WO2009054682A2

WO2009054682A2 - Prodrug of atrovastatin by cholesterol's synthesis inhibitors

Info

Publication number: WO2009054682A2
Application number: PCT/KR2008/006264
Authority: WO
Inventors: Jong Bae Yoon; Hwal Jong Lee; Seon Jeong Yoon; Jong Sung Park
Original assignee: Astech Co Ltd
Current assignee: Astech Co Ltd
Priority date: 2007-10-23
Filing date: 2008-10-23
Publication date: 2009-04-30
Anticipated expiration: 2010-04-23
Also published as: WO2009054682A3; KR100813666B1

Abstract

The present invention relates to atorvastatin prodrugs or pharmaceutically acceptable salts thereof. The compound of the present invention is hydrolyzed to atorvastatin in a body and allows atorvastatin to be maintained in a concentration effective in inhibiting the production of cholesterol for a long time. Further, the compound of the present invention can reduce side effects caused by an initial high concentration of atorvastatin in blood, thereby improving safety problems remarkably. Therefore, the compound of the present invention is effective in treating or preventing various diseases caused by excessive cholesterol such as hyperlipidemia, etc.

Description

[DESCRIPTION]

[Invention Title]

PRODRUG OF ATROVASTATIN BY CHOLESTEROL' S SYNTHESIS INHIBITORS

[Technical Field]

<i> The present invention relates to a prodrug of atorvastatin, [R- (R*,R*)]-2-(4-f luorophenyl)-β , δ -dihydroxy-5-(l-methylethyl)-3-phenyl-4- [(phenylamino)carbonyl]-lH-pyrrole-l-heptanoic acid, which is an inhibitor of cholesterol synthesis and a method of treating hyperlipidemia by the prodrug.

[Background Art]

<2> Atorvastatin is a substance which reduces the production of cholesterol. It was known in the art that atorvastatin inhibits 3-hydroxy-3- methylglutaryl-coenzyme A (HMG-CoA) which catalyzes the reduction of HMG-CoA to mevalonate, which is the initial rate-limiting step in the biosynthesis of cholesterol (Goodman and Gilman, The Pharmacological Basis of Therapeutics 841, MacMillan Publ. Co.: New York 7th ed. , 1985).

<3> A decrease in the cholesterol synthesis stimulates the activity of low-density lipoprotein (LDL) receptors, resulting in the reduction of the amount of LDL particles in blood. A decrease in the LDL concentration in blood can reduce the risk of coronary artery diseases (J.A.M.A. 1984. 251, 351-74). Currently, atorvastatin is available under the registered trade name of Lipitor in the form of calcium salt. The efficacy and the synthetic method of said material are disclosed in U.S. Patent No. 5,273,996. The general formula of atorvastatin is given below:

<4> <5> However, atorvastatin has side effects and the main side effect involves safety problems, which includes myalgia, reduction of muscle strength, muscle weakness, gait disturbance, muscle hardening such as numbness, etc. which is related to a rise in CPK. The adverse effect also includes rhabdomyolysis.

<6> The cause of said adverse effect includes the reduction of ubiquinone (CoQ) forming a part of oxidative phosphorylation pathway which produces ATP. The reduction of CoQ inhibits the function of muscle cells and raises the level of CPK in serum, which leads to cell disruption involving the release of myoglobin. It also makes a disorder in the penetration of CI cell membrane by a direct reaction.

<7> Myotoxicity is dose-dependent. In case that the amount of administration is raised, the myotoxicity is increased. When combined with drugs for the treatment of renal inadequacy or the other drugs for the treatment of hyperlipidemia such as fibrate-based preparation, nicotinic acid preparation, etc., or combined with cyclosporine (immune-suppressive drug), the risk of onset of rhabdomyolysis increases.

<8> As disclosed above, atorvastatin inhibits 3-hydroxy-3-methylglutary- coenzyme A (HMG-CoA) which catalyzes the reduction of HMG-CoA to mevalonate in the synthesis of cholesterol, thereby reducing the level of cholesterol in blood. However, mevalonate is used as a basic substance for the synthesis of essential components in a body as well as cholesterol. Cholesterol is also an essential component in a body and a basic substance for the synthesis of hormone and the like. Thus, excessive inhibition of the production of mevalonate induces various side effects.

