PL184026B1 - Novel method of obtaining riphamycin antibiotics - Google Patents

Abstract

. The method of obtaining spiropiperidyl derivatives rifamycin S with the given general formula, where R = CnH2n + 1, where n = 0 - 11 and m = 0 - 2, by the reaction of 3-amino-4-deoxo-4-iminorifamycin S with 4-piperidone bearing a substituent on the nitrogen atom R with the same meaning as above, characterized in that the initial 3-amino-4-deoxo-4-iminorifamycin S, or its 21,23-0- derivative, in anhydrous and solvent-free form organic, or in the form of solvates, surrenders condensation with 4-piperidone as above in the system two liquid phases that constitute the solvent organic water immiscible and aqueous solution an ammonium salt of a carboxylic acid, optionally with addition of a phase transfer catalyst at temperature from 0 ° C to the boiling point of the above-mentioned organic solvent, then, after completion of the reaction and separation of the aqueous phase into a phase organic, optionally after concentration or evaporation until dry, organic or inorganic acid is added and optionally a selective organic solvent, such as an aliphatic ketone, or an aliphatic alcohol, or ester or cyclic ether, then optionally concentrated, and after isolation, the spiropiperidyl derivative is isolated rifamycin S in the form of the addition salt of the above with the said acid of the given general formula, .....

Description

The present invention is a new process for the preparation spiropiperydylowych rifamycin S derivative of the given general formula, wherein R = C _n H 2 _n m, where n = 0 - 11 and m = 0 - 2, and HX is an acid equivalent and pharmaceutical compositions containing them.

Rifamycin antibiotics of the general formula given - are spiropiperidyl derivatives of rifamycin S, containing in the 3 and 4 positions an additional fused dihydroiimdazole ring with a spiropiperidyl residue. These compounds, especially those having an alkyl substituent on the nitrogen atom, i.e. N-alkylspyropiperidylrifamycins S, exhibit strong antibacterial activity and favorable fan properties. Particularly noteworthy is their high activity against tuberculous and non-tuberculous mycobacteria, including strains with long-term resistance. Another advantageous feature of the discussed N-alkyl4

The spiropiperidyl rifamycins S is not completely cross-resistant with rifampicin as the primary anti-tuberculosis antibiotic.

The proof of the ever-increasing importance of the discussed N-alkyl derivatives is the recent introduction of one of them with the general formula, in which R = iso-CfiHy and m = 0, to the world medicine.

There are two British patents known in the world describing this type of compounds and a method for their preparation. According to the first of them, with the number GB 1542 063, a spiropiperidyl derivative of rifamycin S with the given general formula, where R = C _n H2n + 1, where n = 1-3 and m = 0, is obtained by condensation of 3-amino- 4-deoxy-4iminorifamycin S with 4-piperidone having the R substituent on the nitrogen atom as defined above, in organic solvents such as dioxane, THF, mostly with the addition of CH3COOH, or CH3COOH alone, preferably in the presence of one of the 2 reducing systems: Zn / CH3COOH or Fe / CH3COOH, with a reaction temperature ranging from room to 70 ° C. In the above case, the synthesis of the antibiotics in question therefore takes place in a two-phase system: liquid phase - solid phase. The first is the organic solvent as given above, possibly in admixture with CH3COOH, and the second is Zn or Fe. The discussed reaction takes place in an anhydrous environment. The latter condition requires special preparation of raw materials, which increases the cost and length of the process.

According to the second of the cited patents, with the number GB 1603 127, a spiropiperidyl derivative of rifamycin S with the general formula, where R = C _n H2n + i, where n = 4 - 8 for a straight chain and n = 3 - 8 for a branched chain and m = 0, obtained by condensation of 3-amino-4-deoxo-4-iminorifamycin S with 4-piperidone having the nitrogen substituent R as defined above, in organic solvents such as THF or CH2O2, optionally in the presence of one of the following reduction systems: Zn / CH3COOH, or Zn / CH3COONHA, at a temperature ranging from 0 ° to 50 ° C. As in the previous case, the method of obtaining targets of the general formula given is carried out in a two-phase system: liquid phase - solid phase. The first is the above-mentioned single organic solvent or in admixture with CH3COOH, and the second is Zn alone or in admixture with solid ammonium acetate. According to the discussed patent, the reaction takes place in an anhydrous environment.

The similar method of isolating and purifying spiropiperidyl derivatives of rifamycin S contained in both of the above British patents is extremely complex. Ultimately the target compounds are obtained mostly from solution in an organic solvent by evaporation or by precipitation with another solvent. According to the two British patents discussed, the molar yields cited in all the examples relating to the preparation of N-alkylspyropiperidyl rifamycins S of the given general formula, where R = C _n H 2 _n + i, where n = 1 - 8 and m = 0, are in the range of 24 -50%.

In both of the discussed patents there is no information about the purity of the antibiotics obtained. However, due to the multistage nature of the process and the absence of both crystallization operations and chromatographic purification methods, most examples of both British patents discussed here are moderate. This was confirmed by the results of our experiments carried out in accordance with the examples contained in the discussed patents; in both cases, the results of our analytical tests showed that the main reaction products contain impurities, which are rifamycin derivatives with similar physicochemical properties to the antibiotics obtained, and thus clearly difficult to remove.

Additionally, the Polish patent description No. PL 168 053 is known concerning the method of preparation of spiropiperidyl derivatives of rifamycin S with the general formula, in which R = C _n H2n + 1, where n = 0 - 11 and m = 0 - 2, as a result of a multi-step reaction scheme. According to it, the starting 21,23-0-derivative of 3-aminorifamycin S is first condensed with gaseous ammonia, and the resulting 21,23-0-derivative of 3-amino-4-deoxo-4-iminorifamycin S is condensed with 4-piperidone containing the above substituent R on the nitrogen, in an anhydrous medium, which is a mixture of a liquid inert organic solvent or an excess of the above-mentioned 4-piperidone with an ammonium salt

184,026 acid or carbonic acid followed by the obtained 21,23-0-derivative

The N-alkylspiropiperidyl rifamycin S is decomposed in an acid medium and the resulting N-alkyl pyropiperidyl rifamycin S addition salt is converted by base into the target N-alkyl pyropiperidyl rifamycin S of the general formula in which R is as above and m = 0.

