DE2122208A1 - Diamidino-benzimidazole derivs - with fungistatic activity - Google Patents

Abstract

Title derivs. of formula (I):- (where n is 2, 3 or 4) ae active against pathogenic fungi, systemic mycoses, and dermatophytes. They are prepd. by treating corresponding dicyano-benzimidazole derivs. with dry hydrogen halide in an alcohol Alk-OH (where Alk is 1-8C aliphatic hydrocarbyl opt. contng. 1 or more O-atoms) and treating the resulting bis-(imino ester) with dry NH3 in a 1-3C alcohol.

Description

Fungistatically active diamides and processes for their production It is known that some aromatic diamidines are effective against pathogenic fungi such as skin fungi, Fungi or blastomycetes and also against systemic mycoses, such as she z. B.

caused by Candida albicans are effective; it deals are 2-hydroxy-stilbamidine, known from US Pat. No. 2,510,047 1,5-bis (4-amidino-phenoxy) pentane (pentamidine), known from US Pat. No. 2,410,796, and about 4,4'-diamidino-diazoaminobenzene, known from I) BP 895.901.

Diamidines of formula 1 have now been found, where n ei denotes an integer from the series 2, 3, 4 which are surprisingly better than the known compounds against pathogenic fungi and systemic mycoses.

The invention also relates to a process for the preparation of a compound of the formula (I), which is characterized in that a) a dinitrile of the formula II where n is an integer from the series 2, 3, 4, under the action of dry hydrogen halide with an alkanol of the formula Alk-OH, in which Alk is an aliphatic or cycloaliphatic hydrocarbon radical with 1 - 8 carbon atom tar in turn may contain one or more oxygen atoms, in a diimino ether of the formula III in which n is an integer from the series 2, 3, 4, and b) converts the dilmino ether thus obtained in an alkanol with 1-3 carbon atoms with dry ammonia to a diamidine of the formula I.

The following dinitriles are used as starting materials of the formula II Consideration: 2- (4- [2- (4-Cyano-phenoxy) -ethoxy] -phenyl) -6-cyano-benzimidazole, 2- {4- [3- (4-Oyano-phenoxy) -propoxy] -phynyl } -6-cyano-benzimldazole and 2- {4- [4- (4-cyano phenoxy) butoxy] phenyl} -6-cyaNo-benzimidazole.

The dinitrile used as the starting material is used with. t one inert solvent diluted. Open-chain solvents are primarily used as solvents Ether which s diethyl ether, diisopropyl ether or dibutyl ether, cyclic ethers such as Dioxane or tetrahydrophorane or chlorinated hydrocarbons such as methylene chloride, ethylene chloride, Choroform or carbon tetrachloride into consideration. This mixture is in the orsten Reactive onsstep a) with; pissed off with an alcohol with 1 - 8 carbon atoms. the seinerscits May contain certain or more oxygenated breaths. For this come rooted lipatic ones cabbage with 1-4 carbon atoms, such as methanol, ethanol, propanol or butanols or etherified alcohols such as methoxyethanol, ethoxyethanol or Clycolmonomethyläther into consideration.

The cyclic alcohols used are preferably those with 6 carbon atoms, especially cyclohexanol. Instead of the inert solvent, it can also be used accordingly more alkanol, e.g. 13th

Glycol monomethyl ether, can be used for the reaction.

To carry out the reaction step a), the mixture is washed with dry Hydrogen halide, preferably saturated with hydrogen chloride. The reaction temperature is between -20 and + 20 ° C, preferably between 0 and + 5 ° C. After standing for a long time the dihydrochloride of the diimino ether of the formula III precipitates. It is often useful the deposition by adding an inert solvent, e.g. B.

Complete diethyl ether. The dihydrochloride of diimino ether is filtered off and dried.

In the second reaction step b) the dihydrochloride of the diiminoether is used of the formula III in an anhydrous alkanol with 1-3 carbon atoms, preferably in Methyl alcohol or ethyl alcohol at temperatures between OOC and the boiling point of the alkanol used saturated with dry ammonia gas.

After cooling and, if necessary, concentration of the reaction mixture falls the diamidine dihydrochloxide of the formula I and is obtained by filtering and drying isolated.