<9> Although atorvastatin is a superior therapeutic drug which controls the level of cholesterol in blood, since cholesterol is a precursor for the preparation of steroid hormone, bile acid, etc. and also an essential component for the constitution of cell membrane, cholesterol should be maintained at a certain level. If the concentration of cholesterol is lowered below optimal level, it brings side effects by lack of essential components in a body.

<io> Therefore, there is a need to develop new drugs that inhibit the synthesis of superfluous cholesterol, thereby treating various diseases caused by excessive cholesterol, while solving the above problem. [Disclosure] [Technical Problem]

<π> The present invention can provide a method of improving an availability of atorvastatin and effectively controlling the level of cholesterol by the use of atorvastatin prodrugs represented by the formula 1 which are degraded by an enzyme in a body to slowly release atorvastatin, thereby lessening the intensive accumulation of atorvastatin at an early stage and maintaining a constant level of atorvastatin in blood. [Technical Solution]

<i2> The present invention relates to atorvastatin prodrugs of the formula 1 and pharmaceutically acceptable salts thereof: <i3> Formula 1

<14>

<i5> wherein M represents H or metal salts, preferably Na, K, or Ca, more preferably Na or K, most preferably K.

<i6> The compound of the formula 1 is converted to atorvastatin by a degradation enzyme in a body. Specifically, the compound of the formula 1 is hydrolyzed to atorvastatin and atorvastatin lacton which is in turn hydrolyzed to atorvastatin. According to the stepwise hydrolysis, at an early stage of administration of the compound of the formula I, the content of atorvastatin in blood is relatively low. Further, since atorvastatin can be produced through the degradation of atorvastatin lacton, even though long time lapses after the administration of the compound of the formula I, the desired concentration of atorvastatin can be maintained, and thus the compound of the present invention shows a superior long acting feature.

<17> Compared with a direct administration of atorvastatin, the use of the compound of the present invention lessens the intensive accumulation of drugs at an early stage and maintains a constant level of drugs in blood, thereby improving the availability of atorvastatin and effectively controlling the level of cholesterol. Furthermore, the side effects caused by an initial high concentration of atorvastatin can be considerably lowered, which remarkably improves safety problem. Accordingly, the compound of the formula 1 according to the present invention can be used for the treatment or prevention of various diseases which are caused by excessive cholesterol such as hyper lipidemia, etc.

<i8> The compound of the formula 1 according to the present invention can be prepared by known techniques and the preparation methods are not limited to specific ones. For example, as shown in Reaction Scheme 1, the compound of the present invention can be prepared by reacting atorvastatin metal salt with acetate having a protecting and a leaving group in a reaction inert solvent .

<19> The term "reaction inert solvent" or "inert solvent" used herein refers to a solvent or a solvent mixture which does not adversely interact with starting materials, reagents, intermediates or products in the preparation of desired products. Particularly, N,N-dimethylformamide is a preferred solvent.

<20> Reaction Scheme 1

<21> <22> wherein M is as defined in the above, X represents leaving groups such as I, Br, Cl, para-toluenesulfonyl , methansulfonyl , etc., and R represents protecting groups such as tetrahydropyranyl , tetrahydrofuranyl , etc.

<23> The proper reaction temperature is O to 80° C, preferably room temperature. The acetate having a leaving and a protecting groups indicates the compound which has the leaving group of X such as I, Br, Cl, etc. and the protecting group of R such as tetrahydropyranyl, tetrahydrofuranyl, etc. The leaving group of X is preferably I or Br, particularly Br. The protecting group of R is preferably tetrahydropyranyl.

<24> The above method is described only for the purpose of illustration and the other various methods are possible, all of which are within the scope of the present invention.

<25> In another aspect, the present invention provides a pharmaceutical composition and preparation which comprises (a) a therapeutically effective amount of the compound of the formula 1 and (b) pharmaceutically acceptable carriers, diluents or excipients, or the combination thereof.

