for 4.5 hours at 70-90 oC under an internal hydrogen pressure of approx. 3.3 kg/cm o. After cooling, the catalyst was removed by filtration, and the filtrate was evaporated to dryness under reduced pressure. The remaining oil was crystallized on standing, and the solid product was treated with hexane, collected by filtration, washed with fresh hexane and dried at 40°C under vacuum to give 182 g of 4-(octylamino)pyridine, m.p. 70-73°C. C. A stirred hot solution containing 10.0 g (0.049 mol) 4-(octylamino)pyridine in 150 mL acetonitrile was added dropwise to a solution containing 7.4 g (0.0245 mol) 1,10-dibromodecane in 50 ml of acetonitrile, and the resulting mixture was refluxed for 18 hours. After cooling and stirring for 1 hour at room temperature, the precipitated solid was collected by filtration, washed with acetonitrile and dried for 48 hours at 85°C, and 15.6 g of 1,10-bis-[4-( octylamino)-1-pyridinium]decanedibromide, m.p. 163-164°C.

Example 10

A. By using the same procedure as described in example 2, but by using 5.0 g of 1,10-bis-[4-(octylamino)-1-pyridinium]decane dibromide, 4.31 g of the corresponding dichloride was produced , m.p. 213-214°C.

B. Alternatively, a mixture containing 61.8 g of 4-(octylamino)pyridine and 31.5 g of 1,10-dichlorodecane can be stirred and heated slowly at 120°C. The heat source was removed and the temperature of the now exothermic reaction continued to rise to 180°C.

As soon as the reaction mixture began to crystallize, 250 ml of N,N-dimethylformamide was quickly added and the resulting mixture was heated to give a clear homogeneous solution which was cooled to 0°C. The precipitated product was collected by filtration, washed with ether and dried for 24 hours under vacuum at 60°C, whereby 73 g of 1,10-bis[4-(octylamino)-1-pyridinium] decane dichloride were obtained, m.p. 215-217°C.

Example 11

By using the same procedure as described in Ex. 9C,

but by using 11.1 g (0.054 mol) of 4-(octylamino)pyridine and 7.34 g (0.027 mol) of 1,8-dibromooctane and heating the mixture for 6 hours under reflux, 15.6 g of 1,8 -bis-[4-(octyl-amino)-1-pyridinium]octane dibromide, m.p. 174-175°C.

Example 12»

By using the same procedure as described in Ex. 2, but by using 5.0 g of 1,8-bis-[4-(octylamino)-1-pyridinium]octane dibromide, 4.30 g of the corresponding dichloride was obtained, m.p. 210-211°C.

Example 13

By using the same procedure as described in Ex. 9C, but by using 11.1 g (0.054 mol) 4(octylamino)pyridine and 6.6 g (0.027 mol) 1,6-dibromohexane and heating and refluxing the mixture for 9 hours, 15.1 g 1,6-bis-[4-(octylamino)-1-pyridinium]hexanedibromide, m.p. 136-138°C.

Example 14

The same procedure was used as described in Ex. 2, but used 5.0 g of 1,6-bis-[4-(octylamino)-1-pyridinium]hexane di-bromide <p>g produced 4.23 g of the corresponding dichloride, m.p. 189-191°C.

Example 15

A stirred hot solution containing 2.06 g (0.01 mol) 4-(octylamino)pyridine in 15 ml acetonitrile was added dropwise to a solution containing 1.37 g (0.005 mol) 1,6-hexane-diol dimethanesulfonate in 10 ml acetonitrile , and the resulting mixture was refluxed for 20 hours. The reaction mixture was evaporated to dryness under reduced pressure,

and the remaining gummy material was treated with ether to give a colorless hygroscopic solid. This product was redissolved in a mixture of ethanol, benzene and acetonitrile and the resulting solution evaporated to dryness under reduced pressure. The residue was treated with ether, and the resulting white solid was quickly collected by filtration, washed with anhydrous ether, and dried for 72 hours at

28°C/0.1 mm Hg, yielding 2.65 g of 1,6-bis-[4-(octyl-amino)-1-pyridinium]hexane dimethanesulfonate as a waxy white solid.

Molecular weight calculation:

Example 16

The same procedure was used as described in Ex. 9C, but using 14.24 g (0.08 mol) 4-(hexylamino)-pyridine and 8.64 g (0.04 mol) 1,4-dibromobutane, and after treatment of the crude product with a mixture of acetonitrile and acetone , 20.45 g of 1,4-bis-[4-(hexylamino)-1-pyridinium]butane dibromide were obtained, m.p. 199-201°C.

Example 17

The same procedure was used as described in Ex. 9C, but using 10.7 g (0.06 mol) 4-(hexylamino)-pyridine and 7.32 g (0.03 mol) 1,6-dibromohexane, and after treatment of the crude product with a mixture of ether, acetonitrile , and acetone gave a total of 14.90 g of 1,6-bis-[4-(hexylamino)-1-pyridinium]hexanedibromide, m.p. 178-179°C.

Example 18

By using the same procedure as described in Ex. 9C,

but by using 10.7 g (0.06 mol) of 4-(hexylamino)-pyridine and 7.75 g (0.03 mol) of 1,7-dibromoheptane, after treating the crude product with a mixture of acetonitrile and acetone, a total of 16.4 g of 1,7-bis-[4-(hexylamino)-1-pyridinium]-heptanedibromide, m.p. 157-158°C.

Example 19

The same procedure was used as described in Ex. 9C, but used 10.7 g (0.06 mol) 4-(hexylamino)-pyridine and 8.6 g (0.03 mol) 1,9-dibromononane, and obtained a total of 17.15 g 1,9-bis- [4-(hexylamino)-1-pyridinium]-nonane dibromide, m.p. 114-115°C.

Example 2 0

The same procedure was used as described in Ex. 9C, but used 15.4 g (0.08 mol) 4-(heptylamino)pyridine and 8.64 g (0.04 mol) 1,4-dibromobutane, and obtained 23.1 g 1,4-bis-[ 4-(heptylamino)-1-pyridinium]butane dibromide, m.p. 229-230°C.