The dinitrile compounds of the formula used as starting materials II can be prepared according to the Williamson ether synthesis, for example according to J.J. Randall et al., Journal of Organic Chemistry 27, 4098 (1962) or in U.S. Patent 3,032,594.

6-Cyano-2- (4-hydroxyphenyl) -benzimidazole and # - (4-cyano-phonoxy) -alkyl bromides are used in dimethylformamide in the presence of potassium carbonate at reflux temperature and the reaction product is separated by dilution after the niche has cooled down water off.

The new diamidines of the formula I are characterized by pronounced Effect against infections caused by pathogenic fungi. try showed a good fungistatic effectiveness against important representatives of the Genera Allescheria; Aspergillus; Blastomyces; Botrytis; Candida; Cryptococcus ; Cladosporium; Histoplasm; Hormodendrum; Leptospaeria; Nadurella; Penicillium; Phialophora; Pyrenochaeta; Sporotrichum and Torula.

The new diamidines according to the invention also act against dermatophytes of the genera Trichophyton, Microsporum and Epidermophyton. Against different genres a fungicidal effect was also found.

The diamidines according to the invention are used for therapeutic purposes by adding an equivalent or excess amount of a physiological compatible acid converted into the corresponding acid addition salts. In addition For example, hydrochloric acid or acetic acid, in particular aceturic acid, lactic acid, are suitable or isethionic acid.

The acid addition salts of the diamidines of the invention are useful in aqueous solutions, preferably in those with a concentration of 2-10 Total% of the diamidine salt, intramuscularly, optionally also intravenously or subcutaneously, injected.

As examples of the effects of the new diamidines according to the invention the following experiments are intended to serve: Effect example 1 The effectiveness of the new Diamidine compounds in vitro was used against various pathogens causing systemic mycoses examined.

For Candida albicans, Sabouraudts was used as the nutrient medium for the tests liquid medium (modified) is used, for the remaining germs Oxoid-Dextrose-Solution2) (Die The composition of the nutrient media is listed after Table 1.) The investigation the new diamidines in the form of their hydrochlorides were carried out in tube dilution tests with a consecutive dilution factor of 2. The tubes were kept at 280C for 10 days incubated. For the inoculation of Candida and Oryptococcus, 1,104 cells / ml used.

The preculture took place on malt extract-peptone-dextrose-agai³) (slant agar0 for 7 days at 28 ° C. The inoculation of Histoplasma, Blastomyces and Sporotrichum was carried out by transferring one culture particle each about 1 mm in diameter in each test tube. The particles were from week-long surface cultures of the Germs removed on malt extract-peptone-dextrose agar.

As ncue active ingredients according to the invention, 2- {4- [2- (4-amidino-phenoxy) g-phenyl-Ó-amidino-benzimidazole hydrochloride, referred to as diamidine 1, and 2 {4- [3- (4-Amidino-phenoxy) -propoxy] -phenyl} -6 amidino-benzimdiazole, referred to as diamidine 2, checked.

The substances according to the invention were compared with 2-hydroxy-stilbamidine isethionate (May & Baker Ltd., Dagenham, England), referred to as Comp. A; Pentamidine isethionate (Moy & Baker), designated as Comp. B, and 4,4-diamidino-diazoaminobenzene hydrochloride (BerenilW, Farbwerke Hoechst AG), referred to as cf. C.

In Table 1 below are the fungietatic concentrations - of the new diamidines in migrograms per milliliter of medium against the - different ones Pathogen listed.