According to the above patent, various N-alkylspiropiperidyl rifamycins S are obtained with a molar yield of 74-83%.

All the methods for the preparation of spiropiperidyl derivatives of rifamycin S presented above are very laborious, either due to the complex, multi-stage preparation scheme (Polish patent description No. PL 168 053), or due to the complicated processing of the post-reaction mixture (British Patents No. 1542 063, 1603 127). An additional difficulty is the previously discussed need to maintain anhydrous conditions at the stage of proper condensation.

Moreover, none of the known methods provides for obtaining products with a high, minimum 98% purity, required today in the world from an increasing number of active substances used as drugs.

According to the invention, a method for the preparation of spiropiperidyl derivatives of rifamycin S with the general formula given, where R = CJUn + i, where n = 0-11 and m = 0-2, by the reaction of 3-ammo-4-deoxy-4-immo-rifamycin S with 4-piperidone, having the R substituent on the nitrogen atom as above, consists in the starting 3-amino-4-deoxo-4iminorifamycin S or its 21,23-0-derivative, in an anhydrous form and free of organic solvents or in the form of solvates, is subjected to condensation with 4-piperidone as above in a two liquid phase system, which are: an organic solvent immiscible with water and an aqueous solution of the ammonium salt of the carboxylic acid, possibly with the addition of a phase transfer catalyst, at a temperature of 0 ° C to the boiling point of the abovementioned organic solvent, and then, after completion of the reaction and separation of the aqueous phase, an organic acid is added to the organic phase, optionally after concentration or evaporation to dryness, or an inorganic and, optionally, a selective organic solvent, such as an aliphatic ketone or aliphatic alcohol, or an ester or a cyclic ether, then optionally concentrated, and after isolation, the spiropiperidyl derivative of rifamycin S is isolated as an addition salt with the above-mentioned acid of the general formula given in which R has as above m = 1 or 2, in anhydrous and free of organic solvents, or in the form of a solvate, which is optionally converted in a monophasic aqueous or aqueous-organic medium by adding an inorganic or organic base or salt to achieving the pH value of the environment in the range of 6.0 - 8.5 in the spiropiperidyl derivative of rifamycin S in the form of a base with the general formula, where R is as above and m = 0, in an anhydrous form and free of organic solvents, or in the form of a solvate, which is filtered and dried, optionally by reaction with the above-mentioned organic acid or inorganic in the above-mentioned selective solvent, such as an aliphatic ketone or an aliphatic alcohol or an aliphatic ester or a cyclic ether, or in a mixture of one of them with water or in water, is converted into a spiropiperidyl derivative of rifamycin S in the form of an addition salt with the said above with an acid of the general formula given, where R is as above, and m = 1 or 2, then separated from the post-reaction mixture in an anhydrous form, free of organic solvents, or in the form of a solvate, with a crystalline or amorphous structure.

According to the invention, the rifamycin substrate may be 3-amino-4-deoxo-4iminorifamycin S or a 21,23-0-derivative thereof, such as a 21,23-0-alkylidene derivative, or a 21,23-0-aralkylidene derivative, or , 23-O-cycloalkylidene derivative. It has turned out that not only the abovementioned anhydrous and solvent-free antibiotics, but also their solvates with water or with various organic solvents, such as 2-methoxyethanol, THF, methanol or acetonitrile, can play the role of the starting compound.

In the process according to the invention, the reaction medium for the condensation of the proper rifamycin derivative with 4-piperidone as above is a system of 2 liquid phases: liquid organic phase

184 026

- the water phase. The liquid organic phase is a water immiscible solvent such as a haloalkane, preferably methylene chloride, chloroform or ethylene chloride, or an aromatic hydrocarbon, preferably benzene, toluene, or an aryl alkyl ether such as methoxybenzene. A variant of the method is to use the above solvent with a small addition of another, for example, rifamycin substrate derived from a solvate; for example, such a solvent may be 2-methoxyethanol, THF, methanol, or acetonitrile.

The role of the water phase is played by an aqueous solution of an ammonium salt of a carboxylic acid such as, for example, formic, acetic, propionic acid. It has been found that the concentration of said salt is important for the speed of the process: it is particularly advantageous if the above aqueous solution is in the nature of a saturated solution. A variant of the method is the use of the discussed aqueous salt solution with a small addition of an organic solvent, such as 2-methoxyethanol, THF, methanol or acetonitrile.

A variant of the method according to the invention is the use of the starting 3-amino-4-deoxo-4-iminorifamycin S, or its 21.23-0-derivative, with 4-piperidone as above under the above conditions with the addition of a phase transfer catalyst (PTC) at the condensation stage. . The role of the above catalyst is played by a quaternary ammonium compound, or a phosphonium compound, or a crown ether, or a cryptand.

According to the invention, reacting 3-ammo-4-deoxy-4-iminorifamycin S or its 21,23-0-derivative, optionally in the form of solvates, with 4-piperidone as above, respectively: N-alkylspiropiperidylorifamycin S or its 21,23-0-derivative The 23-O-derivative of both compounds is in the form of a base, in solution, in the organic solvent used in the step of said condensation. Subsequently, the crude antibiotics obtained are converted by reaction with an acid into N-alkylspiropiperidyl rifamycin S addition salts. Using as a starting compound 3-amino-4-deoxy-4-iminorifamycin S or its solvate as above, following the process according to the invention, addition salts are formed directly. On the other hand, when the second of the above-mentioned substrates is used, addition salts of 21,23-0-derivative of N-alkylspyropiperidylrifamycin S are temporarily formed, which gradually, as a result of hydrolysis in an acid medium, transform into the corresponding N-alkylspyropiperidyltorifamycin S addition salts, separated from the reaction medium or processed N-alkylspiropiperidyl rifamycin S in base or addition salt form.

By carrying out the process according to the invention, it was found that, due to their basic nature, N-alkylspyropiperidyl rifamycins S form acid addition salts with organic or inorganic acids. Some of the discussed salts with organic acids such as L-tartaric, DL-tartaric, malonic, maleic, fumaric. p-nitrohernzoic, m-nitrobenzoic, or L-lactic proved to be extremely beneficial as a pharmaceutical form of the target product, as well as in the isolation and purification of parent antibiotics. It was surprisingly observed that the use of the correct acid, preferably with a pK _a <4, in a suitable solvent, mainly selective for s <oli with acid, allowed the isolation by crystallization of pure N-alkyl pyropiperidylorifamycin S addition salts, and consequently also of the parent antibiotics themselves.

