HK1023575B - 11-acetyl-12, 13-dioxabicyclo (8.2.1)-tridecenone derivates, processes for the preparation thereof and medicaments containing these compounds - Google Patents

Description

11-acetyl-12, 13-dioxabicyclo [8.2.1] tridecenone-derivative, process for producing the same and pharmaceutical containing the same

The present invention relates to novel, N-substituted (2R, 3S, 4S, 5R, 6R, 10R, 11R) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl- α -L-ribohexopyranosyl)) -oxy ] -5- [3, 4, 6-trideoxy-3-amino- β -D-xylopyranosyl (xylohexohexopyranosyl)) -oxy ] -2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1] tridec-8-en-1-one-compounds and acid addition salts thereof, as well as pharmaceutical preparations containing these compounds and a process for preparing these compounds. The compounds of the present invention are ring closed N-demethyl-N-isopropyl-derivatives of erythromycin A having a modified side chain.

It is known that the antibiotic erythromycin a, in addition to its antibacterial action, has gastrointestinal side effects which are undesirable for the antibiotic and, in addition, markedly exacerbate the gastrointestinal contractile action with concomitant gastrointestinal spasms, nausea, vomiting and diarrhea.

There have been many attempts to modify erythromycin A to obtain derivatives thereof which are virtually non-antibacterial, but which still retain the effect of affecting gastrointestinal motility. Ring-closed N-demethyl-N-isopropyl-erythromycin-a-derivatives having motilin-potentiating properties for the gastrointestinal tract are known from european patent No. 0550895.

Furthermore, similar, but nevertheless antibiotic, ring-closed erythromycin derivatives are known from European patent application EP-A382472.

The object of the present invention was to develop new orally active, ring-closed erythromycin A derivatives which have no antibiotic action but nevertheless have properties which advantageously influence the gastrointestinal motility in an improved manner of action.

It has now been found that new N-demethyl-N-isopropyl-derivatives of ring-closed erythromycin A, the side chain of which is oxidatively modified in the 11-position of the cyclic basic skeleton, have no antibacterial action, but nevertheless have selective motilin-potentiating properties, are capable of stimulating gastrointestinal motility and have an enhancing effect on lower esophageal sphincter tone and gastric tone in an advantageous manner.

Based on its mode of action, the substances according to the invention are suitable for the treatment of gastrointestinal motility disorders and have good tolerability and good oral action.

The invention therefore relates to novel (2R, 3S, 4S, 5R, 6R, 10R, 11R) -2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1] tridec-8-en-1-one compounds of the general formula I and stable, physiologically tolerated acid addition salts thereof

Wherein

R¹Is hydrogen or methyl

R²Is hydrogen or lower alkanoyl.

If the substituent in the compounds of the formula I is or contains a lower alkyl group, this alkyl group may be branched or unbranched and contain from 1 to 4 carbon atoms.

Particularly advantageous are compounds of the formula I in which R is¹Is methyl.

R²Hydrogen is preferred. If R is²Lower alkanoyl is preferred, acetyl.

The chemical structural formulas of the compound of the formula I and the intermediate compounds of the formula II and the formula III for preparing the compound of the formula I are shown in the attached drawings.

The compounds of the formula I are obtained by reacting, in a manner known per se, compounds of the formula II,

wherein R is¹And R²Having the above meaning, 2 ', 3 ' -dihydroxypent-2 ' -yl-side chains in position 11 of the cyclic base skeleton are converted into acetyl side chains by glycolysis with oxygen (Glykolspalstung), and optionally the methyl residue R¹Introduction into the obtained R¹In compounds of the formula I which are hydrogen, or in the R obtained¹Cleavage of the methyl residue R in compounds of the formula I which are methyl¹And optionally converting the free compound of formula I into a stable acid addition salt thereof or converting the acid addition salt into the free compound of formula I.

The oxidative glycolysis of the 2 ', 3 ' -dihydroxypent-2 ' -yl-side chain at the 11-position of the cyclic base skeleton of the compound of the formula II can be carried out with a suitable oxidizing agent, such as lead tetraacetate, in a solvent suitable therefor. Suitable solvents are nonpolar or weakly polar solvents such as benzene, toluene or xylene. The reaction may be carried out at a temperature between 0 ℃ and 40 ℃, preferably at room temperature.

