KR20020069188A - Treatment of heart rhythm disturbances with n6-substituted-5'-(n-substituted)carboxamidoadenosines - Google Patents

Abstract

The present invention discloses a method of treating by administering N ⁶ -substituted-5 '-(N-substituted) carboxamidoadenosine to a mammal in need thereof. More specifically, the present invention relates to inducing negative metastatic action and / or negative variable action comprising administering to the mammal an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt or ester thereof The present invention relates to a method of treating heart rhythm disturbances in mammals.

Formula I

Wherein R ₁ is C _3-7 secondary alkyl or C _3-8 cycloalkyl and R ₂ is C _1-4 alkyl or C _3-5 cycloalkyl. The invention also relates to novel formulations comprising such compounds.

Description

Treatment of heart rhythm disturbance with N6-substituted-5 '-(N-substituted) carboxamidoadenosine {TREATMENT OF HEART RHYTHM DISTURBANCES WITH N6-SUBSTITUTED-5'-(N-SUBSTITUTED) CARBOXAMIDOADENOSINES}

In the heart of a mammal, electrical shock in the sinotrial (SA) nodules is transmitted through the atrioventricular (AV) nodules to the ventricles to initiate blood vessel contraction to circulate blood. If the heart is functioning normally, persistent rhythmic shocks cause a regular heartbeat.

Various dysfunctions occur in the heart, disrupting regular heartbeat patterns and causing arrhythmias. For example, an excessively fast heartbeat can cause symptoms that are defined as slack. Poor pulsation can be caused by excessively rapid release from a dysfunctional SA nodule, electrical shock through a negative path that promotes pulsation before pulsation normally occurs, or reentry of an impact in an AV nodule. The disorder in this case is called paroxsymal supraventricular tachycardia (PSVT), which in some patients can lead to congestive heart failure. Another cardiac rhythm disturbance, called atrial fibrillation / flutter (AF), is characterized by a fast, irregular rhythm of the atria and is associated with an increased incidence of stroke. The cardiac rhythm disturbances can be classified as ventricular tachycardia. Symptoms of such disorders include palpitations, fatigue, difficulty breathing, as well as malaise due to dizziness and / or dizziness.

Adenosine is well known for slowing heart rate (negative variable effects) and slowing shock conduction through AV nodules (negative substation effect) (Berne et al. US Pat. No. 4,673,563; Belardinelli et al., Journal of Pharmacology and Experimental) Therapeutics 271: 1371 (1994)]. Adenosine is currently used for the treatment of PSVT, but has been shown to be ineffective in converting AF to normal sinus rhythm.

Adenosine acts through a number of receptor subtypes called A ₁ , A _2A , A _2B and A ₃ . Adenosine A ₁ receptors mediate the anosine and negative transduction effects of adenosine as well as directly inhibit atrial (not ventricular) contractility. Adenosine A _2A receptors mediate coronary dilatation of adenosine. The location and function of adenosine A _2B and A ₃ receptors in the heart are not well understood.

PSVT can result from abnormally frequent impacts affecting AV nodules, and adenosine A ₁ receptors mediate the negative transduction effects of adenosine, so one method of terminating PSTV is selective adenosine to slow shock conduction through AV nodules. Using A ₁ receptor agonists (Belardinelli et al., Journal of Pharmacoloy and Experimental Therapeutics 271: 1371 (1994); Snowdy et al., British Journal of Pharmacology 126: 137 (1999)).

However, the adenosine A ₁ receptor agonists studied so far for this purpose lacked the required efficacy, selectivity, oral bioavailability and / or pharmacokinetic activity. In addition, prior art adenosine A ₁ agonists have been shown to cause hypotension, a side effect that exacerbates symptoms in patients with cardiac rhythm disturbances.

A series of N ⁶ -substituted-5 ′-(N-substituted) carboxamidoadenosine derivatives has already been disclosed. These compounds are selective adenosine A ₁ receptor agonists useful as vasodilators or anti-hypertensive agents (US Pat. No. 5,310,731 to Olsson, R. and Thompson, R.).

The present invention provides for the use of certain adenosine A ₁ agonists belonging to a class of N ⁶ -substituted-5 '-(N-substituted) carboxamidoadenosine in the treatment of cardiac rhythm disturbances in mammals and this novel use. It relates to a new formulation for.

FIG. 1 shows the negative morphogenic and negative transduction action of ethyl N ⁶ -cyclopentyladenosine-5′-uronamide (Compound A) in spontaneously beating heart isolated from guinea pigs; HR = heart rate, bpm = heart rate per minute, msec = 10 ^-3 seconds. Compound A reduced concentration of AV conduction and the maximum increase in AV interval was 34% above the default value. Compound A also reduced heart rate in a concentration dependent manner, with an EC ₅₀ value of 3.2 nM and a maximum reduction in heart rate of 58%.

FIG. 2 shows the negative transduction action of Compound A in the heart model of paroxysmal ventricular tachycardia (PSVT) isolated from guinea pigs; HR = heart rate, bpm = heart rate per minute, msec = 10 ^-3 seconds. Compound A with an average concentration of 2 nM, which had little effect on AV interval at 200 bpm beats, induced AV blocks within 30 seconds at 300 bpm beats. As the heart rate dropped to 200 bpm, the AV interval returned to almost normal levels. Therefore, the effect of Compound A in this experimental model of PSVT is rate dependent, such that Compound A increases the AV conduction interval even more at faster beat rates.

