EA042271B1 - METHOD OF TREATMENT USING A HETEROCYCLIC DERIVATIVE COMPOUND - Google Patents

Description

Technical field

The present invention relates to a method for treating or preventing hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis, or a disease associated with uric acid selected from the group consisting of hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction , cerebrovascular disease, diabetes and hypertension, comprising oral administration once a day to a person in need as an active ingredient of the compound of the following formula I or its pharmaceutically acceptable salt or their hydrate in a human dose of more than 2 to 10 mg or less, based on the weight of the free base of the compound of formula I:

O

I

State of the art

Agents currently used to treat or prevent hyperuricemia and gout include benzbromarone, which is a uric acid excretion agent with urate anion transporter 1 (hURAT1) inhibitory activity, as well as probenecid and sulfinpyrazone. However, these drugs do not have sufficient activity against URAT1. In particular, benzbromarone has some drawbacks in terms of adverse effects. Benzbromarone exhibits a pronounced inhibitory function for the 2C9 protein among the cytochrome P450 (CYP450) family proteins and thus has the potential for drug-drug interaction. The formation of reactive metabolites in glutathione (GSH) conjugate experiments has also been described [Dermot F. McGinnity et al., Drug Metabolism and Disposition, 33, p. 1700-1707 (2005)].

Moreover, since benzbromarone has a benzofuran backbone similar to the structures of the drugs benziodarone, benzarone and amiodarone, which are drugs that have been shown to have hepatotoxicity, it has the problem of causing death due to the induction of hepatotoxicity as well as the adverse effect of liver damage. . Thus, the liver function of patients who intend to prescribe this drug must be examined before administration, and even during administration during therapy, it is recommended to check for a certain period (six months) whether hepatotoxicity is induced or not. Thus, the field of medicine requires a drug that solves these problems [Hautekeete M.L., et al., Liver, 15, p. 25-29 (1995); Makoto Arai, et al., Journal of Gastroenterology and Hepatology, 17, p. 625-626 (2002); Saitama Medical College Magazine, 30, p. 187-194 (2003); Priska Kaufmann, et al., HEPATOLOGY, 41, p. 925-935 (2005)].

PCT Publication No. WO 2009/145456 (C&C Research Laboratories) describes heterocyclic derivative compounds having the following formula I, a specific example of which is (3,5-dibromo-4-hydroxyphenyl)-(2,3-dihydro-4H-pyrido [4,3-b][1,4]oxazin-4-yl)methanone (compound 4):

Formula I

PCT Publication No. WO 2009/145456 describes that the above compounds of heterocyclic derivatives show a pronounced inhibitory activity against human uratanion transporter 1 (hURAT1) compared to conventional inhibitors of hURAT1 activity, and thus they are useful as inhibitors, in in particular selective uric acid reuptake inhibitors. It also describes that the compounds do not exhibit cytochrome P450 (CYP450) drug-drug interactions, exhibit selectivity between organic anion transporters, have high solubility and metabolic stability, thereby exhibiting advantageous pharmacokinetics, and thus exhibit excellent effect compared with traditional drugs for the treatment or prevention of hyperuricemia, acute gouty arthritis, chronic gouty arthritis, tophus (gouty node), gouty nephrosis, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis and complications, which are reportedly accompanied by an increase blood uric acid levels such as hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction, cerebrovascular disease, diabetes and hypertension.

- 1 042271

The above document describes an experiment in which the heterocyclic derivative compounds described above were orally administered to Cebus monkeys at a dose of 3.75, 7.5 and 15 mg/kg. When these doses were theoretically converted to a dose that is applicable to humans, it reached about 15 to 60 mg, and at such high doses the risk of side effects is significant.

In addition, in the case of the hydrochlorides of the heterocyclic derivatives described above, due to their hygroscopic property, there are limitations in formulating them for oral administration by the wet granulation method.

In addition, as a method for synthesizing compounds of heterocyclic derivatives, the above document also describes a method for producing compounds of heterocyclic derivatives of formula I, including the steps of (1) halogenating a compound of formula VII, below, to obtain a compound of formula X, below, and then reacting the obtained compound of formula X with a compound of formula IX, below, to give a compound of formula VIII below, or alternatively, carrying out a Mitsunobu reaction between a compound of formula VII and a compound of formula IX to give a compound of formula VIII; (2) cyclization of the resulting compound of formula VIII to obtain a compound of formula IV, below; and (3) performing a peptide coupling reaction between the resulting compound of formula IV and a compound of formula III, below:

l'

Ry^ OH R*

[Formula VH]

Ri

Rj _χ ^m °g

R*

[Formula VII]

Ri

Rj _x

Rn

R* [Form X]

HOXX'R _1D

[Formula IX] ^Rr X% ^R 1O

Rs Rs

[Formula IX]

Ri

R ₂ NOi

JXXo

Λ ¹ XX .'J..