According to the invention, the appropriate organic or inorganic acid used for the preparation of the N-alkyl pyropiperidyl rifamycin S addition salt is used in commercial form or in solution.

As mentioned previously, the role of the above selective solvent can be played by an organic solvent which is part of a two-phase system in which the above-mentioned condensation reaction is carried out previously. According to the invention it is a haloalkane such as methylene chloride, chloroform or ethylene chloride, or an aromatic hydrocarbon such as benzene, toluene or methoxybenzene. A variant of the method is to concentrate or practically remove the above organic solvent and use a new selective one, such as an aliphatic ketone or aliphatic alcohol, or an ester or a cyclic ether.

The spiropiperidyl derivatives of rifamycin S isolated in the above manner in the form of an acid addition salt of the above general formula, in which R is as above and m = 1 or 2, are in an anhydrous form and free of organic solvents, or in the form of a solvate . According to the invention, a combination of said salt with water and / or a selective organic solvent from which the combination is isolated is used as the solvate of the spiropiperidyl derivative of rifamycin S in the addition salt form.

The addition salts of N-alkyl pyropiperidyl rifamycins S with the acids mentioned above - as already stated - may be an end in itself. In the case where the proper target is an antibiotic in the form of a base, an exchange reaction between the above addition salt and an organic or inorganic base or other, preferably inorganic, salt is carried out in the further part of the process of the invention. The inorganic base is preferably sodium hydroxide, potassium hydroxide or ammonium hydroxide, and the organic base is preferably pyridine or an aliphatic amine. A preferred process variant is the use of an acidic or neutral ammonium carbonate or an alkali metal, particularly preferably sodium or potassium, as the inorganic salt.

The said reaction is carried out in an aqueous medium, namely in water alone or with the addition of a water-miscible organic solvent, such as an aliphatic alcohol or an aliphatic ketone, or a cyclic ether.

Under the above conditions, which are the subject of the invention, pure N-alkylspyropiperidyl rifamycins S are released in the form of a base of the general formula, in which R = Cn11'2n- +, where n = 0-11 and m = 0, which are then filtered and dried . Thus, according to the invention, spiropiperidyl derivatives of rifamycin S are obtained in the form of a base, either in an anhydrous form and free from organic solvents, or in the form of a solvate. The solvate of the spiropiperidyl derivative of rifamycin S in the base form is a combination of the said base with water and / or a selective organic solvent from which the combination is isolated.

The molar yields of the said spiropiperidyl derivatives of rifamycin S thus obtained lie in the range 74-85%.

The base antibiotics obtained by the above method can also be converted into the corresponding addition salts by the method of the invention by direct reaction of said antibiotics with acids. An inorganic or organic acid is used as the acid for the formation of said spiropiperidyl derivatives of rifamycin S in the form of addition salts of the general formula in which R = C _n H 2 "+ i, where n = 0-11 and m = 1 or 2 are used. According to the invention, the inorganic acid is preferably hydrochloric, hydrobromic, sulfuric, phosphoric or hydrogen rhodate, and the organic acid is preferably L-tartaric, DL-tartaric, malonic, maleic, fumaric, p-nitrobenzoic, m-nitrobenzoic acid. , be L-lactic. According to the invention, the spiropiperidyl derivatives of rifamycin S obtained in the above-mentioned form in the form of addition salts are isolated from the reaction mixture in an anhydrous form and free of organic solvents, or in the form of a solvate, with a crystalline or amorphous structure.

The abovementioned N-alkyl pyropiperidyl rifamycins S addition salts of the general formula in which R = C _n H 2 _n + 1, where n = 0-11 and m = 1 or 2, with the above acids can find use in medicine as standalone pharmaceutical preparations or as N-forms -alkylspiropiperidyl rifamycins S as above, which, while maintaining the biological potency of the parent antibiotics, show improved physicochemical or pharmacokinetic parameters.

The process for the preparation of spiropiperidyl derivatives of rifamycin S according to the general formula, in which R = CnRn + b where n = 0-1 and m = 0-2, which is the subject of the present invention, is superior to the previously known solutions in the following aspects. The use of a new two-phase system: liquid organic phase - an aqueous solution of an ammonium salt of a carboxylic acid as a condensation medium for 3-amino-4-deoxo-4iminorifamycin S or its 21,23-0-derivative with 4-piperidone having the R substituent on the nitrogen atom with the meaning as above, allowed to extend the possibilities of using a rifamycin substrate, the role of which in the method according to the invention may be played by

Equally suitable anhydrous antibiotics as well as their solvates with water or various organic solvents.

Moreover, according to the invention, the above reaction takes place with a minimum amount of by-products.

The use of the above-mentioned 2 liquid phase system in the process according to the invention, followed by the use of an appropriate acid in a selective solvent, ensures the synthesis of the antibiotics in question with a purity> 98%. When used as rifamycin substrate, the 21,23-O-derivative of 3-amino-4-deoxo-4-imino-rifamycin S or its solvates as above, according to a variant of the method according to the invention, increases the purity of the final products to virtually 100%.

An additional advantage of the method according to the invention over the previously known solutions is the fact that it constitutes a simple and effective solution of the process in terms of economy and environmental protection; both all organic solvents (directly or after distillation) and the aqueous solution of the ammonium salt of the carboxylic acid can be recycled and reused.

An additional aspect of the invention is a pharmaceutical composition containing known, pharmaceutically acceptable carriers and / or auxiliaries, the active ingredient containing the spiropipetidyl derivative of rifamycin S according to the invention of the general formula, in which R = C _n H 2 _n + i, where n = 0 - 11 and m = 0 or 1 or 2, with the exception of the case when R = iso-C4H9 and m = 0, or a pharmaceutical composition containing known, pharmaceutically acceptable carriers and / or auxiliaries, which contains as active ingredient prepared according to with the invention, a spiropiperidite derivative of rifamycin S of the given general formula, in which R = C _n H 2 _n + i, where n = 0 - 11 and m = 1 or 2. In addition to the said active ingredient, present in an amount of 0.1 - 99%, constituting suitable active ingredient, the composition as already mentioned preferably comprises known, pharmaceutically acceptable carriers, diluents and / or other excipients. Their quantity and quality depends primarily on the type of pharmaceutical form, as well as the properties of the antibiotic itself. In the case of the spiropipeidyl derivatives of rifamycin S according to the invention, the following forms are particularly preferred: oral tablets or capsules, rectal suppositories and infusions, and transdermal forms. In view of the good water solubility we have found of some N-alkylspyropiperidyl rifamycins S in the form of addition salts, they may also be an appropriate active ingredient in injectable preparations.