Table 1 shows that the fungistatic concentrations of the new diamidines 1 and 2 are several to many times lower and thus more favorable than those of the comparative substances. TABLE 1 Comparison of the inhibitory effectiveness of the new diamidines with known compounds Fungistatic concentration of the active ingredients in KEIM Medium micrograms per milliliter (= ppm) DIAMIDIN 1 DIAMIDIN 2 cf. A cf. B cf. C tribe Candida albicans 504 Sab. 1) 4 0.5 31 31 31 - "- St 1 -" - 4 4 62 62 125 - "- 531 -" - 2 2 8 16 8 - "- FO -" - 2 - 4 4 16 16 16 - "- H 12 -" - 2 16 16 62 62 - "- You -" - 1 - 2 8 31 31 16 tribe Cryptococc. neoformans CBS 132 Oxoid 2) 8 2 31 16 62 Histoplasma capsulatum A 721-S - "- 2 - 4 2 - 4 8 - 16 62-125 8 Blastomyces dermatitidis 9 - S - "- 4 - 8 2 - 4 31 62 31-62 Sporotrichum Schenckii Bas.-S - "- 0.5 0.5 16 - 31 2 8 Footnote) to experiment t Sabouraudts liquid medium (modif.): Neopeptome (Difco) 10 g dextrose 20 g distilled water to 1000 ml additive n / 1 NaOH up to pH 6.5 Footnote²) to experiments 1 and 2 Oxoid dextrose solution: Lab Lemko meat extract, powdered [Oxoid L 29] ** 8 g peptone L 34 (Oxoid) ** 10 g dextrose 10 g Na Cl 3 g distilled water to 1000 ml + 10% acetic acid up to pll 6.5 footnote³) for experiments 1 and 2 malt extract Popton dextroso agar: Floischpopton (Merck 7214) *** 10 g malt extract "Malzextra" *** 20 g dextrose 10 g Bacto agar (Difco) 18 g distilled water to 1000 ml + n / 1 NaOH up to pH 6.5 Footnote t to experiment 2 Altromin "M", widely used standard pellet feed for mice, Altrogge, Lage / Lippe, Germany * Difco Laboratories, Detroit, Michigan (USA) ** Cxoid Ltd., London SE 1 (England) *** EE Merck AG, Darmstadt (BRD) Fa. Schöpp & Böhringer GmbH, Freudenstadt in the Black Forest (FRG) The new diamidines according to the invention were also tested for their action against Candida mycosis in mice in comparison with the aforementioned known compounds.

The candida mycosis serves, as is common practice, as a model infection for systemic fungal infections.

In the experiment, albino mice (strain NMRI, male) weighing 12-19 g intravenously with 5 million individual cells of Candida albicans, strain F0 (consistently virulent laboratory strain), infected. For inoculation was the pathogen for 7 days at 28 ° C on malt extract-peptone-dextrose agar (agar slant) bred. 0.3 ml of germ suspension in physiological saline solution was administered to each animal. Each group of animals consisted of 10 animals, and they were fed with Altromin M and tap water ad libitum. The infection generally proceeds untreated fatal within 2 - 6 days. The main organs of infection are the heart and kidneys and brain. The most important criterion for the effectiveness of a preparation is Extension of survival time compared to controls.

Table 2 below shows the survival times of mice four times subcutaneous administration of diamidine 1 according to the invention and of the known comparison substances cf. A, 13 and G.

As Table 2 shows, the survival times are that with the new one Diamidine 1 according to the invention treated animals significantly over the survival times, obtained with the comparison substances.

The new diamidine is thus significantly more effective than the known substances.

TABLE 2: Efficacy of the compounds against mycosis candida in the mouse TREATMENT RESULT Active substance application Survival rate Mean survival (in brackets: lifespan of 10 animals each (days) Solvent) single dose time in 8, 15 and at the end of the experiment (mg / kg) subcutaneously hours 22 days after that after 22 days before (-) or infection after (+) infection 8 days 15 days 22 days all: +) Diamidine 1 3.125 - 1 + 6 + 24 5 3 2> 10.3 (distilled water) 6.25 + 30 hours 9 5 3> 16.0 12.5 8 5 4> 15.0 Diamidine 1 3.125 9 2 0 11.2 (0.4% 6.25 see above 7 6 5> 14.4 Tylose mucus) 12.5 10 10 5> 20.6 See A 10.0 0 0 0 3.3 (distilled water) 20.0 see above 0 0 0 3.0 40.0 7 0 0 5.9 See B 7.5 2 0 0 4.9 (distilled water) 15.0 see above 3 0 0 5.4 30.0 2 0 0 5.4 See C 5.0 0 0 0 3.9 (distilled water) 10.0 see above 5 0 0 7.6 20.0 3 1 0 9.1 Physiological Saline solution 0.5 ml see above 0 0 0 3.9 @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Production Example 1 1115 g 2- {4- [2- (4-Cyano-phenoxy) -ethoxy] -phenyl] -6-cyanobenzimidazole are saturated with dry hydrogen chloride in 2.2 l of glycol monomethyl ether while stirring, the temperature being kept below 20 ° C. by cooling in the ice. The reaction mixture initially forms a suspension and in the course of the reaction passes temporarily into a solution from which the dihydrochloride of the diimino ether in question separates out after standing for a while. To. If left overnight in the refrigerator, the crystals are filtered off and washed with absolute ether.