From' *s Rio

R ₆ R

[Formula Vlllj

[Formula VS] [Formula IV] [Formula Π]

However, among the oxazine derivatives of the above formula IV obtained as an intermediate in the above preparation method, the 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine derivative having the following structure is liquid and unstable, and its degradation causes the problem of the formation of impurities that can be carcinogenic or mutagenic. Since an additional purification process is required to remove these impurities, the production method described above is unsuitable for large-scale production.

Moreover, 3,5-dibromo-4-methoxybenzoyl chloride having the following structure, which is a compound of the above formula III in the above production method, is obtained from an expensive starting material of 3,5-dibromo-4-methoxybenzoic acid. In addition, a method for synthesizing a compound of formula III using an oxazine derivative of formula IV may introduce a genetic mutation, and thus a method capable of minimizing this possibility is required.

US Patent Publication No. US 2007-0010670 A1 (Japan Tobacco Inc.) describes an oxazine derivative compound of the following formula effective for treating hyperuricemia, gout, and the like, and a method for synthesizing the same:

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Description of the invention

Problem to be solved.

The present invention relates to a method for treating or preventing hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis, or a disease associated with uric acid selected from the group consisting of hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction , cerebrovascular disease, diabetes and hypertension, comprising oral administration once a day to a person in need as an active ingredient of the compound of the following formula I or its pharmaceutically acceptable salt or their hydrate in a human dose of more than 2 to 10 mg or less based on the weight of the free base of the compound of formula I.

Technical solution to the problem.

The present invention relates to a method for treating or preventing hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis, or a disease associated with uric acid selected from the group consisting of hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction , cerebrovascular disease, diabetes and hypertension, comprising oral administration once a day to a person in need as an active ingredient of the compound of the following formula I or its pharmaceutically acceptable salt or their hydrate in a human dose of more than 2 to 10 mg or less, based on the weight of the free base of the compound of formula I:

I

In one embodiment of the present invention, in the method of treatment described above, the human dose is 3 to 8 mg.

In another embodiment of the present invention, in the method described above, the active ingredient is the hydrochloride of a compound of formula I or its 1,5-hydrate (sesquihydrate).

Invention effect.

The dosage regimen according to the present invention, in which the compound of formula I is administered orally once a day at a dose of more than 2 to 10 mg or less based on the weight of the free base, shows an excellent effect in the treatment or prevention of hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis, or a uric acid-associated disease selected from the group consisting of hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction, cerebrovascular disease, diabetes, and hypertension, and minimizes the likelihood of side effects.

Moreover, the prior hydrochloride of the compound of formula I had the problem of formulating it for oral administration by the wet granulation method due to its high hygroscopicity. The 1,5-hydrochloride hydrate of the compound of formula I according to the present invention solves this problem and exhibits a stability suitable for oral formulations (especially tablets).

Brief description of the drawings

In FIG. 1 shows the NMR data of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine, HBr salt (dihydrobromide, 2HBr) according to the present invention prepared according to Example 1.

In FIG. 2 shows the results of thermogravimetric analysis (TC)/differential thermal analysis (DTA) of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine, HBr salt (2HBr), in accordance with the present invention, obtained according to example 1.

In FIG. 3 shows NMR data for a compound of formula I according to the present invention prepared according to Example 2.

In FIG. 4 shows the results of an X-ray powder diffraction (XRD) analysis of the 1,5-hydrate hydrochloride of a compound of formula I according to the present invention prepared according to Example 3.

In FIG. 5 shows NMR data for 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine sulfate.

In FIG. 6 shows TG/DTA results for 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine sulfate.

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In FIG. 7 shows NMR data for the free base form of 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine.

In FIG. 8 shows TG/DTA results for the free base form of 3,4-dihydro-2HpyRido[4,3-b][1,4]oxazine.

In FIG. 9 shows the results of an X-ray powder diffraction (XRD) analysis of a non-solvate hydrochloride of a compound of formula I (a) and a 1,5-hydrate hydrochloride of a compound of formula I according to the present invention (b).

In FIG. 10 shows TG/DTA results for a non-solvate hydrochloride compound of formula I (a) and a 1,5-hydrate hydrochloride compound of formula I according to the present invention (b).

In FIG. 11 is a water absorption isotherm for a non-solvate hydrochloride of a compound of formula I (a) and a 1,5-hydrate hydrochloride of a compound of formula I according to the present invention (b).