Suitable carriers and diluents in the composition according to the invention are substances typically used for this purpose in pharmaceutical practice, depending on the form of the finished drug, for example, carbohydrates, such as starch, cellulose and cellulose derivatives, lactose, talc, petroleum, vegetable oils, benzyl alcohol, polyethylene glycols, gelatin, water.

The composition according to the invention may contain auxiliary substances usually used in finished drug forms, such as preservatives, stabilizers, buffering agents, solubilizers, salts for regulating the osmotic pressure, lubricants, dyes, flavors and other auxiliaries known from pharmaceutical practice, depending on the drug form and needs.

The composition according to the invention is prepared in a manner known in the pharmaceutical practice, depending on the form of the finished drug.

The following examples illustrate the invention without limiting its scope.

Example 1 N- (n-Nonyl) spiropiperidyloryphamvcin S.

a) N- (n-nonyl) spiropiperidyl rifamycin S addition salt with maleic acid.

To a solution of 7.1 g (0.01 mol) of 3-amino-4-deoxo-4-iminorifamycin S in 80 cm ^{3 of} chloroform, 2.5 g of 1- (n-nonyl) -4-piperidone and 160 cm 3 of saturated aqueous HCOONH4 solution, then stirred at 25-30 ° C for 5 hours. After the reaction, the organic phase is separated off and the aqueous layer is extracted with 20 ml of chloroform, adding the extract obtained to the main organic phase. The resulting solution is washed successively with dilute CH3COOH solution and water (pH = 7) and then evaporated to dryness under reduced pressure. The remainder, which is crude

184 026 ο

N- (n-nonyl) spiropiperidyltorifamycin S is dissolved in 120 cm of ethanol, 1.5 g of maleic acid are added all at once to the resulting solution and the mixture is stirred at room temperature for 3 hours, then at about 5 ° C for 5 hours. Thereafter, the crystalline precipitate of N- (n-nonyl) spiropiperidylrifamycin S maleic acid addition salt is filtered, washed and dried;

the properties of the intermediate are as follows: mp = 152-158 ° C;

pH value of a 0.5% solution in 50% methanol = 4.9;

elemental analysis for the Formula C51H72N4O11 · C4H4O4 (1033.2) Calculated: 63.9% C, 7.4% H, 5.4% H;

found: 64.1% C, 7.0% H, 4.9% N.

b) N- (n-Nonyl) sprropiperidylrifamycin S.

The above-mentioned precipitate of N- (n-nonyl) spiropiperidyl rifamycin S addition salt with maleic acid is suspended in 100 cm ^{3 of} water, and then 10% NaOH solution is added dropwise with stirring until the pH of the mixture is stable at approximately

7.5. The mixture is stirred for another 2 hours, then filtered and washed with the separated precipitate. After drying, 7.6 g (yield 83%) of N- (n-nonyl) spiropiperidyl rifamycin S were obtained;

the properties of the product are as follows: = 168-175 ° C;

pH value of a 0.5% solution in 50% methanol = 7.7; elemental analysis for the Formula C51H72N4O11 (917.2) Calculated: 66.8% C, 7.9% H, 6J% N;

marked; 66.5% C, 8.0% H, 5.9% N;

HPLC purity = 98.5%.

Example II. N-Isobutylspiropiperidyl rifamycin S.

a) N-isobutylspiropiperidyl rifamycin S addition salt with L-tartaric acid.

1.85 g of 1-isobutyl-4-piperidone and 160 cm3 of a saturated aqueous solution of C2H5COONH4 are added to a solution of 7.1 g (0.01 mol) of 3-amino-4-deoxo-4-iminorifamycin S in 80 cm3 of methylene chloride and 8 cm 3 of 2-methoxyethanol, then the mixture is heated to reflux for 3 hours with stirring. After the reaction, the organic phase is separated and the aqueous layer is back-extracted with 20 cm 3 of fresh methylene chloride, adding the extract obtained to the main organic phase. The resulting solution is washed successively with dilute CH3COOH solution and water (pH = 7), then evaporated to dryness under reduced pressure. The remainder, constituting, crude. N-isobutylspiropiperidyl rifamycin S, is dissolved in 100 cm 3 of acetone, and a solution of

1.7 g of L-tartaric acid in 60 cm ^{3 of} acetone. The mixture is stirred for 6 hours at room temperature, then filtered, washed and the separated crystalline precipitate of N-isobutylspyropiperidylorphamycin S addition salt with L-tartaric acid is separated;

the properties of the intermediate are as follows: mp = 166-171 ° C;

pH value of a 0.5% solution in 50% methanol = 4.0;

elemental analysis for the Formula C46H62N4O11 · C4H6O6 (997.1) Calculated: 60.2% C, 6.9% H, 5.6% N;

found: 60.0% C, 7.2% H, 5.4% N.

b) N-Isobutylspiropiperidyl rifamycin S.

To a solution of the above-mentioned N-isobutylspiropiperidyl rifamycin S addition salt with L-tartaric acid in 120 cm 3 of water, a 50% solution of pyridine in acetone is added dropwise with stirring until a stable pH value of 6.5 is obtained. Then 2.5 g of NaCl are added and the mixture is stirred for another 2 hours, then the separated precipitate is filtered and washed. After drying, 6.4 g (74% yield) of N-isobutylspiropiperidyl rifamycin S was obtained in the form of a monosolvate with water;

the properties of the product are as follows: = 148-154 ° C;

pH value of a 0.5% solution in 50% methanol = 7.8;

184, 026 Elemental analysis for the Formula C46H 2N4O11 ₆ · H 2 O (865.0) calculated: 63.9% C, 7.5% H, 6.5% N;

found: C 64.0%, H 7.9%, N 6.4%;

HPLC purity = 99%.