Example 21

The same procedure was used as described in Ex. 9C,

but used 10.0 g (0.052 mol) 4-(heptylamino)pyridine and 6.7 g (0.026 mol) 1,7-dibromoheptane and obtained a total of 14.05 g of 1,7-bis-[4-(heptylamino) —1—pyridinium]heptanedibromide, m.p. 14 2-143°C.

Example 22

By using the same procedure as described in Ex. 9C, but by using 11.6 g (0.06 mol) 4-(heptylamino)pyridine and 8.2 g (0.03 mol) 1,8-dibromooctane, a total of 18 was obtained after recrystallization from acetonitrile and ether, 6 g of 1,8-bis-[4-(heptyl-amino)-1-pyridinium]octane dibromide, m.p. 161-162°C.

Example 23

The same procedure was used as indicated in Ex. 2, but used 5.0 g (0.0076 mol) of 1,8-bis-[4-(heptylamino)-1-pyridinium] octandibromide and obtained 4.1 g of the corresponding dichloride, m.p. 206-208°C.

Example 24

The same procedure was used as indicated in Ex. 9C, but used 15.4 g (0.08 mol) 4-(heptylamino)pyridine and 11.44 g 1,9-dibromononane, and obtained 21.3 g of 1,9-bis-[4-(heptyl-amino) -1-pyridinium]nonane dibromide, m.p. 115-116°C.

Example 25

The same procedure was used as described in Ex. 2, but used 5.0 g. (0.0075 mol) 1,9-bis-[4-(heptylamino)-1-pyridinium]nonane dibromide, and obtained 4.2 g of the corresponding dichloride, m.p. 154-155°C.

Example 26

The same procedure was used as indicated in Ex. 9C, but used 15.4 g (0.08 mol) 4-(heptylamino)pyridine and 12.0 g (0.04 mol) 1,10-dibromodecane, and obtained 25.7 g of 1,10-bis-[4 -(heptylamino)-1-pyridinium]decanedibromide, m.p. 163-165°C.

Example 27

The same procedure was used as described in Ex. 2, but used 5.0 g (0.0073 mol) of 1,10-bis-[4-(heptylamino)-1-pyridinium]decanedibromide, and obtained 4.35 g of the corresponding dichloride, m.p. 209-210°C.

Example 28

A stirred suspension of 30 ml of a synthetic anion exchange resin in the hydroxide form "Amberlite IRA 4 00" in 150 ml of water was added dropwise with 48% aqueous hydrofluoric acid until the mixture became acidic. After stirring for a further half an hour, the suspension was poured into a column. The column was drained and the resin washed with a solution containing 15 ml of 48% aqueous hydrofluoric acid in 185 ml of distilled water. The resin was then washed with distilled water until the eluate was slightly acidic, and then successively with 20%, 40% and 50% aqueous methanol and finally with absolute methanol until the eluate was neutral. On top of this column of the ion exchange resin in the fluoride form was now added a solution containing 0.25 g (0.000365 mol) of 1,10-bis-[4-(heptylamino)-1-pyridinium]decanedibromide in 1 ml of methanol. The total forward fractions of 15 ml were collected. The first three fractions were combined and evaporated to dryness under reduced pressure. The oily residue was dissolved in a mixture of toluene and ethanol, and the resulting solution evaporated under reduced pressure to dryness. The remaining oil was redissolved in a mixture of benzene and acetone, and the solution concentrated to a small volume. The solid that separated was collected by filtration and dried for 24 hours at 24°C/0.1 mm Hg to give 0.11 g of impure 1,10-bis-[4-(heptylamino)-1- pyridinium]decandi fluoride, m.p. 85-90°C.

Example 29

A. A solid mixture containing 115 g (0.5 mol) of N-(4-pyridyl)pyridinium chloride hydrochloride and 119 g (0.66 mol) of n-nonylamine hydrochloride was heated in an oil bath to a temperature of 220°C (internal temperature 190 -194°C), and the resulting liquid stirred at this temperature for 2 hours. The reaction mixture was cooled to 80°C, diluted with

1.2 liters of ice and water, made alkaline with 35% aqueous sodium hydroxide and extracted with chloroform. The chloroform extracts were dried over anhydrous sodium sulfate, treated with decolorizing carbon, filtered and evaporated to dryness under reduced pressure. The remaining viscous oil was cooled to

-78°C and then treated with ether. The resulting solid was collected by filtration and washed with cold ether. The filtrate gave another yield of a solid. The combined solids were redissolved in chloroform, and the resulting solution was treated with decolorizing carbon and filtered. This was repeated once more and the filtrate was then evaporated to dryness under reduced pressure. The remaining semi-solid was treated with ether and cooled to give an almost colorless solid which was collected by filtration, washed with cold ether and dried. This solid was dissolved in chloroform, and the resulting solution was treated with de-

coloring carbon, filtered and evaporated to dryness under reduced pressure. The semi-solid was cooled and treated with ether to give a colorless solid which was collected by filtration, washed with cold ether and dried to give 51.7 g of 4-(nonylamino)pyridine, m.p. 59-60°C. The filtrate gave a new yield of 11.6 g, m.p. 55-57°C.

B. Alternatively, 4-(nonylamino)pyridine can be prepared as follows: A mixture containing 39.5 g (0.42 mol) 4-aminopyridine, 175 g (1.24 mol) nonylaldehyde, 5.0 g 10% palladium- on-carbon hydrogenation catalyst and sufficient absolute ethanol to give a total volume of 60 ml was heated and hydrogenated under an initial hydrogen pressure of 4.3 kg/cm until the absorption of hydrogen stopped. The reaction mixture was filtered to remove the catalyst and the filtrate evaporated to dryness under reduced pressure. The remaining oil was vacuum distilled to

remove any nonyl alcohol that may have been produced. The fraction boiling at 63-64°C/4.5 mm was collected and set aside. The residue was treated with ether and cooled to -78°C. The solid that separated was collected by filtration and washed with cold ether. This product was dissolved in chloroform, the resulting solution treated with decolorizing carbon, filtered, after which the filtrate was evaporated to dryness. The residue was treated with ether and cooled to -78°C.