In FIG. 12 shows the solubility of the 1,5-hydrate hydrochloride of a compound of formula I according to the present invention compared to a non-solvate hydrochloride of the same compound.

In FIG. 13 shows the percentage of patients whose serum uric acid level fell below <5.0 mg/dl (right column) and the percentage of patients whose serum uric acid level fell below <6.0 mg/dl (left column) , with the introduction of the compounds of formula I in accordance with the present invention in low doses (0.25, 0.5, 1 mg) and at a dose of 2 mg.

In FIG. 14 shows the percentage of patients whose serum uric acid level fell below <5.0 mg/dl (right column) and the percentage of patients whose serum uric acid level fell below <6.0 mg/dl (left column) at the introduction of the compounds of formula I in accordance with the present invention in doses within the stated dosing regimen (3, 5, 7, 10 mg).

Specific embodiments of the invention

Below, the present invention is explained in more detail.

Use of a compound of formula I.

The present invention relates to a method for treating or preventing hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis, or a disease associated with uric acid selected from the group consisting of hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction , cerebrovascular disease, diabetes and hypertension, comprising oral administration once a day to a person in need as an active ingredient of the compound of the following formula I or its pharmaceutically acceptable salt or their hydrate in a human dose of more than 2 to 10 mg or less, based on the weight of the free base of the compound of formula I:

O

I

In one embodiment of the present invention, in the method of treatment described above, the human dose is 3 to 8 mg.

In another embodiment of the present invention, in the method described above, the active ingredient is the hydrochloride of a compound of formula I or its 1,5-hydrate (sesquihydrate).

Pharmaceutically acceptable salts may include acid addition salts prepared using acids which form non-toxic acid addition salts containing pharmaceutically acceptable anions, for example inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, hydrobromic acid, hydroiodic acid, etc.; organic carboxylic acids such as tartaric acid, formic acid, citric acid, acetic acid, trichloroacetic acid or trifluoroacetic acid, gluconic acid, benzoic acid, lactic acid, fumaric acid, maleic acid, etc.; and sulfonic acids such as methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid or naphthalesulfonic acid. Also included are alkali metal salts such as sodium, potassium and the like. In addition, salts with other acids or bases which are known and commonly used in the art, relating to aromatic amidine derivatives or lactam derivatives, may also be included. Moreover, hydrate forms may include hemihydrate, monohydrate, 1.5-hydrate (sesquihydrate), dihydrate, trihydrate, and the like.

In particular, the pharmaceutically acceptable salt may be the hydrochloride and the hydrate may be the 1.5-hydrate.

Hyperuricemia is an abnormally high level of uric acid in the blood. It is defined as a condition in which the serum uric acid level is higher than normal (7-8 mg/dl for men, 6 mg/dl for women) due to decreased excretion of uric acid in the kidneys.

- 4 042271 or overproduction of uric acid in the liver. Gout has a significantly higher than normal (7-8 mg/dl for men, 6 mg/dl for women) blood uric acid levels due to overproduction of uric acid or decreased excretion of uric acid. Uric acid crystals can be deposited in connective soft tissues such as joints and ligaments, and needle-shaped uric acid crystals can prick (pierce) the muscles around joints. The body's immune system then attacks the uric acid crystals, which causes severe pain and swelling in the joints. Such paroxysmal and inflammatory forms of arthritis are called gout. Uric acid crystals are deposited mainly in the metatarsophalangeal joint of the thumb and rarely in the lumbar spine [Vervaeck M., et al., Clinical Neurology and Neurosurgery, 93, p. 233-236 (1991)].

Gout is a very dangerous factor because it can aggravate various metabolic diseases such as diabetes, hypertension, heart disease, obesity, nephrolithiasis, urolithiasis, and the like. The peak incidence of gout is observed mainly in men aged 40-50 years and an increase in the incidence is observed in postmenopausal women. Also, the frequency of occurrence is high in obese individuals and individuals who are intensively engaged in strength exercises.

The incidence of gouty attacks is closely associated with patients who have had hyperuricemia for several years. It has been described that the incidence of gouty attack is 4.9% when the body uric acid level is 9mg/dl or higher, 0.5% when the body uric acid level is 7.0~8.9mg/dl, and 0.1% when body uric acid levels are 7.0 mg/dl or below and the 5-year cumulative incidence of gouty attacks is approximately 22% in patients with body uric acid levels 9 mg/dl or above [Campion E.W. et al., Am. J. Med., 82, p. 421-426 (1987)].