FIG. 3 shows negative translocation and coronary vasodilation action of Compound A in the heart pulsating by electricity isolated from guinea pigs; CPF = coronary perfusion flow, ml = milliliters. Compound A with an average concentration of 0.76 nM increased the AV interval up to 23% on average under a pulsating condition of 300-360 beats per minute and induced cardiac block at an average concentration of 1.09 nM. Under the same pulsating conditions as above, Compound A concentration-dependently increased coronary perfusate flow from an average flow rate of 8.5 ml / min to an average flow rate of 14.2 ml / min. The mean concentration of Compound A (EC ₅₀ ) causing a 50% maximum increase in coronary perfusion flow was 32 nM. Thus, Compound A was 40 times more potent in reducing AV conduction than increasing coronary perfusion fluid flow.

Detailed description of the invention

The present invention has found that the particular N ⁶ -substituted-5 '-(N-substituted) carboxamidoadenosine, defined by Formula I above, possesses particularly desirable pharmacological properties useful for the treatment of cardiac rhythm disturbances. These compounds possess one or more of surprising efficacy, selectivity, oral bioavailability and pharmacokinetic activity.

Accordingly, the present invention comprises administering an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt or ester thereof to a mammal in need of treatment for cardiac rhythm disturbance, negative metastatic action, negative variable action Or a method of treating cardiac rhythm disturbance in a mammal that would benefit from inducing them together.

Formula I

Wherein R ₁ is C _3-7 secondary alkyl or C _3-8 cycloalkyl and R ₂ is C _1-4 alkyl, C _1-4 hydroxyalkyl or C _3-5 cycloalkyl.

Useful R ₁ include isopropyl, 2-butyl, 2-pentyl, 3-pentyl, 2-hexyl, 3-hexyl, 2-heptyl, 3-heptyl, 4-heptyl, cyclopropyl, cyclopentyl, cyclohexyl, cyclo Heptyl and norobonyl. Preferred as R ₁ include 3-pentyl, cyclopentyl or norbornyl, more preferably 3-pentyl or cyclopentyl. Useful as R ₂ are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, t-butyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, cyclopropyl, cyclobutyl and cyclopentyl . Preferred R ₂ are methyl, ethyl, hydroxyethyl, isopropyl or cyclopropyl, more preferably ethyl or cyclopropyl.

Useful compounds are

N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine,

N ⁶ -cyclopentyl-5 '-(N-cyclopropyl) carboxamidoadenosine,

N ^6- (3-pentyl) -5 '-(N-ethyl) carboxamidoadenosine,

N ⁶ -cyclopentyl-5 '-(N-methyl) carboxamidoadenosine, or

As well as N ⁶ -cyclopentyl-5 '-(Nt-butyl) carboxamidoadenosine,

Pharmaceutically acceptable salts and esters thereof.

The present invention utilizes the administration of N ⁶ -substituted-5 ′-(N-substituted) carboxamidoadenosine of Formula I to treat cardiac rhythm disturbance in mammals. Treatment of cardiac rhythm disturbances and selective prophylactic maintenance to minimize the further occurrence of cardiac rhythm disturbances are both considered useful aspects of the present invention. Such cardiac rhythm disturbances include ventricular tachycardia such as paroxysmal ventricular tachycardia (PSVT) and atrial fibrillation / atrial fibrillation (AF).

In a preferred aspect of the present invention, about 0.001 μg / kg to about 100 μg / kg, preferably about 0.005 μg / kg to about 1 μg / kg, more preferably about 0.01 μg / kg to about 0.5 μg / kg Cardiac rhythm disturbance is treated by intravenous infusion of N ⁶ -substituted-5 ′-(N-substituted) carboxamidoadenosine. The infusion period can be tailored to the individual patient. Useful infusion periods are from about 2 to about 60 minutes, preferably from about 10 minutes to about 30 minutes. Thereafter, optionally, N ⁶ -substituted-5 '-(N-substituted) carboxamidoadenosine in a suitable pharmaceutical composition can be administered orally, with a dosage of about 0.001 μg / kg to about 100 μg / kg, Preferably from about 0.01 μg / kg to about 10 μg / kg, more preferably from about 0.1 μg / kg to about 8 μg / kg. The dosage is preferably adjusted to optimize the response of each patient. Oral administration is particularly useful as a prophylactic maintenance treatment to minimize the idiopathic occurrence of such cardiac rhythm disturbances.

The most preferred intravenous dose is about 0.1 to about 10 μg / kg / min, the most preferred oral dose is about 1 to about 50 μg / kg, and may be administered up to four times per day as needed.

Most preferred compounds for this use are N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine and N ⁶ -cyclopentyl-5'-(N-cyclopropyl) carboxamidoadenosine.

N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine (compound of formula I wherein R ₁ is cyclopentyl and R ₂ is ethyl) is 1- [6- (cyclopentylamino) -9H- Also known as furin-9-yl] -1-deoxy-N-ethyl-β-D-ribofuranuronamide or N ⁶ -cyclopentyladenosine-5'-ethylcarboxamide.