<26> As discussed above, the pharmaceutical composition of the present invention slowly releases atorvastatin degraded by an enzyme in a body, and thus lessen the intensive accumulation of atorvastatin at an early stage and maintains a constant level of atorvastatin in blood, thereby improving the availability of atorvastatin and effectively controlling the level of cholesterol. Therefore, the pharmaceutical composition of the present invention can be used for the treatment and/or prevention of the diseases selected from the group consisting of hyper lipidemia, hypercholesterolemia, benign prostatic hyperplasia, osteoporosis and Alzheimer.

<27> In a further aspect, the present invention provides a method of treating a mammal suffering from hyper lipidemia which comprises administering the compound of the formula 1 or a pharmaceutically acceptable salt thereof to said mammal .

<28> The term "pharmaceutical composition" used herein refers to a mixture of the compound of the present invention with other chemical components, such as diluents or carriers.

<29> The pharmaceutical composition facilitates administration of the compound to an organism. Multiple techniques of administering a compound exist in the art including, but not limited to, oral, injection, aerosol, parenteral, and topical administration. Pharmaceutical compositions can also be obtained by reacting the compound with inorganic or organic acids such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, p-toluenesulfonic acid, salicylic acid and the like.

<30> The term "a therapeutically effective amount" means an amount of the composition which ameliorates one or more symptoms of diseases treated by the composition. Thus, the therapeutically effective amount means an amount of the composition which (1) reverses the progression rate of diseases or (2) prevents the progression of diseases to some extent and/or (3) alleviates (preferably, reduces) one or more symptoms of diseases to some extent.

<3i> The term "carrier" defines a chemical compound that facilitates the incorporation of a compound into cells or tissues. For example dimethyl sulfoxide (DMSO) is a commonly utilized carrier as it facilitates the uptake of many organic compounds into the cells or tissues of an organism.

<32> The term "diluent" defines chemical compounds diluted in water that will dissolve the compound of interest as well as stabilize the biologically active form of the compound. Salts dissolved in buffered solutions are utilized as diluents in the art. One commonly used buffered solution is phosphate buffered saline because it mimics the salt conditions of human blood. Since buffer salts can control the pH of a solution at low concentrations, a buffered diluent rarely modifies the biological activity of a compound.

<33> The term "pharmaceutically acceptable" defines a carrier or diluent that does not abrogate the biological activity and properties of the compound.

<34> The pharmaceutical compositions described herein can be administered to a human patient per se, or in pharmaceutical compositions where they are mixed with other active ingredients, as in combination therapy, or suitable carriers or excipient(s) . Techniques for formulation and administration of the compounds of the instant application may be found in "Remington's Pharmaceutical Sciences," Mack Publishing Co., Easton, Pa., 18th edition, 1990.

<35> (1) Routes of Administration

<36> Suitable routes of administration may, for example, include oral, intranasal, transmucosal , or intestinal administration; parenteral delivery, including intramuscular, subcutaneous, intravenous, intramedullary injections, as well as intrathecal, direct intraventricular, intraperitoneal, or intraocular injections.

<37> Alternately, one may administer the compound in a local rather than systemic manner, for example, via injection of the compound directly into a O

solid tumor, often in a depot or sustained release formulation. Furthermore, one may administer the drug in a targeted drug delivery system, for example, in a liposome coated with tumor-specific antibody

<38> (2) Composition/Formulation

<39> The pharmaceutical compositions of the present invention may be manufactured in a manner that is itself known, e.g., by means of conventional mixing, dissolving, granulating, dragee-making, levigating, emulsifying, encapsulating, entrapping or lyophilizing processes.

<40> Pharmaceutical compositions for use in accordance with the present invention thus may be formulated in conventional manner using one or more pharmaceutically acceptable carriers comprising excipients and auxiliaries which facilitate processing of the active compounds into preparations which can be used pharmaceutically. Proper formulation is dependent upon the route of administration chosen. Any of the well-known techniques, carriers, and excipients may be used as suitable and as understood in the art; e.g., in Remington's Pharmaceutical Sciences, above.