The solid was collected by filtration, washed with cold ether and air-dried, after which 27.0 g of 4-(nonylamino)-pyridine were obtained, m.p. 57-59°C.

C. A stirred suspension of 11.0 g (0.05 mol) 4-(nonyl-amino)pyridine in 150 ml acetonitrile was heated until a clear homogeneous solution was obtained. To this clear solution was added dropwise a solution containing 6.8 g (0.025 mol) of 1,8-dibromooctane in 50 ml of acetonitrile, and the resulting mixture was refluxed for 19 hours, and a solid was precipitated. After cooling, the substance was filtered off, redissolved in methanol and the solution was treated with decolorizing carbon, filtered and evaporated to dryness under reduced pressure. Treatment of the remaining oil with ether containing a small amount of acetonitrite gave a colorless crystalline substance which was collected by filtration and dried to give 15.5 g of 1,8-bis-[4-(nonylamino)-1-pyridinium ]octane dibromide, m.p. 178-179°C.

Example 30

The same procedure was used as in Ex. 29C, but used 3.54 g (0.026 mol) of 4-(propylamino)pyridine and 3.90 g (0.013 mol) of 1,10-dibromodecane, and obtained 5.19 g of 1,10-bis-[4-( propyl-amino)-1-pyridinium] decanedibromide, m.p. 206-207°C.

Example 31

The same procedure was used as in Ex. 29C, but used 14.24 g (0.08 mol) 4-(hexylamino)pyridine and 9.20 g (0.04 mol) 1,5-dibromopentane and obtained after recrystallization from acetonitrile and acetone a total of 12.3 g 1 ,5-bis-[4-(hexylamino)-1-pyridinium]pentane dibromide, m.p. 155-156°C.

Example 32

The procedure from Ex. 29C, but used 10.7 g (0.06 mol) 4-(hexylamino)pyridine and 8.2 g (0.03 mol) 1,8-dibromooctane and obtained a total of 16.3 g 1,8-bit-[ 4-(hexylamino)-1-pyridinium] octandibromide, m.p. 180-181°C.

Example 33

The same procedure was used as in Ex. 29C, but used 12.5 g (0.07 mol) 4-(hexylamino)pyridine and 10.5 g (0.035 mol) 1,10-dibromodecane and obtained 16.0 g 1,10-bis-[4- (hexyl-amino)-1-pyridinium]decanedibromide, m.p. 148-149°C.

Example 34

The procedure was as described in Ex. 29C, but 13.4 g (0.076 mol) of 4-(cyclohexylamino)pyridine and 10.34 g (0.038 mol) of 1,8-dibromooctane were used, and 19.1 g of 1,8-bis-[4- (cyclohexylamino)-1-pyridinium]octane dibromide, m.p. 270-271°C.

Example 35

The procedure as stated in Ex. 29C, but used 13.4 g (0.076 mol) 4-(cyclohexylamino)pyridine and 10.8 g (0.038 mol) 1,9-dibromononane- and obtained 16.3 g 1,9-bis-[4-( cyclohexylamino)-1-pyridinium]nonanedibromide, m.p. 149-151°C.

Example 36

The procedure was as stated in Ex. 29C, but 13.4 g (0.076 mol) of 4-(cyclohexylamino)pyridine and 11.4 g (0.038 mol) were used. 1,10-dibromodecane and obtained 19.0 g of 1,10-bis-[4-(cyclohexylamino)-1-pyridinium] decanedibromide, m.p. 226-227°C.

Example 37

A. A mixture containing 298.0 g (1.33 mol) N-(4-pyridyl)pyridinium chloride hydrochloride and 322 g (2 mol) 2-ethylhexylamine hydrochloride was heated for 2 hours with stirring in an oil bath at a temperature of 215° C. The mixture was cooled to 60°C, diluted with 500 ml of water and kept cold by the addition of ice, while being made alkaline with 35% aqueous sodium hydroxide. The alkaline mixture was extracted with ether, and the ether extract was dried over anhydrous sodium sulfate and evaporated to dryness. The remaining oil was distilled under reduced pressure, and 101.0 g of 4-(2-ethylhexylamino)pyridine was obtained, b.p. 145-150°C/0.9 mm.

B. Alternatively, 4-(2-ethylhexylamino)pyridine can be prepared as follows: A stirred solution containing 800 g (8.4 mol) 4-amino-pyridine and 1500 ml triethylamine in 6.4 1 dichloromethane was added over 3 hours a solution containing 1610 g (10.0 mol) of 2-ethylhexanoyl chloride in 1.6 L of dichloromethane. During the addition, the temperature was kept at 15°C. After the addition was complete, the mixture was heated on a steam bath for 2 hours. After cooling, the reaction mixture was washed with water, dried over anhydrous sodium sulfate and treated with decolorizing carbon and filtered. Evaporation of the filtrate gave 1843 g of N-(4-pyridyl)-ethylhexanamide.

A mixture containing 100 g (2.63 mol) of lithium aluminum hydride in 2 L of tetrahydrofuran was added at a rate sufficient to maintain gentle refluxing a solution containing 570 g (2.62 mol) of N-(4-pyridyl)-2 -ethylhexanamide in 4 1 tetrahydrofuran. After the addition was finished, which took approx. 3 hours, the reaction mixture was refluxed for 7 hours. After cooling, the mixture was successively treated with 100 ml of water, 100 ml of 15% aqueous sodium hydroxide and 300 ml of water. The solids were removed by filtration, and the solvent was evaporated from the filtrate under reduced pressure. The remaining oil was combined with the product from a similar experiment, and then vacuum distilled, and 837 g of 4-(2-ethylhexylamino)pyridine were obtained, b.p. 135-160°C/0.2 mm.