Example III. N-Isobutylspiropiperidyl rifamycin S.

a) N-isobuticspyropiperidorifamycin S addition salt with hydroiodic acid.

In a two-phase system consisting of 100 cm of toluene and 160 cm of a saturated aqueous solution of C2H5COONH4, 1.85 g of 1-isbutyl-4-piperidine and 8.15 g (0.01 mol) of the 21.23-O-benzylidene derivative are dissolved. ammo-4-deoxo-4-immorph'amycin S in the form of a monosolvate with water, followed by stirring for 10 hours at room temperature. In turn, the organic layer is separated and the aqueous phase back-extracted with 25 cm ³ of toluene. 100 cm3 of water is added to the total organic solution containing the crude 21.23-O-benzylidene derivative of N-isobutylspyropiperidyl rifamycin S, followed by dropwise addition of 2N HCl solution while stirring until the constant pH value of the aqueous solution becomes 1.5. After stirring for 2 hours, the organic phase is separated off, and 0.76 g of ammonium dicride are added to the aqueous layer, which is a solution of N-isobutylspyropiperidyl rifamycin S addition salt with hydrochloric acid, and stirred for 4 hours. The precipitate is then filtered, washed and dried the precipitate of N-isobutylspiropiperidyl-famyne S addition salt with hydro-rhodanic acid;

the properties of the intermediate are as follows: mp. = 163-169 ° C;

pH value of a 0.5% solution in 50% methanol = 6.7; elemental analysis for the Formula C46H62N4O11 · HSCN (906.1) Calculated: 62.3% C, 7.0% H, 7.7% N, 3.5% S;

found: 62.7% C, 7.4% H, 7.4% N, 4% S.

b) NNzobiityidospiropiperidyloryphamycin S.

To the suspension of the above-mentioned precipitate of N-isobutylspyropiperidyl rifamycin S addition salt with rhodanic acid in 150 cm3 of the water-methanol mixture (8: 2), a 20% solution (NH4CO2) is added dropwise with stirring until the stable pH value of the suspension is about 7, 5. Subsequently, 2.5 g of NaCl are added and the mixture is stirred until it dissolves. The mixture is stirred for another 2 hours, then the precipitate is filtered and washed. After drying, 7.3 g (85% yield) of N-isobutylspyropiperidyl rifamycin are obtained. S in the form of a monosolvate with water with HPLC purity = 100%; other product properties as in example IIb.

Example IV. N-methylspiropiperidyl rifamycin S.

a) Addoc yand N-matylospbop salt Speikdylo ^I yfamyyyayyynacid msmtrobenzoonzom,

To a solution of 7.1 g (0.01 mol) of 3-amino-4-deoxo-4-iminorifamycin S in 100 cm ^{3 of} the benzene-methanol mixture (8: 2), 1.25 g of 1-methyl-4- piperidone, 0.2 g of 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo [8.8,8] hexacosane (PTC catalyst) and 160 cm ^{3 of} saturated aqueous HCOONH4 solution, and then mixing all for 3 hours at room temperature. After the reaction, the organic phase is separated off and the aqueous layer is back-extracted with 20 cm3 of fresh benzene, adding the extract obtained to the main organic phase. The resulting solution is washed with water and then evaporated to dryness under reduced pressure. The residue, crude N-methyl-pyropiperidyl rifamycin S, is dissolved in 120 cm 3 of amyl acetate, and 2.0 g of m-nitrobenzoic acid are added all at once to the resulting solution. The mixture is stirred for 6 hours at a temperature of about 5 ° C, then filtered, washed and dried the separated crystalline precipitate of N-methylpyropyridyl rifamycin S addition salt with m-nitrobenzoic acid;

the properties of the intermediate are as follows: mp. = 125-132 ° C;

pH value of a 0.5% solution in 50% methanol = 6.2;

elemental analysis for the Formula C43H56N4O11 · C7H5NO4 (972.1) Calculated: 61.8% C, 6.3% H, 7.2% N;

184,026 determined: 61.3% C, 6.6% H, 7.2% N. b) N-Methylspiropiperidyl rifamycin S.

A 10% Na2CO3 solution is added dropwise with stirring to the suspension of the above-mentioned precipitate of N-methylspiropiperidyl rifamycin S addition salt with m-nitrobenzoic acid in 150 cm ^{3 of} a water-acetone (8: 2) mixture with stirring until the stable pH value of the mixture is about 7, 0. Subsequently, 2.5 g of NaCl is added and stirred until dissolved. The mixture is stirred for another 2 hours, then filtered and washed. After drying, 6.8 g (85% yield) of N-methylspiropiperidyl rifamycin S were obtained;

the product properties are as follows: mp = 156-161 ° C;

pH value of a 0.5% solution in 50% methanol = 7.8; elemental analysis for the Formula C43H56N4011 (804.9) Calculated: 64.2% C, 7.0% H, 7.0% N;

found: C 63.8%, H 7.0%, N 6.8%;

HPLC purity = 98.5%.

Example V. N-Isobutytospiropipen'dyloryphanicin S.

a) N-isobutylspiropiperidyl rifamycin S addition salt with L-tartaric acid.

1.85 g of 1-isobutyl-4-piperidone and 160 cm3 are added to a solution of 7.9 g (0.01 mol) of 3-amino-4-deoxo-4-immorifamycin S in the form of a monosolvate with 2-methoxyethanol in 80 cm3 of methylene chloride. saturated aqueous CH3COONH4 solution was then stirred for 10 hours at room temperature. After the reaction, the organic phase is separated off and the aqueous layer is back-extracted with 20 ml of fresh methylene chloride, adding the extract obtained to the main organic phase. The resulting solution is washed successively with dilute CH3COOH and NaHCO3 solutions and water, and then evaporated to dryness under reduced pressure. Residue of crude N-izobutylospIropiperydylor / famycynę S, dissolved in 160 cm ³ of acetone, and the resulting solution is added to R &lt; 1.7 g L-tartaric acid. The mixture is stirred for 10 hours, then filtered, washed and the crystalline precipitate of N-Isobutylspyropiperidorifamycin S addition salt with L-tartaric acid as a solvate with acetone and water is separated;

the properties of the intermediate are as follows: mp = 120-127 ° C;

pH value of a 0.5% solution in 50% methanol = 4.0;

elemental analysis for the Formula C46H62N4O _n · C4H6O6 · C3H6O · 2H2O (1091.2) Calculated: 58.3% C, 7.2% H, 5.1% N;

found: 59.0% C, 7.7% H, 5.7% N;

acetone content (GC) = 4.5%.

b) N-Isobutylspiropiperidyl rifamycin S.