In addition, a comparison of (a) the ability of a compound of formula (I) to slow shock conduction in the heart, as evidenced by its negative translocation activity and its negative transmutation activity, and (b) its hypotensive activity or lack of this activity, It was found that there was a separation point. Thus, these compounds can be administered in a manner that treats heart rhythm disturbances by reducing heart rate without affecting blood pressure. This is a very desirable feature and has not been presented in the prior art. Based on the prior art, these compounds are predicted to have hypotensive activity. Administration of adenosine A ₁ agonists is expected to exacerbate symptoms and complicate therapeutic adjustments in patients with cardiac rhythm disturbances.

The inventors also found that the negative translocation effect of the compounds of formula (I) is dependent on heart rate. As the heart rate is increased, the potency of the compounds of formula (I) is increased so that the desired negative transduction effects can be used for therapeutic modulation, i.e., these compounds are used under conditions where their action is most needed (i.e., poor). It was found to exhibit the most potent therapeutic action. This pharmacological profile provides the option of administering the compound to the patient at a concentration that would or would not act minimally on the heart under normal conditions, but at a concentration that would indicate a therapeutic action at abnormally fast heart rates. .

Compounds of the invention can be synthesized according to the methods described in US Pat. Nos. 5,310,731 and 4,868,160. For example, the compound of formula (I) may be treated with 2 ', 3'-0-isopropylideneinosine-5'-uronic acid with an appropriate inorganic acid halide (e.g. thionyl chloride) as an intermediate 6-chloro-9- [2,3-O-isopropylidene-β-D-ribofuranosyl-5-uronic acid chloride] -9H-purine can be produced. Intermediate 6-Chloro-9- [2,3-O-isopropylidene-β-D-ribofuranosyl-5-uronic acid chloride] -9H-purine (or thionyl bromide is substituted for thionyl chloride If used, the corresponding bromide) does not need to be separated in its pure state.

Acid chloride portion of 6-chloro-9- [2,3-O-isopropylidene-β-D-ribofuranosyl-5-uronic acid chloride] -9H-purine (or acid bromide of the corresponding bromo-analogue) ) Is much more easily substituted by the nucleophilic reactant than the halide group at position 6 of the purine moiety. Thus, according to the process of the invention, 6-chloro-9- [2,3-O-isopropylidene-β-D-ribofuranosyl-5-uronic acid chloride] -9H-purine is represented by the formula R ₁ -NH _2, the first pro-react with nucleophilic reactants to produce a carboxamide substituted intermediate material, wherein the halide is retained in the 6-position of the purine portion.

The intermediate, substituted carboxamide, is then reacted with a nucleophile of formula R ₂ -NH ₂ , and free acid groups are present at the 2 'and 3' positions of the ribofuranose moiety when the isopropylidene blocker is removed with acid. Compounds of the invention are produced. Instead of isopropylidene blockers, other acid stable blockers may be used to protect the 2'-OH and 3'-OH groups of the ribofuranose moiety during the treatment step with an inorganic acid halide.

Pharmaceutically acceptable salts (in the form of water-soluble, fat-soluble, or dispersible products) of the compounds of formula (I) include, for example, conventional non-toxic salts or quaternary ammonium salts formed from inorganic or organic acids, or inorganic or organic bases. Can be mentioned. Examples of such acid addition salts are acetate, adipate, alginate, aspartate, benzoate, benzenesulfonate, bisulfate, butyrate, citrate, camphorate, camphorsulfonate, cyclopentanepropionate, digluconate, Dodecyl sulfate, ethanesulfonate, fumarate, glucoheptanoate, glycerophosphate, hemisulfate, heptanoate, hexanoate, hydrochloride, hydrobromide, hydroiodide, 2-hydroxyethanesulfonate, Lactate, malate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oxalate, pamoate, pectinate, persulfate, 3-phenylpropionate, picrate, pivalate, propio Nates, succinates, sulfates, tartrates, thiocyanates, tosylates, and undecanoates. have. Base salts include ammonium salts, alkali metal salts (e.g. sodium and potassium salts), alkaline earth metal salts (e.g. calcium and magnesium salts), salts with organic bases (e.g. dicyclohexylamine salts, N-methyl-D -Glucamine), and salts with amino acids (eg arginine, lysine). In addition, basic nitrogen-containing groups are also lower alkyl halides such as methyl, ethyl, propyl and butyl chloride, methyl, ethyl, propyl and butyl bromide, and methyl, ethyl, propyl and butyl iodide; Dialkyl sulfates (eg, dimethyl, diethyl, dibutyl and diamyl sulfates); Long chain halides (eg decyl, lauryl, myristyl and stearyl chloride; decyl, lauryl, myristyl and stearyl bromide; and decyl, lauryl, myristyl and stearyl iodide); Quaternized with aralkyl halides such as benzyl and phenethyl bromide, and the like.

Pharmaceutically acceptable esters of compounds of formula I include organic acid esters of hydroxyl groups at the 2 'and 3' positions of the ribofuranose moiety. It is preferable that the ester group is of a type that hydrolyzes relatively easily under physiological conditions. Useful esters include those having an acyl group selected from the group consisting of acetyl, propionyl, butyryl and benzoyl groups.