C. A stirred hot solution containing 10.3 g (0.05 mol) 4-(2-ethylhexylamino)pyridine in 50 ml acetonitrile was added dropwise to a solution containing 8.2 g (0.025 mol) 1,12-dibromodecane in 170 ml of acetonitrile, and the resulting mixture was heated for 20 hours under reflux. On cooling to 0°C, a first yield of the product was obtained and this was collected by filtration. Evaporation of the filtrate and treatment of the residue with ether gave a new yield. The combined yields were dissolved in methanol, the resulting solution treated with carbon, filtered, after which the filtrate was evaporated to dryness under reduced pressure. It

the remaining oil was cooled and treated with ether to give a slightly colored solid. Recrystallization from acetonitrile and ether followed by treatment of the product with ether

followed by acetonitrile gave, after drying for 72 hours under vacuum at 60°C, a total of 14.7 g of 1,12-bis-[4-(2-ethyl-hexylamino)-1-pyridinium] dodecane dibromide as colorless granules, m.p. . 146-147°C.

Example 38

A. A mixture containing 353.5 g (1.72 mol) of 4-(2-ethylhexylamino)pyridine and 205 g (0.86 mol) of 1,12-dichlorododecane was heated at 120°C. The heat source was removed, the temperature of the now exothermic reaction continued to rise to 180-190°C. When the temperature had fallen to 135°C, 1 liter of acetonitrile was carefully added, and the mixture was refluxed until a clear solution was obtained. The warm acetonitrile solution was combined with corresponding solutions from two previous experiments, treated with decolorizing carbon and filtered. The filtrate was cooled, and the precipitated product was collected by filtration and washed with cold acetonitrile. Two recrystallizations from acetonitrile gave 970 g of 1,12-bis-[4-(2-ethylhexylamino)-1-pyridinium]dodecanedichloride, m.p. 168-171°C.

B. Alternatively, you can use the same procedure as described in Ex. 2, but one must use 3.0 g (0.004 05 mol) of 1,12-bis-[4-(2-ethylhexylamino)-1-pyridinium]-dodecanedibromide

and then produced 2.0 g of the corresponding dichloride, m.p. 172-173°C.

Example 39

The procedure was as indicated in Ex. 37C, but 10.3 g (0.05 mol) of 4-(octylamino)pyridine and 6.45 g (0.025 mol) of 1,7-dibromoheptane were used and 14.85 g of 1,7-bis-[4 -(octylamino)-1-pyridinium]heptanedibromide, m.p. 12 9-131°C.

Example 4 0

A. The procedure from Ex. 37C, but used 11.1 g (0.054 mol) 4-(octylamino)pyridine and 7.72 g (0.027 mol) 1,9-dibromononane and obtained 17.0 g 1,9-bis-[4-(octylamino) )-

1-pyridinium]nonanedibromide, m.p. 117-119°C.

B. The corresponding dichloride can be prepared as indicated in Ex. 2, and it had a m.p. at 161-162°C.

Example 41

The procedure was as in Ex. 37C, but 10.3 g (0.05 mol) of 4-(octylamino)pyridine and 8.2 g (0.025 mol) of 1,12-dibromododecane were used and 15.2 g of 1,12-bis-[4- (octylamino)-1-pyridinium] dodecane dibromide, m.p. 119-120°C.

Example 42

The procedure was as in Ex. 37C, but 5.8 g (0.028 mol) of 4-(octylamino)pyridine and 5.0 g (0.014 mol) of 1,14-dibromotetradecane were used and 9.3 g of 1,14-bis-[4-( octylamino)-1-pyridinium]tetradecanedibromide, m.p. 113-115°C.

Example 43

The procedure was as stated in Ex. 37C, but II was used, 0 g (0.05 mol) 4-(nonylamino)pyridine and 6>1 g (0.025 mol) 1,6-dibromohexane, and 15.2 g 1,6-bis-[4- (nonyl-amino)-1-pyridinium] hexanedibromide, m.p. 152-154°C.

Example 44

The procedure was as in Ex. 4, but 6.5 g (0.0095 mol) of 1,6-bis-[4-(nonylamino)-1-pyridinium]hexanedibromide were used and a total of 4.95 g of the corresponding dichloride was obtained, m.p. 194 -195°C.

Example 45

The procedure was as stated in Ex. 37C, but one used

8.8 g (0.04 mol) 4-(nonylamino)pyridine and 5.2 g (0.02 mol) 1,7-dibromoheptane and obtained 12.2 g 1,7-bis-[4-(nonyl-

amino)-1-pyridinium]heptanedibromide, m.p. 132-134°C.

Example 46

The procedure was from Ex. 37C, but 11.0 g was used

(0.05 mol) 4-(nonylamino)pyridine and 7.15 g (0.025 mol) 1,9-dibromononane and obtained 15.7 g of 1,9-bis-[4-(nonyl-amino)-1-pyridinium] nonadibromide, m.p. 121-122°C.

Example 47

The procedure was as indicated in Ex. 37C, but 11.0 g (0.05 mol) of 4-(nonylamino)pyridine and 7.5 g (0.025 mol) of 1,10-dibromodecane were used and 15.63 g of 1,10-bis-[4-( nonyl-amino)-1-pyridinium] decanedibromide, m.p. 172-173°C.

Example 48

The procedure from Ex. 37C, but used 10.12 g (0.046 mol) 4-(nonylamino)pyridine and 7.54 g (0.023 mol) 1,12-dibromododecane and obtained 16.4 g 1,12-bis-[4-(nonylamino) )-1-pyridinium]dodecanedibromide, m.p. 105-106°C.

Example 4 9

A stirred hot solution containing 12.4 g (0.06 mol) of 4-(2-ethylhexylamino)pyridine in 100 ml of acetonitrile was added dropwise to a solution containing 6.9 g (0.03 mol) of 1,5-dibromopentane in 25 ml of acetonitrile, and the resulting solution boiled for 20 hours under reflux. The reaction mixture was cooled and diluted with ether until slightly cloudy. Further cooling and stirring gave a solid precipitate which was filtered off and washed with a cold mixture of acetonitrile and ether. The solid was dissolved in ethanol, and the resulting solution treated with decolorizing carbon and filtered. Evaporation of the filtrate gave a pale yellow viscous oil which crystallized from acetonitrile.

The resulting solid was collected by filtration, washed with cold acetonitrile ether and dried for 24 hours under vacuum at 90°C to give 13.6 g of 1,5-bis-[4-(2-ethylhexyl-amino)- 1-pyridinium]pentanedibromide, m.p. 150-151°C.