A decrease in serum acid (UA) below <6.0 mg/dl, more preferably below <5.0 mg/dl is clinically relevant for the treatment of patients with severe gout. The dosage regimen according to the present invention, in which a compound of formula I or a pharmaceutically acceptable salt or hydrate thereof is orally administered once a day at a dose of more than 2 to 10 mg or less, based on the weight of the free base of the compound of formula I, has a significant effect to reduce the patient's serum uric acid level to <5.0 mg/dL.

In particular, as can be seen in Experimental Example 4 below, in the case of administration of 3, 5, 7, and 10 mg according to the dosage regimen of the present invention, the percentage of patients whose serum uric acid level fell below <5.0 mg/dl were approximately 23%, 64%, 80%, and 73%, respectively, in other words, ranged from approximately 23% to 80% (see FIG. 14). However, when the same compound was administered at the 0.25, 0.5, and 1 mg doses, there were no patients with serum uric acid levels below <5.0 mg/dL, and only at the 2 mg dose, this percentage was only approximately 8% ( see Fig. 13). From the above experimental results, it can be understood that a significant effect occurs at a dose of more than 2 mg, which is the lower limit of the dosage range in the dosing regimen in accordance with the present invention.

Moreover, the dosage regimen according to the present invention, in which the compound of formula I is administered orally once a day at a dose of more than 2 to 10 mg or less, shows a pronounced inhibitory activity against human urate anion transporter 1 (hURAT1), and thus it is useful for treating or preventing hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis or uric acid associated disease such as hyperlipidemia, coronary heart disease, myocardial infarction, cerebral infarction, cerebrovascular disease, diabetes, hypertension, and the like.

In one embodiment of the present invention, the dose of the compound of formula I may vary depending on the disease, condition, age, body weight of the patient and dosage form in the range from more than 2 to 10 mg or less, administered orally once a day. In particular, the compound can be administered orally once a day at a dose of 3 to 8 mg, and more particularly once a day at a dose of 3 to 6 mg. The range described above is based on the free base form of the compound of formula I which is the active ingredient, and the compound of formula I can be administered in the form of the hydrochloride or its 1.5-hydrate form. In particular, when a compound of formula I is administered in its hydrochloride 1,5-hydrate form, the dose may be from more than 2.3 to 11.5 mg or less.

At doses equal to or less than 2 mg, a sufficient effect was not demonstrated in relation to the treatment of the diseases mentioned above. At a dose of 10 mg, the maximum effect has already been demonstrated. In addition, while doses above 10 mg exhibit a uric acid concentration-lowering effect, such doses may induce arthralgia, joint swelling, and the like. during treatment, which may cause pain to the patient, and there is the possibility of other side effects. These side effects include elevated creatinine levels, which can cause fatal illness, especially in the kidneys. As can be seen in Experimental Example 5 described below, it can be concluded that when the dose exceeds 10 mg, which is the maximum dose of the dosing regimen of the present invention, there is a higher risk of adverse effects such as arthralgia and swelling occurring. joints, and an increased concentration of creatinine in the urine.

The subject for use in accordance with the present invention is an animal, preferably a mammal, most preferably a human.

Hereinafter, the present invention is explained in more detail by means of illustrative examples. However, the following illustrative examples are only intended to illustrate one or more embodiments and are not intended to limit the scope of the invention.

Examples

Example 1

Synthesis of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine, HBr salt (dihydrobromide, 2HBr), which is a compound of formula IV.

(1) Preparation of 4-chloro-3-nitropyridine.

g (0.356 mmol) of 4-hydroxynitropyridine was added to 50 ml (1 T) DMF (dimethylformamide) and 450 ml (9 T) ethyl acetate and stirred. 42.5 ml of phosphoryloxychloride (POCl ₃ , 1.3 eq.) was added and the mixture was heated and refluxed at 70-80°C for 2 hours. After completion of the reaction, the reaction solution was cooled to 40°C and 200 ml of water was added to complete the reaction. The separated organic layer was washed with 200 ml of saturated sodium bicarbonate (NaHCO ₃ ) and 200 ml of brine, respectively, and the collected organic layer was dried over magnesium sulfate (MgSO ₄ ), filtered, and concentrated under reduced pressure to obtain 60 g of concentrated 4-chloro-3- crystals. nitropyridine light yellow.

(2) Preparation of methyl 2-((3-nitropyridin-4-yl)oxy)acetate.

g (0.356 mmol) of 4-chloro-3-nitropyridine obtained in the above step (1) was dissolved in 300 ml (5 T) of DMF, 36 ml (1.3 eq.) of methyl glycolate and 74 g (1.5 equiv.) powdered potassium carbonate (K ₂ CO ₃ ) and the mixture was heated and reacted at 70-80°C for 1-2 hours. After completion of the reaction, the reaction mixture was cooled to room temperature, dissolved and neutralized by adding 150 ml of 10% HCl and extracted with 500 ml of ethyl acetate. The resulting organic layer was washed with 150 ml of brine, and the resulting organic layer was concentrated under reduced pressure and dried in vacuo to give 62 g (82%) of methyl 2-((3-nitropyridin-4-yl)oxy)acetate as a light brown solid.