The invention also relates to the use of a compound of formula (I) in the manufacture of a medicament for the treatment of cardiac rhythm disturbances in a mammal, which benefits from negative metastatic action, negative metabolic action, or induction thereof. will be.

The pharmaceutical compositions of the present invention may be administered in any manner to achieve the intended purpose. For example, administration can be via the parenteral, subcutaneous, intravenous, intramuscular, intraperitoneal, transdermal, buccal or ocular route. Alternatively, or in parallel, oral administration may be used. Dosages will depend on the age, health and weight of the recipient, the type of concomitant treatment (if used), the frequency of treatment and the nature of the desired effect. Preferred routes of administration are intravenous and oral administration.

Cardiac rhythm disturbances can be dangerous for cardiac tissue and require rapid onset of action. Thus, intravenous injection is the most preferred route of administration. Intravenous administration may consist of a single injection, subsequent administration of a low dose of maintenance dose, continuous injection of a low concentration of maintenance dose, continuous injection of low dose of maintenance dose, or other type of administration as appropriate for the needs of the subject to be treated. Can be.

The second preferred route of administration is oral administration. Certain compounds of the invention have very high oral bioavailability. Oral administration is a particularly preferred route for providing a maintenance dose of a compound of the invention. Since the negative electroconductive effect of the compounds of the present invention increases with increasing heart rate, an oral dose that exhibits a therapeutic effect when the patient's heart rate is too fast can be administered.

The pharmaceutical formulation is preferably present in unit dosage form. In this form, the formulation is divided into unit doses containing appropriate amounts of the active ingredient. The unit dosage form may be a packaged preparation, ie a package containing discrete quantities of preparation, such as packet tablets, capsules and powders in vials or ampoules. The unit dosage form may be the capsule, cachet or tablet itself, or may be in packaged form containing any of these in the appropriate number.

The amount of active compound in the unit dose of the formulation can be varied or adjusted to 0.01 to 1 mg, preferably 0.1 to 0.5 mg, depending on the particular use and the potency of the active ingredient. If desired, the composition may contain other compatible therapeutic agents. Examples of useful therapeutic agents that may be co-administered with the active compounds of the invention include verapamil, quinidine, procaineamide, diisopyramid, plecanide, ibutylide, dofetilide, amiodarone, sotalol, diltiazem, Esmolol, propranolol, metoprolol and digoxin. In addition, DC electrical defibrillation and surgical surgical procedures are useful for terminating atrial fibrillation and can be used with the administration of a compound of the present invention.

In the aforementioned therapeutic uses, the dosage range for a subject mammal weighing 70 kg is about 0.00035 to about 1 mg / kg body weight / day or preferably about 0.0007 to about 0.6 mg / kg body weight / day. However, the dosage may vary depending on the needs of the patient, the severity of the condition to be treated and the compound used.

Determination of the appropriate dosage for a particular situation is within the skill of the art. It is common to begin treatment at a dosage lower than the optimal dose of the compound. The dosage is then increased by increasing the amount in small increments until an optimum effect is obtained under a given environment. For convenience, the total daily dose may be divided and the divided doses administered as needed during the day.

This novel pharmaceutical preparation may comprise, in addition to the pharmacologically active ingredient, a suitable pharmaceutically acceptable carrier comprising excipients and auxiliaries which facilitate processing of the active ingredients into pharmaceutically usable preparations.

The pharmaceutical preparations of the present invention are prepared by methods known per se, such as conventional mixing, granulating, sugar preparation, dissolution or lyophilization processes. Thus, oral pharmaceutical preparations can be prepared by combining the active compound with a solid excipient, optionally milling this mixture and processing the granule mixture, and then adding appropriate auxiliaries to tablets or sugar cores, if necessary.

Suitable excipients include, in particular, fillers such as sugars (eg lactose or sucrose, mannitol or sorbitol), cellulose preparations and / or calcium phosphates (eg tricalcium phosphate or calcium hydrogen phosphate) and binders such as starch pastes ( Eg, corn starch, wheat starch, rice starch, potato starch and the like), gelatin, tragacanth, methyl cellulose, hydroxypropylmethylcellulose, sodium carboxymethylcellulose and / or polyvinyl pyrrolidone. If desired, in addition to disintegrants such as starch described above, carboxymethyl-starch, crosslinked polyvinylpyrrolidone, agar, or alginic acid or salts thereof (eg sodium alginate) can be added. Auxiliaries include in particular flow regulators and lubricants, for example silica, talc, stearic acid or salts thereof (eg magnesium stearate or calcium stearate) and / or polyethylene glycols. The sugar core can be appropriately coated to withstand gastric acid as necessary. For this purpose, concentrated saccharides may be used, which may optionally include gum arabic, talc, polyvinyl pyrrolidone, polyethylene glycol and / or titanium dioxide, lacquer solutions and suitable organic solvents or solvent mixtures. To prepare a coating resistant to gastric acid, a suitable cellulose preparation such as acetylcellulose phthalate or a solution of hydroxypropylmethyl-cellulose phthalate is used. For example, dye substances or pigments may be added to tablets or sugar coatings for display or to indicate a combination of active compound doses.