Example 50

The procedure from Ex. 4 9, but used 12.4 g (0.06 mol) 4-(2-ethylhexylamino)pyridine and 7.32 g (0.03 mol) 1,6-dibromohexane, and obtained a total of 16.1 g 1,6-bis- [4-(2-ethylhexylamino)-1-pyridinium]hexane dibromide, m.p. 208-209°C.

Example 51

The procedure was as in Ex. 49, but 12.4 g (0.06 mol) of 4-(2-ethylhexylamino)pyridine and 7.75 g (0.03 mol) of 1,7-dibromoheptane were used and 17.9 g of 1,7-bis- [4-(2-ethylhexylamino)-1-pyridinium]heptanedibromide, m.p. 219-220°C.

Example 52

The procedure was as stated in Ex. 49, but 12.4 g (0.06 mol) of 4-(2-ethylhexylamino)pyridine and 8.2 g (0.03 mol) of 1,8-dibromooctane were used and 15.9 g of 1,8- bis-[4-(2-ethylhexylamino)-1-pyridinium]octanedibromide, m.p. 160-161°C.

Example 53

The procedure was as stated in Ex. 49, but 12.4 g (0.06 mol) of 4-(2-ethylhexylamino)pyridine and 8.6 g (0.03 mol) of 1,9-dibromononane were used and 15.2 g of 1,9-bis- [4-(2-ethyl-hexylamino)-1-pyridinium] nonanedibromide, m.p. 158-159°C.

Example 54

The procedure was as stated in Ex. 49, but 12.4 g (0.06 mol) of 4-(2-ethylhexylamino)pyridine and 9.0 g (0.03 mol) of 1,10-dibromodecane were used and 17.4 g of 1,10-bis- [4-(2-ethylhexylamino)-1-pyridinium]decanedibromide, m.p. 16 2-163°C.

Example 55

Procedure was as stated in Ex. 2, but 5.0 g of I, 10-bis-[4-(2-ethylhexylamino)-1-pyridinium] decanedibromide was used and 4.11 g of the corresponding dichloride was produced, m.p. 191-192°C.

Example 56

A stirred hot solution containing 12.0 g (0.06 3 mol) of 4-(heptylamino)-yridine in 100 ml of acetonitrile was added dropwise to a solution containing 7.4 g (0.032 mol) of 1,5-dibromopentane in 25 ml acetonitrile, and the resulting mixture was refluxed for 19 hours. The reaction mixture was cooled in ice, and ether was gradually added until a colorless solid was precipitated. This was collected by filtration, recrystallized from acetonitrile and ether and dried for 48 hours at 90°C/1 mm Hg to give 15.9 g of 1,5-bis-[4-(hep-tylamino)-1-pyridinium ]pentane dibromide, m.p. 153-154°C.

Example 57

The procedure from Ex. 56, but used 19.2 g (0.1 mol) of 4-(heptylamino)pyridine and 12.2 g (0.05 mol) of 1,6-dibromohexane and obtained 27.5 g of a crude product. Recrystallization of a 15 g sample from acetonitrile and ether gave II, 45 g of 1,6-bis-[4-(heptylamino)-1-pyridinium]hexanedibromide, m.p. 149-150°C.

Example 58

A. A suspension of 24.0 g of impure 1,6-bis-[4-(heptyl-amino)-1-pyridinium]hexane dibromide in 500 ml of water was made alkaline with 3N aqueous sodium hydroxide and then extracted with chloroform. The chloroform extracts were dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The remaining oil was dissolved in methanol, and the resulting solution acidified with methanesulfonic acid and evaporated to dryness under reduced pressure. The residue was redissolved in methanol, treated with decolorizing carbon, filtered and evaporated to dryness under vacuum to give an oily residue which was treated with ether and then acetonitrile to give 18.2 g of a gummy solid. This was dissolved in water, and the solution made alkaline with 35% aqueous sodium hydroxide and then extracted with chloroform. The chloroform extracts were dried under anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The resulting solid was successively treated with ether and acetonitrile, collected by filtration and dried to give 16.3 g of a light brown solid, m.p. 105-108°C. This was dissolved in 100 ml of methanol,

and the solution acidified with methanesulfonic acid. Evaporation to dryness under reduced product gave a viscous oil which was dissolved in 20 ml of methanol and treated portionwise with 150 ml of water. The resulting suspension was cooled in ice, and the solid was collected by filtration and washed with cold water. The material was then stirred in hot acetone, cooled, collected by filtration, washed with cold acetone and then dried for 48 hours at 95°C/1 mm Hg to give 10.8 g of a light brown solid, m.p. 163-165°C. This product gave a positive chloride ion test with silver nitrate, and an NMR spectrum indicated an absence of the methanesulfonate group.

B. A suspension of 14.0 g of 1,6-bis-[4-(heptylamino)-1-pyridinium]hexane dibromide in 500 ml of water was made alkaline with 35% aqueous sodium hydroxide and then extracted with chloroform. The chloroform extracts were dried over anhydrous sodium sulfate and evaporated to dryness under reduced pressure. The partially solid residue was dissolved in 1 liter of acetonitrile-benzene, and the solution was evaporated to dryness under vacuum. This procedure was repeated three times. The final residue was dissolved in 50 ml of acetonitrile, and the resulting solution was diluted with 50 ml of benzene and cooled in ice, and after filtration, 5.3 g of a faint brown substance was obtained. The filtrate gave another yield of 4.8 g; The combined yields were combined and dissolved in 50 ml of acetonitrile. Dilution with ether precipitated a solid which was filtered off and dried for 48 hours at 95°C/1 mm Hg to give 8.85 g of a light brown substance, m.p. 174-176°C. This product also gave a positive chloride ion test with silver nitrate. C. The products from parts A and B above were combined, mixed with 300 ml of water and heated until a homogeneous solution was obtained. The solution was filtered off, and the filtrate was treated with 50 ml of 12N hydrochloric acid. The resulting suspension was concentrated under reduced pressure and the residue was treated with ice. The solid product was collected by filtration,

washed with cold water and dried. The product was then dissolved in acetone, the solution was diluted with a mixture of benzene and ethanol and the whole was evaporated to dryness under vacuum. The solid residue was suspended in 100 ml of acetone and then diluted with ether and filtered, whereupon after drying for 48 hours at 105°C and 1 mm Hg and 72 hours at 115°C and 1 mm Hg, a total of 16.3 g was obtained of an impure 1,6-bis-[4-(heptylamino)-1-pyridinium]-hexane dichloride as a white solid, m.p. 176-178°C.