R obtained¹The compounds of the general formula I which are hydrogen can optionally be alkylated afterward in a known manner to give the corresponding N-methyl compounds. The alkylation reaction can be carried out in a known manner by reaction with a methyl halide or, as a reductive alkylation reaction, by reaction with formaldehyde under reducing conditions, for example in the presence of a reducing agent, for example in the presence of a complex borohydride such as sodium cyanoborohydride, sodium triacetoxyborohydride or sodium borohydride. If desired, the alkylation can also be carried out by reaction with a methyl halide, in particular methyl iodide, or with a methylsulfonate. The alkylation is suitably carried out in an organic solvent which is inert under the reaction conditions.Suitable solvents for the reductive alkylation are cyclic ethers such as tetrahydrofuran (═ THF) or dioxane, aromatic hydrocarbons such as toluene, or lower alcohols. The alkylation reaction may be carried out at a temperature between room temperature and the boiling temperature of the solvent. In the alkylation with a methyl derivative, for example a methyl halide such as methyl iodide, it is suitably carried out in the presence of a base such as an alkali metal carbonate or an organic tertiary amine.

If necessary, can be followed by R¹Cleavage of the methyl residue R in compounds of the formula I which are methyl¹. Demethylation can be accomplished in a known manner by treating the compound with a halogen, especially iodine and/or bromine, in an inert solvent in the presence of a suitable base. Suitable bases are, for example, alkali metal alcoholates, alkali metal hydroxides and alkali metal salts of weak organic acids.

The compounds of the formula I can be isolated and purified from the reaction mixture in a manner known per se. Acid addition salts can be converted in the usual manner into the free bases, which can be converted, if desired, in a known manner into pharmacologically tolerated acid addition salts. To avoid hydrolysis side reactions, it is appropriate to use only an equivalent dose of acid to form the salt.

As pharmacologically tolerated acid addition salts of the compounds of the general formula I, suitable are their salts with inorganic acids, for example carbonic acid, halogen acids, in particular hydrochloric acid, or with organic acids, for example lower aliphatic mono-or dicarboxylic acids, such as maleic acid, fumaric acid, lactic acid, tartaric acid or acetic acid.

R²The starting compounds of the formula II which are hydrogen are known from EP-B0550895 and can be prepared by the processes described therein.

R²Starting compounds of the formula II which are lower alkanoyl are prepared by reacting R²Compounds of the formula II with carboxylic acids of the formula III

R³-COOH III

Wherein R is³Lower alkyl, or a reactive derivative with the acid, in a manner known per se.

In particular, optionally mixed anhydrides and acid halides come into consideration as reactive derivatives of the acids of the general formula III. Thus, for example, it is possible to use the acid chlorides or acid bromides of the acids of the formula III, or mixed esters of the acids of the formula III with organic sulfonic acids, for example lower alkanesulfonic acids optionally substituted by halogen, such as methanesulfonic acid or trifluoromethanesulfonic acid, or with aromatic sulfonic acids, such as benzenesulfonic acid, or with benzenesulfonic acids substituted by lower alkyl or halogen, such as toluenesulfonic acid or bromobenzenesulfonic acid. As the acylation reaction, the reaction may be carried out in an organic solvent which is inert under the reaction conditions at a temperature between-20 ℃ and room temperature. Suitable solvents are di-lower alkyl ketones such as acetone, halogenated hydrocarbons such as dichloromethane, or aromatic hydrocarbons such as benzene or toluene, or cyclic ethers such as THF or dioxane, or mixtures of these solvents.

It is suitable, in particular when using anhydrides or mixed anhydrides of acids of the formula III and sulfonic acids as acylating agents, to carry out the acylation reaction in the presence of an acid-binding agent. Suitable as acid-binding agents are, for example, inorganic bases, for example alkali metal carbonates, such as potassium carbonate, or organic bases which are soluble in the reaction mixture, such as tertiary nitrogen bases, for example tertiary-lower alkylamines and pyridines, for example triethylamine, tripropylamine, N-methylmorpholine, pyridine, 4-dimethylaminopyridine, 4-diethylaminopyridine or 4-pyrrolidinopyridine.