(3) Preparation of 2H-pyrido[4,3-b][1,4]oxazin-3(4H)-one.

g (0.291 mmol) of methyl 2-((3-nitropyridin-4-yl)oxy)acetate obtained in the above step (2) was dissolved in 480 ml of acetonitrile (ACN) and 120 ml of water (H ₂ O) was added, 16 g (1.0 eq.) ammonium chloride (NH ₄ Cl) and 33 g (2.0 eq.) powdered iron (Fe) and the mixture was heated and reacted at 70-80°C for 2 hours. reaction mixture was cooled to room temperature, 30 ml of concentrated HCl was added and the mixture was stirred for 30 min. The reaction solution was filtered to remove insoluble matter. The resulting reaction solution was concentrated until a solid was obtained. The concentrate was added to methanol, stirred and filtered to give 2H-pyrido[4,3-b][1,4]oxazin-3(4H)-one hydrochloride. It was dissolved in water and then neutralized with 10% sodium hydroxide (NaOH) (pH 6-7), the resulting solid was filtered and dried to give 2H-pyrido[4,3-b][1,4]oxazine-3(4H )-she.

¹ H-NMR (300 MHz, MeOD-d): δ = 8.06 (m, 2H), 6.97 (s, 1H), 4.72 (s, 2H).

(4) Preparation of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine.

g (0.251 mmol) of 2H-pyrido[4,3-b][1,4]oxazin-3(4H)-one obtained in the above step (3) was dissolved in 570 ml of tetrahydrofuran (THF) (15 T) and the temperature of the reaction solution was cooled to 0°C. 15 g (1.5 equiv.) lithium aluminum hydride (LiAlH ₄ , LAH) was added several times and the reaction solution was warmed to room temperature and stirred for 2 h. ₂ O and the mixture was stirred for 10 minutes. 80 ml of 5% NaOH solution was added dropwise to the mixture, and the mixture was stirred for 30 min at room temperature. The reaction solution was filtered to remove insoluble substances Al(OH) ₃ . The filtrate was neutralized (pH 7) with 10% HCl, extracted with ethyl acetate, and the organic layer was washed with brine and dried over anhydrous sodium sulfate (Na ₂ SO ₄ ) and filtered. The filtrate was concentrated under reduced pressure to give 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine (30 g, 90%).

(5) Preparation of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine, HBr salt (2HBr), 100 g (0.666 mol) 2H-pyrido[4,3-b][ 1,4]oxazin-3(4H)-one was stirred in 570 ml.

THF (15 T) and the temperature of the reaction solution was lowered to 0°C. 38 g (0.999 mol, 1.5 eq.) of lithium aluminum hydride (LiAlH ₄ , LAH) were added several times and the reaction solution was warmed to room temperature and stirred for 2 h. After completion of the reaction, the reaction mixture was cooled and quenched at 0°C, filtered and concentrated, stirred with MS (methylene chloride) and filtered. The MS used in this reaction was 1000 ml solution (10 v/w) of 2H-pyrido[4,3-b][1,4]oxazin-3(4H)-one. To a solution of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine/MS was added bromic acid in 294 g (210 ml) of 33% acetic acid (d, 1.40 g/ml) , which corresponds to 6 042271 1.8 eq. (calculated as 2H-pyrido[4,3-b][1,4]oxazin-3(4H)-one, 1.199 mmol) dropwise at 20-30°C for 20-30 min. The resulting crystalline solution was stirred at room temperature for 1 hour, cooled to 5-10° C., and then stirred for an additional 30 minutes. The crystalline solution was filtered, washed with 300–500 ml of MC, and vacuum dried for 5 h at room temperature, reaching 95% yield of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine, salt HBr (2HBr), which is a compound of the following formula IV:

The NMR data of the compound described above are shown in FIG. 1 and the thermogravimetric (TG)/differential thermal analysis (DTA) results of said compound are presented in FIG. 2.

Example 2

Synthesis of (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone which is a compound of formula I.

l tetrahydrofuran (THF) was added to the reactor at 25-30°C, and then 139 g (0.470 mol) of 3,5-dibromo-4-hydroxybenzoic acid and 278 g (1.27 mol) of di-tert-butyl dicarbonate were added to the reactor . 125 g (1.58 mol) of pyridine was added under nitrogen atmosphere, and the reaction solution was stirred at 25-30° C. for 2 hours to obtain a reaction solution which contains 3,5-dibromo-4-tert-butoxycarbonyloxy-benzoic acid and (tert-butylcarbonyl) 3,5-dibromo-4-((tert-butoxycarbonyl)oxy)benzoic acid anhydride.