Example 59

The procedure from Ex. 56, but used 10.30 g (0.050 mol) 4-(2-ethylhexylamino)pyridine and 5.4 g (0.025 mol) 1,4-dibromobutane and obtained a total of 14.9 g 1,4-bis-[4- (2-ethylhexyl-amino)-1-pyridinium]butane dibromide, m.p. 245-246°C.

Example 60

A. A mixture containing 229 g (1.0 mol) of N-(4-pyridyl)-pyridinium chloride hydrochloride and 244 g (1.26 mol) of n-decylamine hydrochloride was stirred and heated for approx. 2.5 hours at 190-195°C. The reaction mixture was then cooled slowly to 40°C and diluted with 2 l of water. The resulting solution was cooled by the addition of ice and made alkaline with 200 ml of 35% aqueous sodium hydroxide. A dark solid was obtained, and this was filtered off and washed with cold water. The substance was then dissolved in 1 liter of chloroform, and the solution was treated with decolorizing carbon and filtered. The filtrate was evaporated under reduced pressure and the residue was treated with 150 ml of ether. The solid was redissolved in chloroform, and the solution was treated with decolorizing carbon and filtered. The filtrate was again treated with decolorizing carbon and filtered. The filtrate was evaporated to dryness under reduced pressure and the solid was treated with ether. Recrystallization from acetonitrile gave, after drying under vacuum, 96.1 g of 4-(decylamino)-pyridine, m.p. 71-73°C.

B. A stirred hot solution containing 12.2 g (0.052 mol) of 4-(decylamino)pyridine in 150-170 mL of acetonitrile was added dropwise to a solution containing 6.35 g (0.026 mol) of 1,6-dibromohexane in 60 mL acetonitrile, and the resulting mixture is heated for approx. 20 hours during reflux. The reaction mixture was then cooled in ice, and the precipitated solid was collected by filtration and washed with cold acetonitrile. The product obtained was dissolved in methanol, and the resulting solution was treated with decolorizing carbon and filtered. The filtrate was evaporated to dryness under reduced pressure, and the residue was treated with 50 ml of cold ether, collected by filtration and dried for 2 days over phosphorus pentoxide at 70°C and 0.1 mm Hg. This gave 14.6 g of 1,6-bis-[4-(decylamino)-1-pyridinium] hexanedibromide, m.p. 138-140°C.

Example 61

The procedure from Ex. 6OB, but used 12.2 g (0.052 mol) of 4-(decylamino)pyridine and 6.7 g (0.026 mol) of 1,7-dibromoheptane and obtained 16.0 g of 1,7-bis-[4-(decylamino) -1-pyridinium]heptanedibromide, m.p. 145-147°C.

Example 6 2

The procedure was as stated in Ex. 60B, but one used

11.7 g (0.050 mol) 4-(decylamino)pyridine and 6.8 g (0.025 mol) 1,8-dibromooctane and obtained 16.9 g 1,8-bis-[4-(decylamino)-1-pyridinium ]octanedibromide, m.p. 180-182°C.

Example 6 3

The procedure was as in Ex. 60B, but 11/7 g (0.050 mol) of 4-(decylamino)pyridine and 7.15 g (0.025 mol) of 1,9-dibromononane were used and 15.1 g of 1,9-bis-[4-(decylamino)- 1-pyridinium]nonanedibromide, m.p. 124-126°C.

Example 64

The procedure was as described in Ex. 6OB, but 11.2 g (0.048 mol) of 4-(decylamino)pyridine and 7.2 g (0.024 mol) of 1,10-dibromodecane were used and 14.6 g of 1,10-bis-[4-(decylamino)- 1-pyridinium]decanedibromide, m.p. 173-174°C.

Example 65

The procedure was as stated in Ex. 6OB, but one used

11.2 g (0.048 mol) 4-(decylamino)pyridine and 7.9 g (0.024 mol) 1,12-dibromododecane and obtained 16.5 g 1,12-bis-[4-(decylamino)-1-pyridinium ]dodecane dibromide, m.p. 102-106°C.

Example 66

A stirred hot solution containing 13.6 g (0.052 mol) of 4-(dodecylamino)pyridine in 140 ml of acetonitrile was added dropwise to a solution containing 6.34 g (0.026 mol) of 1,6-dibromohexane in 50 ml of acetonitrile, and the resulting mixture was refluxed overnight. The mixture was cooled and the solid was collected by filtration. The combined solid was dissolved in absolute ethanol, and the solution was treated with decolorizing carbon and filtered. The filtrate was evaporated to dryness under vacuum, and a white solid was obtained which was stirred in ether, filtered off and dried at 60°C/ 0.1 mm Hg, and this gave 17.63 g of 1,6-bis-[ 4-(dodecylamino)-1-pyridinium]hexane dibromide, m.p. 164-165°C.

Example 67

The procedure from Ex. 66, but used 13.6 g (0.052 mol) of 4-(dodecylamino)pyridine and 6.71 g (0.026 mol) of 1,7-dibromoheptane and obtained 18.03 g of 1,7-bis-[4-(dodecylamino) -1-pyridinium]heptanedibromide, m.p. 148-150°C.

Example 68

The procedure was as indicated in Ex. 66, but one applied

12.59 g (0.048 mol) of 4-(dodecylamino)pyridine and 6.53 g (0.024 mol) of 1,8-dibromooctane, obtaining 16.18 g of 1,8-bis-[4-(dodecyl-amino) -1-pyridinium] octandibromide, m.p. 184-185°C.