Optionally adding to the obtained R¹Introduction of a methyl residue R into a Compound of formula II¹Or in the obtained R¹Cleavage of the methyl residue R in compounds of the formula II¹. This methylation or demethylation can be carried out in a manner known per se, for example under the conditions indicated for the introduction or cleavage of the methyl group in the compounds of the formula I.

The novel compounds of the general formula I and their physiologically tolerated acid addition salts have interesting pharmacological properties, in particular motilin-potentiating properties which stimulate gastrointestinal motility. Owing to its advantageous mode of action, it is characterized by particularly good oral effectiveness. They have no antibacterial effect, but have a highly selective affinity for motilin-receptors and have no actually relevant affinity for other receptors of the gastrointestinal tract, such as the epinephrine-, acetylcholine-, histamine-, dopamine-, or 5-hydroxytryptamine-receptors, in the dosage range in which motilin-potentiating is effective. These compounds have particularly good hepatic tolerance, which makes them suitable for long-term use.

In order to ensure a regular digestion of ingested food, the autonomic nervous system and gastrointestinal hormones act together in a healthy state to cause the gastrointestinal tract to produce regular contractile activity not only after ingestion of food but also in the fasting state. Motilin is a well-known gastrointestinal peptide hormone that stimulates gastrointestinal motility and induces coordinated activity throughout the gastrointestinal tract in the fasting state and after ingestion.

The compounds of general formula I have motilin-like physiological effects, as they act as potentiators for the motilin receptor. The compounds of formula I show excellent stimulating effects on the gastrointestinal tract and lower esophageal sphincter. They are particularly capable of accelerating gastric emptying, increasing gastric tone and increasing resting tone of the esophageal sphincter for a prolonged period of time. According to its motile-like mode of action, the material is suitable for the treatment of certain disease states associated with gastrointestinal motility disorders and/or the reflux of chyme from the stomach to the esophagus. That is, the indications of the compounds of the general formula I are gastroparesis, gastric dystonia, gastric emptying disorders and gastroesophageal reflux, dyspepsia and postoperative dyskinesia of various causes.

The gastrointestinal activity profile of the compounds of formula I was confirmed by standard test methods of pharmacology in vitro and in vivo.

Description of the test methods

1. The binding capacity of the test substance to the motilin receptor is determined.

The affinity of the compounds of formula I for the motilin receptor was determined in vitro using a homogenate fraction from the sinuses of rabbits. The displacement of radiolabeled iodinated motilin from the binding of motilin receptors by the test substance is measured.

Following the method of Borman et al (Regulatory Peptides)15(1986), page 143-153) for receptor binding studies. In a known manner, for example, analogously to Bloom et al (Scan. J. gastroenterol.)11(1976) pp 47-52) by enzymatic iodination of motilin using lactoperoxidase to prepare¹²⁵Motilin labeled with iodine.

To obtain the homogenate fraction used in the test from the rabbit sinuses, the sinuses dissociated from the mucosa were crushed and treated with 10 volumes of cold homogenization buffer (50mM Tris-HCl buffer, 250mM sucrose, 25mM KCl, 10mM MgCl) in 10 volumes₂pH7.4) was added with inhibitors (1mM iodoacetamide, 1. mu.M pepstatin, 0.1mM methylsulfonyl fluoride, 0.1g/l trypsin inhibitor, 0.25g/l bacitracin) and the resulting mixture was homogenized by rotating a homogenizer at 1500 rpm for 15 seconds. The homogenate was centrifuged at 1000g for 15 minutes, and the resulting residue was washed 4 times with homogenization buffer and then resuspended in 0.9% sodium chloride solution (in a volume equivalent to 5 times the sinus weight). The tissue fractions thus obtained are referred to as "crude membrane preparations" and are used for the experiments.