10% NaOH solution is added dropwise with stirring to a solution of the above-mentioned precipitate of N-Isoobutylspyropiperidyl rifamycin S addition salt with L-tartaric acid in 150 cm ^{3 of} water until a stable pH value is 7. The mixture is stirred for another 2 hours and then filtered. the separated precipitate and washed. After drying, 6.4 g (74% yield) of N-Isobutylspyropiperidyl rifamycin S was obtained in the form of a solvate with water with HPLC purity = 99%; other product properties as in example IIb.

Example VI. N-Isobutylspiropiperidyl rifamycin S.

a) Adjunct salt of N-izabutylsutyopiperidyldamyifan with n-nimobenzoic acid.

1.85 g of 1-isobutyl-4-piperidone, 0.5 g of bonzyltriethylammonium chloride are added to a solution of 7.1 g (0.01 mol) of 3-amino-4-dooxo-4-immorifamycin S in 80 cm ³ of ethylene chloride. (PTC catalyst) and. 160 cm ^{3 of a} saturated aqueous solution of HCOONII4, and then the mixture is stirred for 3 hours. in room temperature. After the reaction, the organic phase is separated off and the aqueous phase is extracted with 20 cm 3 of fresh ethylene chloride, adding the extract obtained to the main organic phase. The resulting solution was washed successively with a dilute solution of Cl 13 COOH and water (pH = 7) and then evaporated in vacuo to near dryness. Residue of crude N-Izobutylospiropiperydyloryfamycynę S, dissolved in 100 cm ^{3 of} isopropanol, to the resulting roz12

2.0 g of p-nitrobenzoic acid are added all at once. The mixture is stirred for 3 hours at a temperature of about 5 ° C, then filtered, washed and dried the separated crystalline precipitate of the N-i / ObutYlospiropiperidyl rifamycin S addition salt with p-nitrobenzoic acid;

the properties of the intermediate are as follows: mp. = 124-128 ° C;

pH value of a 0.5% solution in 50% methanol = 6.4;

elemental analysis for the Formula C46H62N4O11 · C7H5NO4 (1014.1) Calculated: C 62.8%, H 6.7%, N 6.9%;

found: C 62.7%, H 6.3%, N 6.9%

b) N-Isobutylspiropiperidyl rifamycin S.

To the suspension of the above-mentioned precipitate of N-isobutylspyropiperidyl rifamycin S addition salt with p-nitrobenzoic acid in 150 cm of water-methanol (8: 2) mixture, 10% K2CO3 solution is added dropwise with stirring until a stable pH value = 7. Then 2 is added, 5 g of NaCl and stirred for 2 hours, then the separated precipitate is filtered off and washed. After drying, 6.9 g (80% yield) of N-isobutylspiropiperidyl rifamycin S were obtained with HPLC purity = 99%; other product properties as in example II b.

Example VII. N-IsobutyiospiropipeyfryioIyjLanycyj ^ aS.

Proceeding as in Example VIa, using only a different PTC catalyst, i.e. 0.5 g of tetrabutylphosphonium chloride, the crude N-isobutylspyropiperidyl rifamycin S is obtained, which is analogously converted with L-lactic acid into the crystalline N-isobutylspyropiperipiper addition salt. the 'dyl'''f'ycin S with this acid; said intermediate is converted, in the same way as in Example VIb, into N-isobutylspiropiperidyl rifamycin S in the form of a monosolvate with water. The total product yield is 6.6 g (76%); its HPLC purity = 98.5%, other properties as in example IIb.

Example VIII. N-Methylospiropiperidylated Fryanic S.

a) N-Methylthorbidylamycin S addition salt with tartaric acid.

To a solution of 7.1 g (0.01 mol) of 3-amino-4-deoxo-4-iminorifamycin S in 100 cm3 of the mixture; methylene chloride-THF (8: 2), 160 cm3 of a saturated aqueous solution of CH3COONH4 and 1.25 g of 1-meth) -4-piperidone are added and the mixture is stirred at room temperature for 10 hours. The organic layer is then separated off and the aqueous phase is back-extracted with 20 ml of fresh methylene chloride. The combined organic phases are washed with water and then evaporated to near dryness under reduced pressure. The residue, crude N-methylspiropiperidyl rifamycin S, is dissolved in 120 ml of THF, and 3.6 g of DL-tartaric acid are added to the resulting solution. The mixture is stirred for 10 hours, then filtered, washed and dried the separated crystalline precipitate of N-methylspiropiperidyl rifamycin S addition salt with tartaric acid;

the properties of the intermediate are as follows: mp. = 143-147 ° C;

pH value of a 0.5% solution in 50% methanol = 4.0;

elemental analysis for the Formula C43H56N4O11 · C4H6O6 (955.0) Calculated: 59.1% C, 6.5% H, 5.9% N;

found: 59.4% C, 6.7% H, 5.7% N.

b) N-Methylc ^; ^ p) ^^ c ^ f) ipt ^ ridlor ^ 4amycin S.

3N NH4OH solution is added dropwise with stirring to a solution of the above precipitate of N-methylspiropiperidyl rifamycin S addition salt with tartaric acid in 150 cm3 of a water-acetone mixture (10: 1) with stirring until the pH value is 6.5. Then 2.5 g of NaCl is added and stirred until dissolved. After adjusting the pH to the above value, the mixture is stirred for 2 hours, filtered and washed with the precipitate separated out. After drying 6.0 g (75% yield) of N-methylspiropiperidyl rifamycin S with HPLC purity = 98.5%; other product properties as in example IVb.

Example IX. N- (n-Nonyl) spiropipeiydylorifamycin S.

a) N- (n-nonyl) spiropiperidylylphamycin S addition salt with fumaric acid.