Example 69

The procedure was as stated in Ex. 66, but one used

12.59 g (0.048 mol) of 4-(dodecylamino)pyridine and 6.86 g (0.024 mol) of 1,9-dibromononane and obtained 19.35 g of 1,9-»bis-[4-(dodecyl-amino)- 1-pyridinium] nonandibromide, m.p. 134-135°C.

Example 70

The procedure was as stated in Ex. 66, but 12.59 g (0.048 mol) of 4-(dodecylamino)pyridine and 7.2 g (0.024 mol) of 1,10-dibromodecane were used and 18.08 g of 1,10-bis-[4-(dodecylamino) )-1-pyridinium]decanedibromide, m.p. 17 8-180°C.

Example 71

The procedure was as in Ex. 66, but 11.5 4 g was used

(0.044 mol) 4-(dodecylamino)pyridine and 7.22 g (0.022 mol) 1,12-dibromododecane and obtained 17.68 g 1,12-bis-[4-(dodecyl-amino)-1-pyridinium] dodecane dibromide , m.p. 75-77°C.

Example 72

A. A stirred hot solution containing 21.0 g (0.10 2 mol) of 4-(p-chlorophenylamino)pyridine in 200 ml of N,N-dimethylformamide was added dropwise to a solution containing 12.45 g (0.051 mol) 1,6-dibromohexane in 50 ml of acetonitrile, and the resulting mixture was heated for 4 hours on a steam bath. On cooling to room temperature, a solid was precipitated. The mixture was diluted with 150 ml of acetonitrile and further cooled on ice. The solid was filtered off and air-dried, and 27.2 g of 1,6-bis-[4-(p-chlorophenylamino)-1-pyridinium] hexane dibromide was obtained, m.p. 148-150°C.

B. A methanol solution of the corresponding anhydrobase was acidified with a methanesulfonic acid and evaporated to dryness under vacuum. The remaining oil was crystallized from acetone and methanol and after drying for 48 hours at 75°C/

0.1 mm Hg, a total of 25.2 g of 1,6-bis-[4-(p-chlorophenylamino)-1-pyridinium] hexanedimethanesulfonate, m.p. 108-110°C.

in

Example 73

A. A stirred hot solution containing 21.0 g (0.102 mol) 4-(p-chlorophenylamino)pyridine in 200 mL N,N-dimethylformamide was added dropwise to a solution containing 13.9 g (0.051 mol) 1.8 -dibromooctane in 50 ml of acetonitrile, and the resulting mixture was heated for a total of 1.5 hours on a steam bath. The reaction mixture was then diluted with 100 ml of acetonitrile,

and heating was continued for a further 2.5 hours, when 100 ml of acetonitrile was added. After heating again for 2 hours, the mixture was cooled, and the solid which had precipitated was filtered off, washed with a mixture of acetonitrile and ether and dried, and 30.1 g of 1,8-bis-[4-(p -chlorophenylamino)-1-pyridinium]octane dibromide, m.p. 245-247°C.

in

B. A methanol solution of the corresponding anhydrobase was acidified with methanesulfonic acid and then evaporated to dryness under vacuum. The remaining oil was dissolved in acetonitrile and the solution was treated with acetone until it became cloudy followed by clarification with a small amount of methanol and then it was cooled. The solid that precipitated was collected and recrystallized from acetonitrile and acetone to give, after drying for 36 hours at 80°C and 0.1 mm Hg, a total of 23.5 g of 1,8-bis-[4-(p- chlorophenylamino)-1-pyridinium]octandimethanesulfonate, m.p. 164-165°C.

Example 74

A. A stirred hot solution containing 21.0 g (0.102 mol) 4-(p-chlorophenylamino)pyridine in 200 mL N,N-dimethylformamide was added dropwise to a solution containing 15.3 g (0.051 mol) 1.10 -dibromodecane in 50 ml of acetonitrile, and the mixture was heated for 3.5 hours on a steam bath. The reaction mixture was then evaporated to dryness under reduced pressure, and the oil was crystallized from methanol and acetonitrile. The solid product was filtered off and washed with a cold mixture of acetonitrile and ether, yielding 28.0 g of 1,10-bis-[4-(p-chloro-phenylamino)-1-pyridinium]decanedibromide, m.p. 225-230°C.

B. A methanol solution of the corresponding anhydrobase was acidified with a methanesulfonic acid and evaporated to dryness under vacuum. The remaining oil was crystallized from acetonitrile and ether. The crude solid was dissolved in methanol, and the solution was treated with decolorizing carbon and filtered. Evaporation of the filtrate gave an oil which was suspended in a mixture of acetonitrile and acetone to give an impure solid. Recrystallization from methanol and ether gave, after drying at 48 hours at 95°C and 0.1 mm Hg, a total of 18.4 g of 1,10-bis-[4-(p-chlorophenylamino)-1-pyridinium]decandimethanesulfonate, m.p. . 202-204°C.

Example 75

A stirred hot solution containing 10.0 g (0.049 mol) of 4-(p-chlorophenylamino)pyridine in a mixture of 125 ml of N,N-dimethylformamide and 50 ml of acetonitrile was added dropwise to a solution containing 6.45 g 1,7-dibromoheptane in 25 ml of acetonitrile, and the mixture was refluxed for 19 hours. The reaction mixture was then evaporated to dryness under reduced pressure, and the remaining oil crystallized from ethanol and acetonitrile. The solid was dissolved in methanol, and the solution was treated with decolorizing carbon and filtered. The filtrate was evaporated to dryness under vacuum, and the remaining oil was recrystallized from ethanol and acetonitrile. The product was filtered off and dried for 36 hours at 105°C/0.1 mm Hg, whereby 10.4 g of 1,7-bis-[4-(p-chlorophenyl-amino)-1-pyridinium] heptane dibromide was obtained, m.p. . 202-204°C.

Example 76

The procedure from Ex. 75, but 10.0 g (0.049 mol) of 4-(p-chlorophenylamino)pyridine and 7.15 g (0.025 mol) of 1,9-dibromononane were used and 11.2 g of 1,9-bis-[4- (p-chlorophenyl-amino)-1-pyridinium] nonan dibromide, m.p. 178-179°C.