For binding assays 400. mu.l of buffer A (50mM Tris-HCl buffer, 1.5% BSA, 10mM MgCl)₂pH8.0) was diluted with 100. mu.l of motilin iodide in buffer B (10mM Tris-HCl buffer, 1% BSA, pH8) (final concentration 50pM) and incubated at 30 ℃ for 60 minutes. The reaction was stopped by adding 3.2ml of cold buffer B and bound and unbound motilin were separated from each other by centrifugation (1000g, 15 min). Centrifuging to obtain pelletThe residue was washed with buffer B and counted in a gamma counter. The displacement test was performed by adding test substances at increasing doses in the incubation medium. Using aqueous solutions as detection substance solutions by using 60X 10-^-4A molar aqueous stock solution is suitably diluted. The test substance, which is difficult to dissolve in water, is first dissolved in 60% ethanol, and the solution is then diluted with water in such an amount that the ethanol concentration in the test solution does not exceed 1.6% by volume. Determining IC as the detection substance from the obtained measurement data₅₀At which 50% of the specific binding of the iodinated motilin to the motilin receptor is inhibited. Calculating the corresponding pIC from the concentration₅₀The value is obtained. The pIC shown in Table 1 below was determined for the materials of examples 1 and 2 in accordance with the method described above₅₀The values given for the examples relate to the preparation examples described below.

TABLE 1

2. In vivo determination of the effect of the substance on gastric tone

Gastric tone plays an important role in gastric emptying. Increased gastric tone can accelerate gastric emptying.

The effect of the substance on gastric tension was measured on beagle dogs by means of an air pressure compensator (barosten) attached to the dog's stomach by a plastic pouch that measures the volume and pressure in the dog's stomach. The gastric volume is measured at a steady pressure in the stomach or the gastric pressure is measured at a steady volume in the stomach with a pressure compensator. The reduction of the volume of the stomach at a certain pressure and the increase of the pressure at a certain volume are measured when the stomach tension is increased. The change in stomach volume caused by these substances at steady pressure was measured in a test model applied to detect the increase in stomach tension caused by the substances. By ingestion of fat, the stomach of the test animal is relaxed, i.e. the gastric tone is reduced, and the stomach volume is correspondingly increased. The degree of reduction in the volume of the stomach, which is increased by the intake of fat, due to the re-rise of gastric tone after the intake of the substance is measured in% as a measure for the effect of increasing gastric tone.

In this test model, subcutaneous administration of the test substance of example 1 at a well tolerated dose of 2.15 μmol/kg reduced the increased gastric volume by 59.5% following fat intake. Oral administration of the test substance at an equivalent dose of 2.15 μmol/kg resulted in a significant reduction in gastric volume, thereby virtually completely inhibiting fat-induced relaxation of gastric volume. This result can be considered as evident evidence of the extremely high bioavailability, especially the high oral bioavailability, of the compounds of the invention.

3. In vivo determination of the Effect of test substances on the resting tension of the lower esophageal sphincter

The assay was performed on awake, fasted male beagles, which were placed with an esophageal fistula and a duodenal tube prior to the start of the trial. The pressure of the lower esophageal sphincter is measured by means of a perforated catheter system with a side hole to which a manometer and a recorder are connected. The catheter was introduced into the stomach through the esophageal fistula and then slowly withdrawn manually (pull-out tonometry). A peak was recorded when the catheter portion with the side hole passed through the high pressure area of the lower esophageal sphincter. From this peak, mmHg pressure was measured.

In this way, the basal esophageal sphincter pressure is first determined as a control value. The test substance is then administered orally and the pressure of the lower esophageal sphincter is measured at 2 minute intervals over a period of 60 minutes after 15 minutes. The increase in pressure of the test substance after administration is calculated as compared to a predetermined base pressure.

In this test, the basal tone of the esophageal sphincter was raised 143% after the application of 0.464. mu. mol/kg of the compound of example 1. This effect was maintained throughout the 60 minute test.

In view of their action in the gastrointestinal tract, the compounds of the general formula I are suitable as medicaments in gastroenterology for the prophylaxis and treatment of gastrointestinal motility disorders in larger mammals, in particular in humans.