To the above reaction solution was added 170 g (1.68 mol) of triethylamine at a temperature of 25-30°C, and 100 g of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine was added thereto , salt of HBr (2HBr), obtained according to example 1. The reaction solution was stirred at 25-30°C for 6 hours. After removal of the formed salts (precipitate), the filtrate was collected and concentrated at a temperature of 25-30°C (2,6-dibromo-4-(1,2,3,4-tetrahydro-1,7-naphthyridine-1-carbonyl)phenyl)carbonate.

500 ml of isopropyl alcohol was added to the reactor at a temperature of 25-30°C which contained tert-butyl-(2,6-dibromo-4-(1,2,3,4-tetrahydro-1,7-naphthyridine-1-carbonyl) phenyl carbonate, and then 500 ml of concentrated hydrochloric acid was slowly added thereto at 45° C. or lower. The reaction solution was cooled to 25-30°C and stirred for 1-2 hours. 3 L of isopropyl alcohol was added to the reaction solution at 25-30°C and further stirred for an additional 1 hour, and then the reaction solution was cooled to 20-25 °C. The resulting crystals were filtered and dried to give (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin-4yl)methanone hydrochloride.

Water was added to the clean reactor, and (3,5-dibromo-4hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone hydrochloride was added to the reactor, obtained as described above at 25-30°C, and then the reaction solution was stirred at 25-30°C for 15 minutes. Slowly added 100 ml of 4N. an aqueous sodium hydroxide solution at 25-30° C. until the pH value reached 10.0, and the reaction solution was filtered and the filtrate was collected. Ethyl acetate was added to the reactor and stirred to separate the aqueous layer, and 10% aqueous hydrochloric acid was added at 20-25° C. until the pH reached 6.4 to 6.7. The resulting crystals were filtered to give (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone which is a compound of formula I (yield: 60%, purity: 98.0% or more). The NMR data of the compound described above are shown in FIG. 3.

Example 3

Synthesis of (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate.

g (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone obtained according to example 2 was placed in a reactor at 25° C. and 584 ml of acetic acid was added thereto at the same temperature, and 83 ml of water was added to the reactor. After 111 ml of 2 M aqueous hydrochloric acid was added to the reactor at 25°C, 688 ml of acetone was added to the reaction solution to form crystals, and the obtained crystals were filtered and dried in vacuum for 12 hours to obtain hydrochloride 1.5-hydrate (3.5 -dibromo-4-hydroxyphenyl)(2,3-dihydro-4Hpyrido[4,3-b][1,4]oxazin-4-yl)methanone (yield: 90%, purity: 99.9%).

Results of X-ray powder diffraction (XRD) analysis of the obtained (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazine hydrochloride 1,5-hydrate -4yl)methanone are shown in FIG. 4. As shown in FIG. 4, (3,5-Dibromo-4hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate shows characteristic peaks at the following 2θ positions (two-theta):

.89±0.5°, 10.84±0.5°, 11.48±0.5°, 13.73±0.5°, 15.85±0.5°, 17.61±0, 5°, 18.51±0.5°, 19.98±0.5°,

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21.42±0.5°, 22.99±0.5°, 23.27±0.5°, 24.11±0.5°, 24.76±0.5°, 27.37±0 .5°, 27.99±0.5°, 31.43±0.5°, 34.20±0.5°.

Experimental example 1.

Stability of 3,4-dihydro-2H-pyrido[4,3-b][1,4]oxazine, HBr salt (dihydrobromide, 2HBr).

Stability comparison experiments were carried out for 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine, HBr salt (2HBr), according to the present invention, prepared according to Example 1, and various salt forms prepared in the same way. 3,4-Dihydro-2H-pyrido[4,3b][1,4]oxazine phosphate was obtained in gel form and not in solid form. 3,4-Dihydro-2H-pyrido[4,3b][1,4]oxazine hydrochloride was also unstable in semi-solid form. Only 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine, HBr salt (2HBr), and 3,4-dihydro-2H-pyrido[4,3-b][1,4] sulfate ]oxazine was obtained in solid form.

As shown in Table. 1, in the case of the sulfate form, not only did the purity of the obtained material become lower compared to the free base form of 3,4-dihydro-2H-pyrido[4,3b][1,4]oxazine, but also a phenomenon occurred in the stability test when the solid melted back into liquid. In contrast, in the case of the HBr salt, not only did the purity increase relative to that in the free base form, but also the 4 week stability test showed no significant change from the original purity.