Other pharmaceutical preparations that can be used orally include push-fit capsules made of gelatin, soft sealed capsules made of gelatin and plasticizers (eg glycerol or sorbitol). Push-fit capsules are active compounds in granular form, which can be mixed with fillers (e.g. lactose), binders (e.g. starches) and / or lubricants (e.g. talc or magnesium stearate), optionally with stabilizers. It may include. In soft capsules, the active compound is preferably dissolved or suspended in a suitable liquid (eg fatty oil or liquid paraffin). In addition, stabilizers may be added.

Formulations suitable for parenteral administration include aqueous solutions of the active compounds in water-soluble forms such as water-soluble salts, alkaline solutions and cyclodextrin containing complexes. One or more modified or unmodified cyclodextrins may be used to stabilize and increase the water solubility of the compounds of the present invention. Cyclodextrins useful for this purpose are disclosed in US Pat. Nos. 4,727,064, 4,764,604 and 5,024,998. Formulations suitable for parenteral administration can be adjusted to the appropriate pH as needed to provide the maximum stability and / or solubility of the active compound. Osmoticity of such formulations can be controlled with known osmotic modulators. The concentration of the active substance in the parenteral preparation of the present invention is about 0.1 to about 500 μg / ml, preferably about 1 to about 250 μg / ml, more preferably about 5 to about 50 μg / ml. Parenteral preparations may be liquids, ready-to-use preparations or lyophilized materials which may be reconstituted prior to administration.

In addition, suspensions of the active compounds can be administered as appropriate oily injection suspensions. Suitable lipophilic solvents or excipients include fatty oils such as sesame oil, or synthetic fatty acid esters such as ethyl oleate or triglycerides or polyethylene glycol-400 (the compounds are soluble in PEG-400). Aqueous injection suspensions may include substances that increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, and / or dextran. Optionally, this suspension may also contain a stabilizer.

Summary of the Invention

The present invention comprises administering an effective amount of a compound of formula (I) or a pharmaceutically acceptable salt or ester thereof to a mammal in need of treatment for cardiac rhythm disturbance, or negative metamorphic action, or A method of treating cardiac rhythm disturbances in mammals that benefits from inducing them together.

Wherein R ₁ is C _3-7 secondary alkyl or C _3-8 cycloalkyl and R ₂ is C _1-4 alkyl, C _1-4 hydroxyalkyl or C _3-5 cycloalkyl.

Cardiac rhythm disturbances include ventricular tachycardia such as paroxysmal ventricular tachycardia (PSVT) and atrial fibrillation / atrial fibrillation (AF).

The invention also relates to novel intravenous and oral formulations comprising certain concentrations of one or more compounds of formula (I).

The invention also relates to the use of a compound of formula (I) in the manufacture of a medicament for the treatment of cardiac rhythm disturbances in a mammal, which benefits from negative metastatic action, negative metabolic action, or induction thereof. will be.

The following examples are intended to illustrate the methods and compositions of the present invention and do not limit the invention. Appropriate modifications and adaptations of the various conditions and parameters generally encountered and understood by those skilled in the art are within the spirit and scope of the invention.

Concentration dose-effect curve data using GraphPad PRIZM ^™ software was fitted to the sigmoidal curve, resulting in a concentration or dose of test compound that results in 50% of the maximally obtainable response to activation of adenosine A ₁ receptor, i.e., test In vitro EC ₅₀ or in vivo ED ₅₀ values were obtained. The response measured for each dose was the peak bradycardia of the stagnant negative myotrophic response to the cumulative addition of test compound in the isolated left atrium and the response to round vein injection of the test compound in conscious rats. Oral bioavailability was estimated from pharmacokinetic responses using the formula (Reaction AUC _Oral / Reaction AUC _iv ) (Dose _iv / Dose _Oral ), where Reaction AUC was the area under the curve for test compound induced bradycardia over time. to be.

Example 1

In vitro activity

Male Sprague-Dawley rats weighing 200-350 g were sacrificed and the hearts were quickly isolated and placed in luke's Krebs-Henzelite buffer. The left atrium is excised from the heart and suspended in a covered container containing 30 ml of separated tracheal treatment filled with Krebs-Henzelite buffer, infused with 95% O ₂ /5% CO ₂ and maintained at 37 ° C. I was. The tissue was connected to a force pre-transducer under 1 g resting tension. Stimulation of tissues was induced by stimulating the atria with 1 Hz of electricity and a maximum voltage for 1 msec.

The adenosine A ₁ agonist was added to the tracheal treatment solution gradually increasing the concentration until contractility decreased. Because adenosine A ₁ agonists have a minimal direct impact on the negative myoplastic action of the rat atrium, maximizing the negative myoplastic response requires stimulating β-adrenergic receptors that induce a positive myoplastic action to facilitate measurement. There is. Under these conditions, the A ₁ adenosine operation acting on the A ₁ receptor is reduced indirectly the β- adrenergic-mediated positive muscle contractility. Therefore, β-adrenergic agonist isoproterenol (10 ^-8 M) was added to the tracheal treatment about 15 minutes before the adenosine A ₁ agonist was added.