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To a solution of 7.5 g (0.01 mol) of 3-amino-4-deoxo-4-S iminoryfamycyny as monosolwatu acetonitnylem with 160 cm ³ of anisole at a temperature of about 50 ° C is added

2.5 g of 1- (n-nonyl) 4-piperidone, 0.1 g of 1,4,7,10,13,16-hexaoxacyclooctadecane (PTC catalyst) and 240 cm3 of a saturated aqueous solution of C2H5COONH4, followed by stirring for 4 hours at room temperature. After the reaction, the organic phase is separated off and the aqueous layer is back-extracted with 30 cm 3 of fresh methoxybenzene, adding the extract obtained to the main organic phase. The obtained solution, containing crude N- (nnonyl] pyropiperidyl rifamycin S, is washed with water and then combined with a solution of 1.25 g of fumaric acid in 20 cm 3 of methanol. The mixture is stirred for 8 hours at room temperature, then filtered, washed and dried. crystalline precipitate of N- (n-nonyl) spiropiperidirifamycin S addition salt with fumaric acid;

the properties of the intermediate are as follows; mp = 136-145 ° C;

pH value of a 0.5% solution in 50% methanol = 3.6;

elemental analysis for the Formula C51H72N4O11 · C4H4O4 (1033.2) Calculated: 63.9% C, 7.4% H, 5.4% N;

found: 63.9% C, 6.8% H, 5.9% N.

b) N- (n-Nonyl) spiropiperidylory'famycin S.

To a suspension of the above-mentioned precipitate of N- (n-nonyl) -pyropiperidyl rifamycin S addition salt with fumaric acid in 150 cm3 of a water-THF (9: 1) mixture, a 10% solution of KHCO3 is added dropwise with stirring until a stable pH value is 7. the mixture is stirred for another 2 hours, then filtered and washed with the separated precipitate. After drying, 7.2 g (79% yield) of N- (n-nonyl) spiropiperidyl rifamycin S were obtained with HPLC purity = 98%; other product properties as in example I b.

Example X. N-isobutylspiropiperidyl rifamycin S addition salt with malonic acid.

To a solution of 0.865 g (0.001 mol) of N-S izobutylospiropiperydyloryfamycyny as monosolwatu with water in 5 cm3 of methanol is added 0.104 g of malonic acid and stirred for 3 hours, the resulting solution was added dropwise with stirring to 20 cm ³ of toluene. The mixture is stirred for another 2 hours, and then the separated amorphous precipitate is filtered, obtaining after drying 0.75 g (77% yield) of the addition salt of N-isobutylspyropiperidylrifamycin S with malonic acid with the following properties:

mp = 128-135 ° C;

pH value of a 0.5% solution in 50% methanol = 4.7;

elemental analysis for the Formula C46H62N4O11 · C3H4O4 (951.1) Calculated: 61.9% C, 7.0% H, 5.9% N;

found C 62.3%, H 7.4%, N 6.2%;

HPLC purity = 99%.

Example XI. N-methyl pyropiperidyl rifamycin S addition salt with phosphoric acid.

A solution of 0.12 g of 85% ortho-phosphoric acid in 5 cm ^{3 of} dioxane is added dropwise to a solution of 0.805 g (0.001 mol) of N-methylspyropiperidioryfamycin S in 10 cm ^{3 of} dioxane, and the mixture is stirred for 4 hours at room temperature. The separated crystalline precipitate is filtered to obtain, after drying, 0.80 g (87% yield) of the N-methylspiropiperidyl rifamycin S addition salt with ortho-phosphoric acid having the following properties:

mp = 115-118 ° C;

pH value of a 0.5% solution in 50% methanol = 5.8; elemental analysis for the Formula C43H56N 4011 · H3PO4 (902.9) Calculated: 57.2% C, 6.6% H, 6.2% N;

found: 57.7% C, 6.9% H, 6.6% N;

HPLC purity = 99.5%.

Example XII. N- (n-nonyl) spiropiperidyl rifamycin S addition salt with sulfuric acid.

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A solution of 0.917 g of N- (n-nonyl) spiropiperidyl rifamycin S in 10 cm of isopropanol at a temperature of approx. 5 ° C was combined with a solution of 0.17 cm3 of a 12N solution of sulfuric acid in 5 cm3 of isopropanol at the temperature as above The mixture was stirred for a further 3 hours at room temperature and then evaporated to near dryness. The residue was dissolved in 10 cm 3 of amyl acetate and allowed to crystallize. The separated crystalline precipitate was filtered off, obtaining after drying 0.75 g (74% yield) of the N- (n-nonyl) spiropiperidyl rifamycin S addition salt with sulfuric acid with the following properties:

mp = 185 - 190 ° C;

elemental analysis for the Formula C51H72N 4011.H2SO4 (1015.2) Calculated: 60.3% C, 7.5% H, 5.5% N;

found: 60.1% C, 7.8% H, 5.9% N;

sulfate content - 9.5%;

HPLC purity = 100%.

Example XIII. N-isobutylspiropiperidyl rifamycin S addition salt with L-tartaric acid.

For a solution of 0.865 g (0.001 mol) of N-isobutylspyropiperidyl rifamycin S in the form of a monosolvate with water, prepared according to example III. in 10 cm ^{3 of} methanol, a solution of 0.15 g of L-tartaric acid in 25 cm 3 of water is added dropwise with stirring. The whole thing is still stirred for. 1 hour, then the volatile components from the obtained solution are evaporated under reduced pressure and the residue is subjected to lyophilization. After additional drying, 1.0 g of N-isobutylspyropiperidyl rifamycin S addition salt with a purity of 99% (HPLC) is obtained; other product properties as in example IIa.

Example XIV. Capsules containing N-isobutylspiropiperidyl rifamycin S (150 mg).

A capsule mass is prepared with the following composition:

N-isobutylspiropiperidyl rifamycin S in base or addition salt form microcrystalline cellulose sodium laurilsulfate sodium glycolate starch magnesium stearate colloidal silica

15.0 g (on an anhydrous basis and free of organic solvents)

6.9 g Ug 1.0 g 0.5 g 0.1 g

The excipients indicated above are ground in a mortar until a homogeneous mixture is obtained, and then N-isobutylspyropiperidyl rifamycin S is added in portions in the form and amount indicated above, while still thoroughly grinding and mixing the entire mass.

The preparation prepared in the above manner is filled into gelatin capsules (EP II) size 0 and color L-15-3 (SCHErEr), using 0.8% technological excess of the antibiotic. 96 pieces of capsules containing N-iz ^ c ^ t ^ uiy ^ l ^ c ^ and ^ op ^ and ^^ ry ^ dylorifamycin S (150 mg) are obtained.