<4i> For injection, the agents of the invention may be formulated in aqueous solutions, preferably in physiologically compatible buffers such as Hanks' s solution, Ringer's solution, or physiological saline buffer. For transmucosal administration, penetrants appropriate to the barrier to be permeated are used in the formulation. Such penetrants are generally known in the art .

<42> For oral administration, the compounds can be formulated readily by combining the active compounds with pharmaceutically acceptable carriers well known in the art. Such carriers enable the compounds of the invention to be formulated as tablets, pills, dragees, capsules, liquids, gels, syrups, slurries, suspensions and the like, for oral ingestion by a patient to be treated. Pharmaceutical preparations for oral use can be obtained by mixing one or more solid excipient with one or more compound of the invention, optionally grinding the resulting mixture, and processing the mixture of granules, after adding suitable auxiliaries, if desired, to obtain tablets or dragee cores. Suitable excipients are, in particular, fillers such as sugars, including lactose, sucrose, mannitol, or sorbitol; cellulose preparations such as, for example, maize starch, wheat starch, rice starch, potato starch, gelatin, gum tragacanth, methyl cellulose, hydroxypropylmethyl-cellulose, sodium carboxymethyl cellulose, and/or polyvinylpyrrolidone (PVP). If desired, disintegrating agents may be added, such as the cross-linked polyvinyl pyrrol idone, agar, or alginic acid or a salt thereof such as sodium alginate.

<43> Dragee cores are provided with suitable coatings. For this purpose, concentrated sugar solutions may be used, which may optionally contain gum arabic, talc, polyvinyl pyrrol idone, carbopol gel, polyethylene glycol, and/or titanium dioxide, lacquer solutions, and suitable organic solvents or solvent mixtures. Dyestuffs or pigments may be added to the tablets or dragee coatings for identification or to characterize different combinations of active compound doses.

<44> Pharmaceutical preparations which can be used orally include push-fit capsules made of gelatin, as well as soft, sealed capsules made of gelatin and a plasticizer, such as glycerol or sorbitol. The push-fit capsules can contain the active ingredients in admixture with filler such as lactose, binders such as starches, and/or lubricants such as talc or magnesium stearate and, optionally, stabilizers. In soft capsules, the active compounds may be dissolved or suspended in suitable liquids, such as fatty oils, liquid paraffin, or liquid polyethylene glycols. In addition, stabilizers may be added. All formulations for oral administration should be in dosages suitable for such administration.

<45> For buccal administration, the compositions may take the form of tablets or lozenges formulated in conventional manner.

<46> For administration by inhalation, the compounds for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebuliser, with the use of a suitable propel lant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. Capsules and cartridges of, e.g., gelatin for use in an inhaler or insufflator may be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch.

<47> The compounds may be formulated for parenteral administration by injection, e.g., by bolus injection or continuous infusion. Formulations for injection may be presented in unit dosage form, e.g., in ampoules or in multi-dose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents.

<48> Pharmaceutical formulations for parenteral administration include aqueous solutions of the active compounds in water-soluble form. Additionally, suspensions of the active compounds may be prepared as appropriate oily injection suspensions. Suitable lipophilic solvents or vehicles include fatty oils such as sesame oil, or synthetic fatty acid esters, such as ethyl oleate or triglycerides, or liposomes. Aqueous injection suspensions may contain substances which increase the viscosity of the suspension, such as sodium carboxymethyl cellulose, sorbitol, or dextran. Optionally, the suspension may also contain suitable stabilizers or agents which increase the solubility of the compounds to allow for the preparation of highly concentrated solutions.

<49> Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen-free water, before use.