The results are shown in the table below.

compound R ₁ R ₂ EC ₅₀ (nM) A Cyclopentyl ethyl 15.5 B Cyclopentyl Hydroxyethyl 11.2 C Cyclopentyl Cyclopropyl 3.8 D Cyclopentyl methyl 19.1 E Cyclopentyl Isopropyl 11.0 F Cyclopentyl t-butyl 72.4 G Cyclopentyl profile 25.1 H Norbornyl Hydroxyethyl 3.8 I 3-pentyl ethyl 7.9 J 3-pentyl Hydroxyethyl 21.8

The data demonstrate that the series of compounds has high in vitro potency against adenosine A ₁ receptor.

Example 2

In vivo activity

Male Sprague-Dawley rats were anesthetized by intraperitoneal injection of 50 mg / kg of sodium pentobarbital, and an internal catheter was surgically implanted into the carotid and jugular vein two days before each experiment. During all subsequent experiments, rats were conscious and not restrained. The carotid cannula was attached to a pressure transducer and blood pressure was measured throughout each experiment using a Grass multipurpose recorder. The heart rate was derived from the blood pressure signal using the Grass Sok. The parameters measured were allowed to stabilize for 30-90 minutes before the test compound was administered.

Test compounds were administered by oral gavage using a curved spherical oral cannula or intravenously via a jugular vein indwelling catheter. Rats administered orally were fasted the night before dosing and water was given at random. Since the heart rate response rapidly declined to the default value after intravenous administration of the test compound, each rat was administered one or more test compounds. However, the response to oral administration of test compounds lasted for a long time, so each rat was administered only once.

The area under the bradycardia versus time curve after intravenous administration (AUC) and AUC after oral administration was used as a measure of oral bioavailability. The results are shown in the table below.

compound R ₁ R ₂ ED ₅₀ (nmol / kg) Oral Bioavailability A Cyclopentyl ethyl 8.3 53% B Cyclopentyl Hydroxyethyl 7.4 8.4% C Cyclopentyl Cyclopropyl 9.3 38% D Cyclopentyl methyl 3.9 20% E Cyclopentyl Isopropyl 3.4 28% F Cyclopentyl t-butyl 363 34% G Cyclopentyl profile 32.3 14% H Norbornyl Hydroxyethyl 3.4 2.3% I 3-pentyl ethyl 7.9 20% J 3-pentyl Hydroxyethyl 8.3 9.9%

In order to facilitate long-term administration, substantial oral bioavailability is a very important feature for the compound. From these data, it can be seen that the 5'-hydroxyethyl substituent interferes with oral bioavailability, and the 5'-alkyl-substituted derivatives (the alkyl contains 1 to 3 carbons) possess good oral activity. .

Example 3

Distinction between Coronary Vasodilation and Negative Transformer Activity

Hearts isolated from rats were prepared according to Langendorff's method, and the coronary vasculature was perfused in a retrograde manner through the aorta at constant pressure. Coronary blood flow was determined by measuring the volume of fluid flowing from the heart. The heart rate electrically beats the right atrium to maintain 360 beats per minute. Atrioventricular (AV) conductance was measured as the time from atrial stimulation to onset of ventricular polarization (S-V interval).

Compound A concentration-dependently reduced AV conduction, with a maximum SV interval increase at an average concentration of 6.8 nM and AV conduction occlusion at an average concentration of 8.3 nM. At these concentrations, Compound A did not affect coronary blood flow. This demonstrates that Compound A is a potent adenosine A ₁ receptor agonist that induces maximal negative transduction action at doses that do not affect coronary vasodilation.

Example 4

Distinguish between hypotensive and negative transmutational activity

Male Sprague-Dawley rats were anesthetized by intraperitoneal injection of 50 mg / kg of sodium pentobarbital, and an internal catheter was surgically implanted into the carotid and jugular vein two days before each experiment. During all subsequent experiments, rats were conscious and not restrained. The carotid cannula was attached to a pressure transducer and blood pressure was recorded throughout each experiment using a grass multipurpose recorder. The heart rate was derived from the blood pressure signal using the Grass Sok. The parameters measured were allowed to stabilize for 30-90 minutes before the test compound was administered.

Compound A was administered intravenously via an intravenous catheter or administered by oral gavage using a curved oral cannula for canal administration. Feed and water were made available at random.

The ED ₅₀ observed for bradycardia induction was 0.1 μg / kg / min in the vein for 120 minutes, which averaged 34% reduction in heart rate without changing the mean blood pressure. Intravenous dosage ranges from 0.05 μg / kg / min to 0.1 μg / kg / min have been shown to not change blood pressure. Similarly, the oral dosage range of 30 μg / kg to 100 μg / kg did not cause a change in blood pressure, and a dose of 100 μg / kg averaged 40% reduction in heart rate. This demonstrates that in the case of exemplary compounds a very pronounced negative variable effect is evident at doses that do not affect blood pressure.

Example 5

Demonstration of Negative Translocation and Negative Transcriptive Activity in Spontaneous Heart Rate

Hearts isolated from guinea pigs were prepared according to Langendorff's method, and the coronary vessels were perfused in a retrograde manner through the aorta at constant pressure. Compound A was administered to the spontaneously pulsating heart by injecting Compound A into the perfusion line supplying buffer to the coronary vasculature. The concentration of Compound A was adjusted by changing the infusion rate and / or changing the concentration of the infusion solution. The concentration of Compound A present in the perfusate was calculated by dividing the infusion rate of Compound A by the coronary flow rate. The spontaneous heart rate and AV interval were recorded.