Table 1

Results of the stability comparison experiment

No. Type Initial purity Conditions 1 week 2 weeks 4 weeks Note 1 Free base 99.36% 3°C, 65%RH 97.72% 97.96% 98.18% > 97.5% 40°С, 75%RH 97.74% 97.91% 98.10% 2 Bromate 99.79% 3°C, 65%RH 99.89% 99.61% 99.58% stable 40°С, 75%RH 99.89% 99.61% 99.56% 3 Sulfate 98.88% 3°C, 65%RH 99.05% 99.85% Molten not stable 40°С, 75%RH Molten Molten Molten

In addition, the HBr salt form of the sulfate form and the free base form were determined using NMR, and thermogravimetric (TG) analysis and differential thermal analysis (DTA) were performed.

The NMR data for the HBr salt (2HBr) are shown in FIG. 1 and the thermogravimetric (TG) analysis/differential thermal analysis (DTA) results for it are shown in FIG. 2.

In addition, NMR data for sulfate are shown in FIG. 5 and the TG/DTA results for it are presented in FIG. 6.

In addition, NMR data for the free base are shown in FIG. 7 and the TG/DTA results for it are shown in FIG. 8.

Experimental example 2.

Stability of (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate.

For (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate according to the present invention prepared according to Example 3 and a non-solvate hydrochloride of the same compound were analyzed using powder X-ray diffraction (XRD), TG/DTA and measurement of the water sorption isotherm, and the results are shown in FIG. 9-11.

In particular, the results of analysis using powder X-ray diffraction (XRD) for non-solvate (a) and 1,5-hydrate (b) are shown in FIG. 9.

The TG/DTA results for non-solvate (a) and 1.5-hydrate (b) are shown in FIG. 10.

The water sorption isotherms for the non-solvate (a) and 1.5-hydrate (b) are shown in Figs. eleven.

In addition, a comparison was made of physical stability in relation to processing factors for the above-described 1.5-hydrate and non-solvate, and the results are presented in table. 2.

- 8 042271

table 2

Comparison of physical stability in relation to processing factors

Test conditions Grade after processing Form not solvate HC1 Form 1.5- HC1 hydrate Trituration* Change in crystallinity **** □ Δ8% (97^89%) Δ3% (94—>91%) Granulation with water ** solid form Mix with shape 1.5- HC1 hydrate Unmodified Granulation with water and ethanol 1:1 ** solid form Mix with shape 1.5- HC1 hydrate Unmodified Tableting* * * Change in crystallinity **** Δ8% (97^90%) Δ5% (94^89%)

* Mortar samples for approximately 2 min using the mortar.

** After adding 30% vol./wt. solvent samples were granulated for approximately 2 min using a mortar. After storing the granulated samples in closed vials for approximately 1 hour, the samples were dried at 50°C for approximately 3 hours.

*** Samples were pressed at a pressure of 2 tons for 5 seconds using 7 mm flat face punches.

**** Crystalline substances were evaluated using an X-ray powder diffractometer.

As shown in Table. 2, as a result of comparing the changes in crystallinity during grinding and tabletting, the 1,5-hydrate was significantly more stable than the non-solvate. In addition, as a result of comparison of solid forms upon granulation, it was observed that the non-solvate was partially converted to 1.5-hydrate, while the 1.5-hydrate showed no change. Thus, it was understood that the 1,5-hydrate exhibited better physical stability than the non-solvate.

Experimental example 3.

Solubility of (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4Hpyrido[4,3-b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate.

The solubility was compared between (3,5-dibromo-4hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate according to with the present invention prepared according to Example 3 and not the hydrochloride solvate of the same compound. The solubility test was carried out using 50 ml of FeSSIF (pH 5.0) as a medium and with a paddle speed of 50 rpm under operating conditions at 37°C. Solubility was determined using a physical mixture of 10 mg compound and 100 mg lactose as a sample. The results are shown in FIG. 12. After 240 minutes, the solubility of hydrochloride 1,5-hydrate was approximately 125 μg/ml, while the solubility of the non-solvate was reduced to approximately 112.5 μg/ml.

Experimental example 4.

Comparison of effects on dose of (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone.

(3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxαzin4-yl)methanone hydrochloride 1,5-hydrate according to the present invention, obtained according to example 3, was administered to a total of 60 patients with gout. The compound was administered orally at doses of 0.25 mg (N=12), 0.5 mg (N=12), 1 mg (N=12) and 2 mg (N=12) based on the weight of the active ingredient (3.5 -dibromo-4-hydroxyphenyl)(2,3dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone (formula I) and placebo (N=12), for 14 days . The efficacy and safety of the compound in relation to serum uric acid (UA) was evaluated in comparison to placebo.