<50> A pharmaceutical carrier for the hydrophobic compounds of the invention is a cosolvent system comprising benzyl alcohol, a nonpolar surfactant, a water-miscible organic polymer, and an aqueous phase. The cosolvent system may be the VPD co-solvent system. VPD is a solution of 3% w/v benzyl alcohol, 8% w/v of the nonpolar surfactant Polysorbate 80TM, and 65% w/v polyethylene glycol 300, made up to volume in absolute ethanol. The VPD co-solvent system (VPD:D5W) consists of VPD diluted 1:1 with a 5% dextrose in water solution. This co-solvent system dissolves hydrophobic compounds well, and itself produces low toxicity upon systemic administration. Naturally, the proportions of a co-solvent system may be varied considerably without destroying its solubility and toxicity characteristics. Furthermore, the identity of the co-solvent components may be varied: for example, other low-toxicity nonpolar surfactants may be used instead of Polysorbate 80TM; the fraction size of polyethylene glycol may be varied; other biocompatible polymers may replace polyethylene glycol, e.g., polyvinyl pyrrol idone; and other sugars or polysaccharides may substitute for dextrose.

<5i> Alternatively, other delivery systems for hydrophobic pharmaceutical compounds may be employed. Liposomes and emulsions are well known examples of delivery vehicles or carriers for hydrophobic drugs. Certain organic solvents such as dimethylsulfoxide also may be employed, although usually at the cost of greater toxicity.

<52> Additionally, the compounds may be delivered using a sustained-release system, such as semipermeable matrices of solid hydrophobic polymers containing the therapeutic agent. Various sustained-release materials have been established and are well known by those skilled in the art. Sustained- release capsules may, depending on their chemical nature, release the compounds for a few weeks up to over 100 days. Depending on the chemical nature and the biological stability of the therapeutic reagent, additional strategies for protein stabilization may be employed.

<53> (3) Effective Dosage.

<54> Pharmaceutical compositions suitable for use in the present invention include compositions where the active ingredients are contained in an amount effective to achieve its intended purpose. More specifically, a therapeutically effective amount means an amount of compound effective to prevent, alleviate or ameliorate symptoms of disease or prolong the survival of the subject being treated. Determination of a therapeutically effective amount is well within the capability of those skilled in the art, especially in light of the detailed disclosure provided herein.

-Lo

[Advantageous Effects]

<56> The compound of the formula 1 according to the present invention can reduce the side effects which are caused by an initial high concentration of atorvastatin when atorvastatin calcium is directly administered. As a result, the safety problems of atorvastatin can be remarkably improved. Therefore, the pharmaceutical composition which comprises the compound of the formula 1 as an effective component can be used for the treatment or prevention of various diseases caused by excessive hypercholesterol such as hyperlipidemia, etc. [Description of Drawings]

<57> Further objects and advantages of the invention can be more fully understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

<58> FIG. 1 is a graph showing the result of hydrolysis of the compound prepared in Example 2 by the enzyme in blood from rat;

<59> FIG. 2 is a graph showing the half life of the compound wherein the result of hydrolysis shown in FIG. 1 is converted by a log function;

<60> FIG. 3 is a graph showing the result of pharmacokinetic test of commercially available atorvastatin (LipitorTM);

<6i> FIG. 4 is a graph showing the result of pharmacokinetic test of the compound prepared in Example 2, according to Experimental Example 2;

<62> FIG. 5 is a graph showing the result of 13C NMR analysis of the compound prepared in Example 2; and

<63> FIG. 6 is a mass spectrum of the compound prepared in Example 2. [Mode for Invention]

<64> Hereinafter, the present invention will be explained in detail with reference to Preparative Examples and Experimental Examples. However, it is understood that the present invention is not limited to these specific embodiments.

<65>

<66> Preparat ion Example 1 : <67> [R-(R*,R*)]-2-(4-fluorophenyl)-β , δ -dihydroxy-5-(l-methylethyl )-3- phenyl-4-[(phenylamino)carbonyl]-lH-pyrrole-l-heptanoic acid potassium

<68> lOOg of atorvastatin lacton was dissolved to 1 L of acetone and 10.38g of potassium hydroxide dissolved in 100 mL of water was added thereto over 1 hour. The reaction solution was stirred for 8 hours at room temperature, the solvent was completely removed by a distillation under reduced pressure, and the residue was distilled under vacuum, suspended to 500 mL of acetone, and filtered. The filtrate was dried for 24 hours at a temperature of 60 ° C to obtain 95g pf atorvastatin potassium.