Example 77

A stirred hot solution containing 11.52 g (0.06 mol) of 4-(heptylamino)pyridine in 100 ml of acetonitrile was added in small amounts to a solution containing 7.92 g (0.03 mol) of a,a<1- >dibromo-p-xylene in 150 ml of acetonitrile. When the addition was complete, a large mass of colorless crystals separated from the solution. The reaction mixture was refluxed for 6 hours. After cooling to room temperature, the solid product was collected by filtration, washed with acetonitrile and ether, and combined with 3.1 g from a previous experiment, and it was dried for 28 hours at 100°C/0.1 mm Hg, and this gave 22.0 g of a,a<1->bis-[4-(heptylamino)-pyridinium]-p-xylene dibromide, m.p. 297-298°C.

Example 78

The procedure from Ex. 77, but 11.6 g (0.065 mol) 4-(hexylamino)pyridine and 8.7 g (0.033 mol) α,α 1-bis-[4-(hexylamino)pyridinium]-p-xylene dibromide were used, m.p. 313-315°C.

Activity against bacteria and fungi for representative examples of the compounds of formula I was determined using a modification of the autotiter method described by Goss, et al. Applied Microbiology 16 (9) 1,414-1,416 (1968) where a 1000 mcg/ml solution of the test compound was prepared.

Until the first cup in the so-called Autotray device was

0.1 ml of the sample solution was added. Activation of the auto-titer was initiated by a sequence of operations where 0.05 ml of the sample compound solution was withdrawn from the cup using a microtiter transfer loop and diluted in 0.05 ml of sterile water. Then 0.05 ml of an inoculated double-strength semi-synthetic medium (glucose) is automatically added to each cup. It all results in a final concentration ranging from 500 to 0.06 mcg/ml in double increments. The Autotray apparatus is then incubated for 18-20 hours at 37°C, after which the individual cups are examined visually for growth - which can be detected by turbidity - and the concentration of the last sample in the series which shows no growth or no turbidity, is given as the minimal inhibitory concentration (MIC) in mcg/ml. The compounds were thus tested as solutions against a number of gram-positive and gram-negative bacteria including Staphylococcus aureus, Proteus mirabilis, Escherichia coli, Klebsielle pneumoniae, Pseudomonas aeruginose, Streptococcus pyogenes and against fungi such as Aspergillus niger, Candida albicans and Trichophyton mentagrophytes.

It was further found that many of the compounds of formula I were also effective against Streptococcus mutans and Actinomyces A-vis-cosis.

Virucidal activity of representative examples against Herpes simplex type 2 virus was determined in vitro using a method equivalent to the plate inhibition test for the detection of specific inhibitors of DNA-containing virus published by E.C. Herrmann, Jr., Proe. Soc. Exp. Biol. Med. 107, 142

(1961), where 2 mg of the test compound was placed on the surface of the growth medium. The compounds corresponding to examples 3, 5C, 7, 9C, 10, 11, 13, 17, 18, 21, 22, 24, 31, 33, 49, 50, 51, 52, 53, 54, 56, 57 , 59, 75, 76, 77 and 78 were found to be active, while the compounds from Ex. 16, 39, 40 and 74B were found to be inactive.

Different data for the indicated compounds are given in the following Table A. Corresponding data for two known compounds, namely 1,8-bis(4-amino-1-pyridinium)octane bromide (reference compound I) and 1,10-bis- (4-amino-1-pyridinium) decanedibromide (reference compound II) is also included in Table A for comparative purposes. Staining concentrations for representative compounds are listed in Table C.

Antibacterial efficacy in the presence of serum was determined

for representative compounds in a standard serial tube dilution test, where pairwise comparisons of minimum inhibitory concentrations (MICs) were determined in the absence and in the presence

in the presence of heat-inactivated (30 min. at 56°C) horse serum (40%) in the sample medium. The results are expressed as fold increase in MIC (mcg/ml) against Staphylococcus aureus and Escherichia coli caused by the presence of the serum, and the results are given in Table B.

The acute oral toxicity (ALD^q) for several representative examples was determined as follows: Groups of 3 young adult male Swiss-Webster albino mice were fasted approx. 4 hours before administration and then administered the food compound once orally using a stomach tube. All mice were observed for 7 days after administration. An autopsy of the mice that were examined showed no major tissue changes, except for the group that received 1000 mg/kg of the compound from Ex. 25, where a constriction of the glandular part of the stomach was obtained in two ; of the three mice observed. The results are shown in Table C

in what follows.

Claims (2)

1. Analogous method for the preparation of bis-pyridinium-alkane and xylene compounds with therapeutic activity and with the general formula: where Y is a straight-chain alkylene group of 4-14 carbon atoms or a p-xylene group; R is an alkyl group with 3-12 carbon atoms, cyclohexyl or p-chlorophenyl; and A is an anion; m is 1 or 3; n is 1 or 2; x is 1, 2 or 3; and (m)*(2) = (n) • (x); provided that when R is p-chlorophenyl, Y is a straight-chain alkylene group of 6-14 carbon atoms, and when R is unsubstituted cyclohexyl, Y is an alkylene group of 8-14 carbon atoms, characterized by reacting 2 moles of a 4-(R -amino)pyridine compound of the formula: where R has the meaning given above, with one mole of a disubstituted alkane compound of the formula: where Y has the above meaning, and Z is chlorine, bromine, iodine, methanesulfonyloxy, ethanesulfonyloxy, benzenesulfonyloxy or p-toluenesulfonyloxide, or with one mole of an a,a'-disubstituted p-xylene compound of formula: where Z has the meaning given above, where A in the resulting compound of formula I corresponds to the group Z, and - if desired - replacement of the Z group by another desired anion of A. 2. Analogous process according to claim 1 for the production of 1,10-bis-[4-(octylamino)-1-pyridinium]decanedibromide or -dichloride, characterized in that 2 mol of a compound of formula III is reacted, where R is n- octyl with one mole of a compound of formula IV, where Y is a straight-chain alkylene group with 10 carbon atoms and Z is as stated in claim 1.