Serum uric acid levels were quantified on day 15 post-administration and the percentages of patients whose serum uric acid levels fell to below <6.0 and below <5.0 mg/dL were determined and are shown in FIG. 13. As shown in FIG. 13, when the compound was administered at the 0.25, 0.5 and 1 mg doses, no patient showed a serum uric acid level below <5.0 mg/dl, and only at the 2 mg dose the percentage was only about 8%. From the results described above, it could be understood that a dose of less than 2 mg is not effective in the treatment of diseases such as hyperuricemia and gout.

In addition, (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-nirido[4,3b][1,4]oxazin-4-yl)methanone hydrochloride 1,5-hydrate according to the present invention was administered to a total of 68 patients with gout. The compound was orally administered at doses of 3 mg (N=13), 5 mg (N=14), 7 mg (N=15) and 10 mg (N=15) in

- 9 042271 based on the weight of the active ingredient (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone (formula I) and placebo (N=11) for 14 days. Compound was evaluated for efficacy and safety in relation to serum uric acid levels compared to placebo.

Serum uric acid levels were determined on day 15 post-administration and the percentages of patients whose serum uric acid levels dropped to below <6.0 and below <5.0 mg/dL were determined and are shown in FIG. 14. As shown in FIG. 14, for the 3, 5, 7, and 10 mg doses of the compound, the percentages of patients whose serum levels fell below <5.0 mg/dL were approximately 23%, 64%, 80%, and 73%, respectively, in other words, they ranged from about 23% to 80%. Patients whose serum uric acid levels fell below <6.0 mg/dl were also present in all experimental dose groups.

From the above experimental results, it can be understood that a significant effect occurs at a dose of more than 2 mg, which is the lower limit of the dosage range of the dosing regimen in accordance with the present invention.

Experimental example 5.

Review of side effects per dose of (3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3b][1,4]oxazin-4-yl)methanone.

(3,5-dibromo-4-hydroxyphenyl)(2,3-dihydro-4H-pyrido[4,3-b][1,4]oxazin4-yl)methanone hydrochloride 1,5-hydrate according to the present invention, obtained according to example 3, was administered to a total of 76 patients with gout. The compound was orally administered at doses of 3 mg (N=14), 5 mg (N=15), 7 mg (N=17) and 10 mg (N=17) based on the weight of the active ingredient (3,5-dibromo-4 -hydroxyphenyl)(2,3dihydro-4H-pyrido[4,3-b][1,4]oxazin-4-yl)methanone (formula I) and placebo (N=13) for 14 days and studied adverse reactions to it is a medicinal product. As a result, as shown in Table. 3 below, the dosing regimen described above showed no or very low incidence of adverse events such as arthralgia and joint swelling.

Table 3

Adverse drug reactions

Type Placebo (N=13) 3μγ(N=14) 5μγ(Ν=15) 7μγ(N=17) 10μγ(N=17) Arthralgia 0 0 0 0 2 persons (11.76%) [3 case] Joint swelling 0 0 0 0 1 person (5.88%) [1 case]

Moreover, urinary creatinine levels were also measured in the same patients. The number of cases where the creatinine level increased by more than 0.3 mg / dl, or more than 1.5 times compared with the baseline, is presented in table. 4.

Table 4

Number of times creatinine increased by more than 0.3 mg/dl or more than 1.5 times baseline

Dose Number of cases placebo 1 5 mg 1 10 mg 3

As shown in Table. 4, only one case was observed in the placebo group and in the 5 mg dose group, while three cases were observed in the 10 mg dose group, which is the maximum dose. From the above results, it can be concluded that the risk of increasing urinary creatinine concentration is higher when the dose exceeds the maximum dose of 10 mg.

Claims (3)

CLAIM 1. A method for treating or preventing hyperuricemia, gout, nephritis, chronic renal failure, nephrolithiasis, uremia, urolithiasis, or a disease associated with uric acid selected from the group consisting of hyperlipidemia, coronary heart disease, myocardial infarction, arteriosclerosis, cerebral infarction, cerebrovascular diseases, diabetes and hypertension, comprising oral administration once a day to a person in need as an active ingredient of the compound of the following formula I or its pharmaceutically acceptable salt or their hydrate in a human dose of more than 2 to 10 mg or less per calculation - 10 042271 units per weight of the free base of the compound of formula I: 2. The method of claim 1 wherein the human dose is 3 to 8 mg. 3. The method of claim 1 wherein the active ingredient is the hydrochloride of a compound of formula I or its 1,5-hydrate (sesquihydrate).