<69>

<70> Example 1:

<7i> [R-(R*,R*)]-2-(4-fluorophenyl)-β , δ -dihydroxy-5-(l-methylethyl)-3- phenyl-4-[(phenylamino)carbonyl]-lH-pyrrole-heptanoyloxy-acetic acid sodium

<72> 50 g of [R-(R*,R*)]-2-(4-fluorophenyl)-β , δ -dihydroxy-5-(l- methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-lH-ρyrrole-l-heptanoic acid potassium obtained in Preparation Example 1 was dissolved in 150 mL of N,N- dimethylformamide, 36g of tetrahydropyranyl bromoacetate was added thereto, and the mixture was stirred for 3 hours at room temperature. After adding 500 mL of water and 500 mL of ethylacetate to the reaction mixture and extracting the layer of ethylacetate, 700 mL of acetone and 700 mL of water were added. After completely dissolving them, pH was adjusted to 7 to 7.1, acetone was removed under vacuum distillation. The layer of water was twice extracted with 500 mL of solvent mixture of 1:1 of ethylacetate to hexane. The layer of water was completely removed under vacuum distillation. After adding 20 mL of water and 50 mL of acetone to the residue and completely dissolving the residue, the solution was stirred for 24 hours at a temperature of 5° C, resulting in the production of crystal. The obtained crystal was filtered, dried at a temperature of 60° C to obtain 23g of the title compound.

<73>

<74> Example 2 :

<75> [R-(R* ,R*) ]-2-(4-f luorophenyl )-β , δ -dihydroxy-5-( l-methyl ethyl )-3- phenyl-4-[(phenylaraino)carbonyl]-lH-pyrrole-heptanoyloxy-acetic acid calcium <76> 15g of [R-(R* ,R*)]-2-(4-fluorophenyl )-β , δ -dihydroxy-5-(l- methylethyl)-3-phenyl-4-[(phenylamino)carbonyl]-lH-pyrrole-heptanoyloxy- acetic acid sodium obtained in Example 1 was completely dissolved in 150 mL of water and 6g of calcium acetate dissolved in 60 mL of water was added thereto. After stirring the reaction mixture for 2 hours at room temperature and subsequently for 2 hours at a temperature of 0° C, the produced solid was filtered. The solid was recrystallized with a solvent mixture of 1:1 of ethylacetate to hexane and the crystal was filtered. After drying the crystal under vacuum for 12 hours at a temperature of 50° C, 12g of the title compound was obtained. 13C NMR analysis of the title compound is given in FIG. 5 and Mass spectrum is shown in FIG. 6.

<77>

<78> Experimental Example 1: Hydrolysis of the compound prepared in Example 2

<79> 5 mL of blood was taken from SD rats (7 to 8 weeks of age, about 25Og of weight) and lOOμl of the solution of the compound obtained in Example 2 (prepared by dissolving 4 mg of the compound obtained in Example 2 to 1 mL of acetonitril) was added to the blood, while maintaining the blood in a circulatory double boiler container at 37 ° C. After sampling 400 μl of the reaction liquid per hour, the liquid was diluted with ΘOOμl of acetonitril and centrifuged at 3,000 RPM for 3 minutes. The substance in the layer of acetonitril was taken and analyzed by HPLC. The analysis data is given in FIG. 1. As shown in FIG. 1, the compound prepared in Example 2 according to the present invention was hydrolyzed into two kinds of substances, that is, atorvastatin and atorvastatin lacton wherein the atorvastatin lacton was in turn hydrolyzed into atorvastatin, resulting in the production of atorvastatin in blood. FIG. 2 shows the half life of the compound converted to the final product of atorvastatin. According to FIG. 2, the half life of the compound prepared in Example 2 according to the present invention was 120 minutes. <80>

<81> Experimental Example 2: Pharmacokinetic analysis <82> The pharmacokinetic test of the compound prepared in Example 2 according to the present invention and a commercially available atorvastatin calcium (Lipitor TM) was practiced.