The dosage to be applied may vary from individual to individual and naturally from one state to another and from one mode of administration to another. For example, parenteral dosage forms typically contain less active than oral dosage forms. But generally the pharmaceutical forms suitable for larger mammals, especially humans, contain from 1 to 100mg of active substance per unit dose.

The compounds of the general formula I can be included as medicaments in galenic preparations such as tablets, capsules, suppositories or solutions with customary pharmaceutical adjuvants. These galenic preparations can be prepared in a known manner using customary solid carrier substances, for example lactose, starch or talc, or liquid diluents, for example water, fatty oils, or liquid paraffin, and using customary pharmaceutical adjuvants, for example tablet disintegrants, solubilizers or storage agents.

The following examples further illustrate the invention, but are not intended to limit its scope.

Example 1：

(2R, 3S, 4S, 5R, 6R, 10R, 11R) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribohexopyranosyl) -oxy]-5- [3, 4, 6-Trideoxy-3- (N-methyl-N-isopropylamino) -beta-D-xylohexopyranosyl) -oxy]-2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1]Tridec-8-en-1-one (compound of formula I, R)¹Methyl, R²H ═ H)

A) 100g of [2R (2 'R, 3' R), 3S, 4S, 5R, 6R, 10R, 11R]-11- (2 ', 3 ' -dihydroxypent-2 ' -yl) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribohexopyranosyl) -oxy]-5- [3, 4, 6-Trideoxy-3- (N-methyl-N-isopropylamino) -beta-D-xylohexopyranosyl) -oxy]-2, 4, 6, 8, 10-pentamethyl-12, 13-dioxabicyclo [8.2.1] ring]Tridec-8-en-1-one (═ compounds of formula II, R¹Is a nailRadical, R²Hydrogen) in 2500ml of toluene under nitrogen atmosphere. To this solution 100.0g of lead tetraacetate was added and the resulting suspension was stirred at room temperature for 5 hours. The reaction mixture was then washed successively with saturated sodium bicarbonate solution and then with water several times until the wash water was neutral. The organic phase is dried over sodium sulfate and concentrated to dryness under reduced pressure. The residue was chromatographed on silica gel (eluent: methyl-tert-butyl ether ═ MTBE) to give 81.9g of the title compound as a white powder with a melting point of 198-]_D ²⁰-24.6 ° (c ═ 1.0 in CH₂Cl₂In (1).

B) 1.1g of the compound obtained above was dissolved in 1ml of acetonitrile. To this solution 0.17g malonic acid was added and heated to 60-70 ℃. After the solid components dissolved, 10ml of MTBE was added, followed by heating at the boiling point under reflux cooling for 5 minutes. 10ml of MTBE were then added again and the mixture was allowed to cool to room temperature with stirring. The crystalline material precipitated was filtered off from the solution, washed 2 times with 10ml of MTBE and dried in vacuo at 60 ℃. 1.2g of the monomalonate salt of the title compound are obtained with a melting point of 115.6-174.6 ℃ (imprecise).

Example 2:

(2R, 3S, 4S, 5R, 6R, 10R, 11R) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribohexopyranosyl) -oxy]-5- [3, 4, 6-trideoxy-2-O-acetyl-3- (N-methyl-N-isopropylamino) - β -D-xylopyranosyl) -oxy]-2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1]Tridec-8-en-1-one (compound of formula I, R)¹Methyl, R²Arbute)