The dihydrochloride of the diimino ether isolated in this way is absolute in 2 liters Entered alcohol, which was previously saturated by the introduction of dry ammonia became. A stream of ammonia is then passed through the for a further three hours Simmering heated mixture passed. After standing overnight the solvent becomes evaporated, the residue dissolved in 2.8 1 hot 2N acetic acid and the solution under Filtered addition of charcoal.

Then from the solution by adding 300 ml.

conc. Hydrochloric acid precipitated the dihydrochloride of diamidine.

After standing overnight, filtered off, with 2N hydrochloric acid and finally washed with acetone and dried on the steam bath. 99 g of 2- {4- [2- (4-amidino-phenoxy) -ethoxy] -phenyl} -6-amidino-benzimidazole are obtained of melting point 217 ° C (with sintering).

preparation example 2: 21.5 g of 2 - {- 4 [3- (4-cyano-phyenoxy) -propoxy] -phenyl} -6-cyanobenzimidazole are in 300 ml of glycol monomethyl ether while stirring with dry hydrogen chloride saturated, the temperature being kept below 200C by ice cooling. After three days of standing, the dihydrochloride of the diiminoether is added by adding Ether precipitated and as described in preparation example 1 by ammonia in Alcohol converted into the Dilrydrochlorid des Diami.dill.

23.8 g of 2 - (- 4- [3- (4-amidino-phenoxy) -propoxy] -phenyl -6-amidino-benzimdaol are obtained with a melting point of 195 C (with sintering).

Preparation Example 3 30 g of 2 - {- 4 [4- (4-cyano-phenoxy) -hutoxy] -phenyl} -6-cyanobenzimidazole are in 600 ml of methyl glycol analogous to preparation example 1 with hydrogen chloride converted into the dihydrochloride of the diimino ether in question and then reacted with ammonia in alcohol to the dihydrochloride of diamidine.

35 g of 2- {4- [4- (amidino-phenoxy) -butoxy] -phenyl} -6-amidino-benzimidazole are obtained, that sinters at 230 ° C and decomposes at 287 ° C.

Claims (10)

P a t e n t a n s p r ü c h e 1 a diamidine of formula 1; where n is an integer in the series 2 »t 3, 4. 2) 2- {4- [2- (4-amidino-phenoxy) -ethoxy] -phenyl} -6-maidinobenzimidazole. 3) 2- {4- [3-94-amidino-phenoxy) -propoxy] -phenyl} -6-amidinobenzimidazole. 4) 2- {4- [4- (4-Amidino-phenoxy) -butoxy] -phenyl} -6-amidinobenzimidazole. 5Y Process for the preparation of a diamidine of the formula I. characterized in that a) a dinitrile of the general formula II where n is an integer in the series 2, 3, 4, under the action of dry hydrogen halide with an alkanol of the formula AlkOH, in which Alk is an aliphatic or cycloaliphatic hydrocarbon radical with 1 - 8 carbon atoms, which in turn can contain one or more oxygen atoms, into a diimino ether of the formula III where n is an integer from the series 2, 3, 4, and b) converts the diimino ether thus obtained with an alcohol having 1-3 carbon atoms with dry ammonia to give a diamidine of the formula I. 6) Method according to claim 5, characterized in that one is im Reaction step a) used as hydrogen halide hydrogen chloride. 7) Method according to claim 5, characterized in that one is im Reaction step a) the aliphatic alcohol is one with 1-4 carbon atoms or used as cyclic alcohol cyclohexanol. 8) Method according to claim 5, characterized in that the Reaction step a) in an inert solvent from the series of open-chain Ether or cyclic ether or the chlorinated hydrocarbons 9) Procedure according to claim 5, characterized in that reaction step b) is carried out in methyl alcohol or ethyl alcohol. 10) means for combating pathogenic fungi, characterized in that that there is an addition salt of a diamidine as an active ingredient according to claims 1 to 4 with a physiologically acceptable acid, mixed with a pharmaceutical usual diluent or carrier.