<83> SD rat (7 to 8 weeks of age, about 25Og of weight) was anesthetized by ketamine/xylazine and PE tube was inserted into a tail vein. The prepared drug was orally administered in an amount of 10 mg/2 mL/kg. Immediately before administration of the drug and 1, 2, 4, 6, 8, 10, and 24 hours after administration of the drug, about 0.3 mL of blood was collected, the blood was supplemented with an isotonic saline in which heparin was dissolved. After centrifuging the collected blood for 30 minutes at 3,000 rpm, plasma was obtained and maintained at a temperature of -20 ° C until the analysis of the plasma is carried out.

<84> To 100 μ 1 of plasma was added 1OmM phosphate potassium buffer (pH 7.4) and 10 μ 1 of internal standard liquid. After adding 800 μl of ethylacetate and mixing them for 1 minute, the mixture was centrifuged for 5 minutes at 13,000 rpm. The organic layer was taken and dried with a speed vacuum system. After dissolving in 50 μl of 80% acetonitril, the solution was injected to LC-MS/MS and analyzed. The result is given in Table 1.

<85> Table 1

<86>

<87> As shown in Table 1, the compound prepared in Example 2 according to the present invention showed AUC (area under the blood concentration vs. time curve) approximately 25% higher than the commercially available atorvastatin calcium, confirming that the compound of the present invention shows a superior bioavailability. Further, the Cmax (maximum concentration in blood) of the compound of the present invention was lower about ten times than the commercially available atorvastatin calcium. Since the initial concentration of atorvastatin in blood is not high, the side effect can be minimized.

<88> FIGs. 3 and 4 present the results of pharmacokinetic analysis of the commercially available atorvastatin calcium and the compound prepared in Example according to the present invention, respectively. As shown in the figures, most atorvastatin calcium is absorbed simultaneously with its administration, and a high concentration of atorvastatin in blood is maintained by 10 hours. Particularly, the atorvastatin calcium exhibited a high concentration of 0.1 to 0.01 for the initial 4 hours, but 12 hours after the administration, the sustained release of drug was considerably reduced (FIG. 3). However, the compound prepared in Example 2 according to the present invention maintained the level of atorvastatin which was converted from said compound to about 0.001 to 0.01 which belongs to the most proper range of atorvastatin which does not inhibit the synthesis of cholesterol, until 24 hours after administration of said compound lapse, without large fluctuation of the concentration of atorvastatin in blood over time (FIG. 4).

<89> Accordingly, it is understood that administration of the compound of the present invention allow atorvastatin to be maintained in a desired concentration in blood without large fluctuation for a long time. Therefore, it is expected that the side effect caused by an initial high concentration of atorvastatin can be remarkably reduced.

Claims

[CLAIMS] [Claim 1]

<91> A compound of the formula 1 and a pharmaceutically acceptable salt thereof:

<92> Formula 1

<93> <94> wherein M is H or a metal salt selected from the group consisting of Na, K, and Ca. [Claim 2]

<95> The compound of claim 1, wherein M is selected from the group consisting of H, Na, K, and Ca. [Claim 3]

<96> A pharmaceutical composition for treating and/or preventing the diseases selected from the group consisting of treatment hyperlipidemia, hypercholesterolemia, benign prostatic hyperplasia, osteoporosis and Alzheimer, which comprises (a) a pharmacologically effect amount of the compound of the formula 1 according to claim 1 and (b) pharmaceutically acceptable carriers, diluents or excipients, or the combination thereof. [Claim 4]

<97> The pharmaceutical composition of claim 3, wherein the composition is used for treating and/or preventing the diseases selected from the group consisting of treatment hyper lipidemia, hypercholesterolemia, benign prostatic hyperplasia, osteoporosis and Alzheimer. [Claim 5]

<98> A method of treating a mammal except for a human suffering from hyperlipidemia, which comprises administering the compound of the formula 1 according to claim 1 or a pharmaceutically acceptable salt thereof to said mammal .