A) 210.0g of the starting compound from example 1 (═ compound of general formula II, R)¹Methyl, R²Hydrogen) was dissolved in 2.4l of acetone under nitrogen atmosphere and mixed with 85.8g of potassium carbonate. 63.4g of acetic anhydride was added to this precursor solution, and the obtained suspension was stirred at room temperature for 20 hours. The reaction mixture was then poured into a mixture of 2400g of ice and 1000ml of waterImmersed and stirred for 30 minutes. The aqueous phase was extracted 3 times with ethyl acetate, the organic phases were combined and the excess solvent was evaporated in vacuo. 200g of [2R (2 'R, 3' R), 3S, 4S, 5R, 6R, 10R, 11R ] are obtained from the crude product obtained by crystallization of n-pentane]-11- (2 ', 3 ' -dihydroxypent-2 ' -yl) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl-alpha-L-ribohexopyranosyl) -oxy]-5- [3, 4, 6-trideoxy-2-O-acetyl-3- (N-methyl-N-isopropylamino) - β -D-xylopyranosyl) -oxy]-2, 4, 6, 8, 10-pentamethyl-12, 13-dioxabicyclo [8.2.1] ring]Tridec-8-en-1-one (═ compounds of formula II, R¹Methyl, R²Acetyl) melting point 128-.

B) 10.1g of the product obtained above are reacted with 9.1g of lead tetraacetate according to the method described in example 1. 6.0g of the title compound are obtained as a white solid with a melting point of 164 ℃ and an optical rotation [ alpha ]]_D ²⁰-23.2 ° (c 1.0 in CH)₂Cl₂In (1).

Example I:

a capsule containing (2R, 3S, 4S, 5R, 6R, 10R, 11R) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl- α -L-ribohexopyranosyl) -oxy ] -5- [3, 4, 6-trideoxy-3- (N-methyl-N-isopropylamino) - β -D-xylohexopyranosyl) -oxy ] -2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1] tridec-8-en-1-one:

capsules containing the active substance per capsule were prepared using the following adjuvants and contents:

(2R, 3S, 4S, 5R, 6R, 10R, 11R) -3- [ (2, 6-dideoxy-3-C-methyl-3-O-methyl-. alpha. -L-ribohexopyranosyl) -oxy ] -5- [3, 4, 6-trideoxy-3- (N-methyl-N-isopropylamino) -beta-D-xylohexopyranosyl) -oxy ] -2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1] tridec-8-en-1-one 20mg

Corn starch 60mg

Lactose 301mg

Proper amount of ethyl acetate (═ EE)

The active substance, corn starch and lactose are processed to a homogeneous pasty mixture with the addition of ethyl acetate. The paste was pulverized and the granules formed were placed on a suitable plate and dried at 45 ℃ to remove the solvent. The dried granules were passed through a pulverizer and then mixed in a mixer with the following adjuvants:

talcum powder 5mg

Magnesium stearate 5mg

Corn starch 9mg

Then, the mixture was filled into 400mg capsules (capsule size: 0).

Claims (5)

1. (2R, 3S, 4S, 5R, 6R, 10R, 11R) -2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1] tridec-8-en-1-one compounds of the general formula I and their physiologically tolerated acid addition salts

Wherein

R¹Is hydrogen or methyl

R²Is hydrogen or contains branched or unbranched C_1-4Acyl of an alkyl group.

2. A compound according to claim 1, wherein R is¹Is methyl.

3. A compound according to claim 1 or 2, wherein R²Is hydrogen.

4. A medicament containing a pharmacologically active amount of a compound according to claim 1 and customary pharmaceutical adjuvants and/or carrier materials.

5. A process for the preparation of (2R, 3S, 4S, 5R, 6R, 10R, 11R) -2, 4, 6, 8, 10-pentamethyl-11-acetyl-12, 13-dioxabicyclo [8.2.1] tridec-8-en-1-one compounds of the general formula I and their physiologically tolerated acid addition salts

Wherein

R¹Is hydrogen or methyl

R²Is hydrogen or contains branched or unbranched C_1-4The acyl group of the alkyl group,

characterized in that, in the compound of the general formula II,

wherein R is¹And R²Having the above meaning, the 2 ', 3 ' -dihydroxypent-2 ' -yl-side chain at the 11-position of the cyclic skeleton is converted into an acetyl side chain by glycolysis with oxygen,

and optionally a methyl residue R¹Introduction into the obtained R¹In compounds of the formula I which are hydrogen, or in the R obtained¹Cleavage of the methyl residue R in compounds of the formula I which are methyl¹，

And optionally converting the free compound of formula I into a stable acid addition salt thereof or converting the acid addition salt into the free compound of formula I.