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H ₃ CC00 h ₃ co

. m / ΗΣ /

Pattern

Publishing Department of the Polish Patent Office. Circulation: 60 copies. Price: PLN 4.00.

Claims (17)

Patent claims 1. The method of obtaining spiropiperidyl derivatives of rifamycin S of the given general formula, where R = C _n H2 _n + i, where n = 0 -11 and m = 0 - 2, by the reaction of 3-amino-4-deoxo-4-iminorifamycin S with 4-piperidone having the R substituent on the nitrogen atom as defined above, characterized in that the starting 3-amino-4-deoxo-4-iminorifamycin S or its 21,23-0-derivative, in an anhydrous form and free from organic solvents or in the form of solvates, is subjected to condensation with 4-piperidone as above in a two liquid phase system, which are: an organic solvent immiscible with water and an aqueous solution of the ammonium salt of the carboxylic acid, possibly with the addition of a phase transfer catalyst, at a temperature of 0 ° C to the boiling point of the above-mentioned organic solvent, and then, after completion of the reaction and separation of the aqueous phase, an organic or inorganic acid is added to the organic phase, optionally after concentration or evaporation to dryness and optionally a selective organic solvent, such as an aliphatic ketone or an aliphatic alcohol or an ester or a cyclic ether, then optionally concentrated, and after isolation, the spiropiperidyl derivative of rifamycin S is isolated as an addition salt with the above-mentioned acid of the general formula given wherein R is as above and m = 1 or 2, in anhydrous form and free from organic solvents, or in the form of a solvate, which is optionally converted in a monophasic aqueous or aqueous-organic medium by adding an inorganic or organic base or salt, to achieve the pH value of the environment in the range of 6.0 - 8.5, w spiropiperidyl derivative of rifamycin S in the form of a base with the general formula, where R is as above and m = 0, in an anhydrous form and free of organic solvents, or in the form of solvate, which is filtered and dried, optionally by reaction with the above-mentioned organic acid m or inorganic in the above-mentioned selective solvent, such as an aliphatic ketone or an aliphatic alcohol, or an aliphatic ester or a cyclic ether, or in a mixture of one of them with water, or in water, is converted into the spiropiperidyl derivative of rifamycin S in the form of an addition salt with with the above-mentioned acid of the general formula, where R is as above, and m = 1 or 2, then separated from the reaction mixture, either in an anhydrous form and free of organic solvents, or in the form of a solvate, with a crystalline or amorphous structure. 2. The method according to p. A process according to claim 1, characterized in that the 21,23-0-derivative of 3-amino-4-deoxy-4-iminorifamycin S is its 21,23-0-alkylidene derivative, or the 21,23-0aralkyidine derivative or 21,23-0 -cycloalkylidene derivative. 3. The method according to p. The process of claim 1, wherein the solvate of the 3-amino-4-deoxy-4iminorifamycin S or its 21,23-0-derivative is a combination of the said compounds with water or an organic solvent such as 2-methoxyethanol or THF or acetonitrile. 4. The method according to p. The process of claim 1, wherein the water-immiscible organic solvent is a haloalkane such as methylene chloride, chloroform, or ethylene chloride, or an aromatic hydrocarbon such as benzene or toluene, or an aryl alkyl ether such as methoxybenzene, or a mixture of one of them with another inert organic solvent, such as 2-methoxyethanol or THF, or methanol or acetonitrile. 5. The method according to p. A process as claimed in claim 1, characterized in that an aqueous solution of ammonium formate, or ammonium acetate or ammonium propionate, optionally with addition of a water-miscible solvent, is used as the aqueous solution of the ammonium salt of the acid. organic, such as 2-methoxyethanol or THF or acetonitrile or methanol. 184 026 6. The method according to p. A process as claimed in claim 1, characterized in that the aqueous ammonium salt of the carboxylic acid is preferably used in the form of a saturated solution. 7. The method according to p. The process of claim 1, wherein the phase transfer catalyst is a quaternary ammonium compound, or a phosphonium compound, or a crown ether, or a cryptand. 8. The method according to p. The process of claim 1, wherein the spiropiperidyl rifamycin S addition salt solvate is a combination of said salt with water and / or a selective organic solvent from which the combination is isolated. 9. The method according to p. The process of claim 1, wherein the inorganic base is preferably sodium hydroxide or potassium hydroxide or ammonium hydroxide, and the organic base is preferably pyridine or an aliphatic amine. 10. The method according to p. A process as claimed in claim 1, characterized in that the inorganic salt is preferably acid or neutral ammonium or alkali metal, particularly preferably sodium or potassium. 11. The method according to p. The process of claim 1, wherein the solvate of the spiropiperidyl derivative of rifamycin S in the base form is a combination of said base with water and / or a selective organic solvent from which the combination is isolated. 12. The method according to p. 1, characterized in that the acid to form spiropiperydylowych derivatives of rifamycin S in the form of acid addition salts of the above general formula wherein R = C _n H2nn, where n = 0 - 11 and m = 1 or 2 are used inorganic or organic acid. 13. The method according to p. A process as claimed in claim 1, characterized in that the inorganic acid is preferably hydrochloric, hydrobromic, sulfuric, phosphoric or hydro rhodate acid, and the organic acid is preferably L-tartaric, DL-tartaric, malonic, maleic, fumaric, p-nitrobenzoic acid, -nitrobenzoic or L-lactic. 14. Pharmaceutical composition containing known, acceptable pharmaceutical carriers and / or auxiliaries, characterized in that the active ingredient is a spiropiperidyl derivative of rifamycin S of the general formula given, in which R = C _n H 2 _n + 1, where n 0 -11 and m = 0 or 1 or 2, except when R = iso-C? Th and m = 0. 15. The pharmaceutical composition of Claim 14, containing from 0.1 to 99% of active ingredient. 16. A pharmaceutical composition containing known, acceptable pharmaceutical carriers and / or auxiliaries, characterized in that the active ingredient is a spiropiperidyl derivative of rifamycin S of the general formula given, in which R = C _n H 2 _n + 1, where n 0 -11 and m = 1 or 2. 17. A pharmaceutical composition according to claim 1 16, containing from 0.1 to 99% of active ingredient.