The results of this experiment are shown in FIG. Compound A reduced AV conduction in a concentration dependent manner, with a maximum increase in AV interval of 34% above the default value. Compound A also reduced heart rate concentration dependently, EC ₅₀ value was 3.2 nM and maximum reduction in heart rate was 58%.

Example 6

Demonstrate the effect of heart rate on voice substation activity

Hearts isolated from guinea pigs were prepared according to the method described in Example 5. In Part 1 of the experiment, designed to measure the effect of heart rate on the negative transduction activity of Compound A, the heart is spontaneously beating, or 200 beats per minute (about 20% faster than spontaneous rate) or 300-360 per minute. It was electrically beating at a beat rate (approximately 80% faster than spontaneous speed).

Atrioventricular (AV) conduction interval (AV interval) was measured as the time from atrial stimulation to onset of ventricular polarization. AV intervals were measured at each beat rate while increasing the concentration of Compound A as described in Example 5. Electrically beating at 200 beats per minute Compound A increased AV interval by a maximum of 58% at an average concentration of 3.9 nM and induced cardiac block at an average minimum concentration of 5.1 nM. Electrically pulsating at 300-360 beats per minute Compound A increased AV intervals by up to 20% at an average concentration of 1.45 nM and induced cardiac block at an average minimum concentration of 2.1 nM. These results are summarized in the table below and the results from spontaneous beating heart are included for comparison.

Heart rate (bpm) Average concentration (nM) of compound A required to cause maximum AV interval Average minimum concentration (nM) of compound A required to trigger a heart block Voluntary (about 170) 11.7 13 200 3.9 5.1 300-360 1.45 2.1

The data demonstrate that the negative transduction effect caused by the exemplary compound is rate dependent and that the efficacy of Compound A increases as the rate of pulsation increases.

Example 7

Demonstration of Negative Transformer Activity in Experimental Models of Paroxysmal Ventricular Lesions

Using the experimental conditions described in Example 6, the individual hearts were beated at 200 bpm for 1 minute and then suddenly beated at 300 bpm for 1 minute, after which the beat rate was reduced to 200 bpm again. The 300 bpm beat cycle was to mimic paroxysmal ventricular tachycardia. This beat sequence was performed with increasing concentration of Compound A in the presence of excipients. This result is shown in FIG. Compound A with an average concentration of 2 nM with little effect on AV interval at 200 bpm induced AV blocks within 30 seconds during 300 bpm vacancy. Upon returning the beat rate to 200 bpm, the AV interval returned to normal.

Example 8

Distinction between Coronary Vasodilation and Negative Persistence Activity in the Beating Heart

To determine the difference in the efficacy of Compound A on negative variable activity versus coronary vasodilation in the pulsatile heart, a different set of experiments were conducted in which individual hearts were used to collect measurements for each action. The experimental conditions described in Example 6 were used and the hearts isolated from guinea pigs were beaten at 300-360 beats per minute. AV conduction spacing was measured as described in Example 6. Coronary perfusion flow data was determined by measuring the volume of fluid exiting the heart. AV conduction interval data and coronary perfusion flow data were collected with increasing concentration of Compound A. This result is shown in FIG. 3, where both the AV conduction interval and coronary perfusion flow increased in a dose dependent manner. The difference in these effects was easily identified. The average concentration of Compound A that maximized the AV conduction time was 0.76 nM. The concentration of Compound A (EC ₅₀ ) causing half of the maximum effect on coronary perfusion flow was 32 nM. Compound A has a 40 times more potent effect on reducing AV conduction time than increasing coronary perfusion flow.

The present invention has been sufficiently described, and it will be apparent to those skilled in the art that the present invention may be practiced within various and equivalent ranges of conditions, compositions and other parameters without affecting the scope or any embodiment of the present invention. . All patents, patent applications, and publications cited herein are incorporated herein in their entirety.

Claims (44)

A compound of formula (I) or a pharmaceutically acceptable salt or ester thereof, in the manufacture of a medicament for the treatment of cardiac rhythm disturbance in a mammal that would benefit from negative metabolic action, negative metabolic action, or induction thereof Uses for: Formula I Wherein R ₁ is C _3-7 secondary alkyl or C _3-8 cycloalkyl and R ₂ is C _1-4 alkyl or C _3-5 cycloalkyl. 2. Use according to claim 1, wherein R ₁ is 3-pentyl, cyclopentyl or norbornyl and R ₂ is methyl, ethyl, isopropyl or cyclopropyl. 2. Use according to claim 1, wherein the medicament is in a parenteral formulation. 4. Use according to claim 3, wherein the medicament is present in an intravenous formulation. Use according to claim 1, characterized in that the medicament is in oral dosage form. 2. Use according to claim 1, wherein R ₂ is ethyl. Use according to claim 1, characterized in that R ₂ is cyclopropyl. 2. Use according to claim 1, wherein R ₁ is 3-pentyl. 2. Use according to claim 1, wherein R ₁ is cyclopentyl. 10. Use according to claim 9, wherein R ₂ is ethyl. Use according to claim 9, characterized in that R ₂ is cyclopropyl. The compound of claim 4, wherein the compound is N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine, N ⁶ -cyclopentyl-5 '-(N-cyclopropyl) carboxamidoadenosine, N ^6- (3-pentyl) -5 '-(N-ethyl) carboxamidoadenosine, N ⁶ -cyclopentyl-5 '-(N-methyl) carboxamidoadenosine, and N ⁶ -cyclopentyl-5 '-(Nt-butyl) carboxamidoadenosine, Pharmaceutically acceptable salts and esters thereof Use characterized in that it is selected from the group consisting of. 5. Use according to claim 4, wherein the compound is N ^6- (3-pentyl) -5 '-(N-ethyl) carboxamidoadenosine. 4. Use according to claim 3, wherein the compound is N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine. 4. Use according to claim 3, wherein the compound is N ⁶ -cyclopentyl-5 '-(N-cyclopropyl) carboxamidoadenosine. 6. Use according to claim 5, characterized in that the compound is N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine. 6. The use according to claim 5, wherein the compound is N ⁶ -cyclopentyl-5 '-(N-cyclopropyl) carboxamidoadenosine. The method of claim 1, wherein the cardiac rhythm disturbance is a ventricular tachycardia. Use according to claim 1, characterized in that the cardiac rhythm disturbance is paroxysmal ventricular tachycardia. Use according to claim 1, wherein the cardiac rhythm disturbance is atrial fibrillation. An effective amount of a compound of formula (I) or a pharmaceutically acceptable salt or ester thereof is administered to a mammal in need of treatment of cardiac rhythm disturbances, Methods of treating heart rhythm disturbances in mammals that benefit from: Formula I Wherein R ₁ is C _3-7 secondary alkyl or C _3-8 cycloalkyl and R ₂ is C _1-4 alkyl or C _3-5 cycloalkyl. The method of claim 21, wherein R ₁ is 3-pentyl, cyclopentyl or norbornyl, and R ₂ is methyl, ethyl, isopropyl or cyclopropyl. The method of claim 21, wherein the compound is administered in a parenteral formulation. The method of claim 23, wherein the compound is injected intravenously. The method of claim 21, wherein the compound is administered in an oral dosage form. The method of claim 21, wherein R ₂ is ethyl. The method of claim 21, wherein R ₂ is cyclopropyl. The method of claim 21, wherein R ₁ is 3-pentyl. The method of claim 21, wherein R ₁ is cyclopentyl. The method of claim 29, wherein R ₂ is ethyl. The method of claim 29, wherein R ₂ is cyclopropyl. The compound of claim 24, wherein the compound is N ⁶ -cyclopentyl-5 '-(N-ethyl) carboxamidoadenosine, N ⁶ -cyclopentyl-5 '-(N-cyclopropyl) carboxamidoadenosine, N ^6- (3-pentyl) -5 '-(N-ethyl) carboxamidoadenosine, N ⁶ -cyclopentyl-5 '-(N-methyl) carboxamidoadenosine, and N ⁶ -cyclopentyl-5 '-(Nt-butyl) carboxamidoadenosine, Pharmaceutically acceptable salts and esters thereof Method characterized in that it is selected from the group consisting of. The method of claim 24, wherein the compound is N ^6- (3-pentyl) -5 '-(N-ethyl) carboxamidoadenosine. The method of claim 23, wherein the compound is N ⁶ -cyclopentyl-5 ′-(N-ethyl) carboxamidoadenosine. The method of claim 23, wherein the compound is N ⁶ -cyclopentyl-5 ′-(N-cyclopropyl) carboxamidoadenosine. The method of claim 25, wherein the compound is N ⁶ -cyclopentyl-5 ′-(N-ethyl) carboxamidoadenosine. The method of claim 25, wherein the compound is N ⁶ -cyclopentyl-5 ′-(N-cyclopropyl) carboxamidoadenosine. The method of claim 21, wherein the cardiac rhythm disturbance is ventricular tachycardia. The method of claim 21, wherein the cardiac rhythm disturbance is paroxysmal ventricular tachycardia. 22. The method of claim 21, wherein the cardiac rhythm disturbance is atrial fibrillation. A pharmaceutical composition in unit dosage form consisting of one or more active ingredients and one or more pharmaceutically acceptable excipients, wherein the amount is effective in the treatment or prevention of cardiac rhythm disturbances in a mammal administered at least one unit dosage. A pharmaceutical composition characterized by a compound of or a pharmaceutically acceptable salt or ester thereof: Formula I Wherein R ₁ is C _3-7 secondary alkyl or C _3-8 cycloalkyl and R ₂ is C _1-4 alkyl or C _3-5 cycloalkyl. 42. The pharmaceutical composition of claim 41, wherein the cardiac rhythm disturbance benefits from negative metastatic action, negative variable action, or induction thereof. The pharmaceutical composition of claim 41, wherein the pharmaceutical composition is in orally administrable form and the amount is about 1 to about 50 μg / kg body weight. The pharmaceutical composition of claim 41, wherein the pharmaceutical composition is in an intravenous injectable form and the amount is about 0.1 to about 10 μg / kg / min.