CS195692B2 - Method of producing pharmaceutically active 1-phthalazone derivative - Google Patents

Abstract

Preparation of a phthalazone of the formula I <IMAGE> by reaction of a compound of the formula II <IMAGE> in which R is an acyl group, with isobutylene in the presence of a catalyst and subsequently hydrolysing the product obtained. The said compound of the formula I is also alternatively prepared by reacting an acid halide of the compound of the formula II in the presence of a catalyst with tert.-butanol to give the compound of the formula III and then hydrolysing it. The compound obtained is a pharmaceutical active compound for the treatment of haemorrhage, thrombosis and atherosclerosis.

Description

R is acetyl, propionyl or benzoyl.

kde '. . . . · ' ^! '. .

R is as defined above; 's' isobutene. in the presence of a catalyst, or. by converting the compound - general. .vzorce. II. v. the corresponding 7-acid halide, which is then reacted with tert-butanol in the presence of a catalyst. . .

In the Belgian 'patent -' file. ' '787' 139 states. The process of claim 1, wherein the alkoxycarbonyl-4-hydroxymethyl-1-phthalazones have valuable properties for the treatment of bleeding, thrombosis and atherosclerosis. Further study of the metabolic pathways in animals and clinical trials with 7-ethoxycarbonyl-4-hydrohydroxymethyl-1-phthalozone showed that this compound, when administered to the animal, was a xy compound, with the result that the duration of the biological effect of this compound is relatively short. It was found that . 7-tert-butoxycarbonyl-4-hydroxymethyl-1-phthalazone resists metabolic degradation and has, in comparison with the corresponding alkoxycarbonylated groups or humans, the corresponding 7-carbonyl compounds with. direct. long-term biological effects.

The tert-butoxycarbonyl-4-hydroxyniethyl-1-phthiazole derivative can be prepared by the reaction described in the above-mentioned Belgian patent specification. can be schematically represented as follows:

Í / J

In this procedure. The 4-carboxyl group to be converted into the hydroxymethyl group inevitably esterifies to form a tert-butoxycarbonyl group, which is ultimately converted to the L-V-H-5-moiety group. the fact that the commercial preparation of tert-butyl esters is complex and expensive is the method described above. of said patent, commercially disadvantageous if it is the above reaction scheme. ·

It has now been found that the desired 1-phthalazone compound can be prepared on a technical scale more advantageously than the hitherto known processes by carrying out the process described in U.S. Pat. of the above-mentioned patent first prepares the ethoxycarbonyl-4,1-hydroxymethylmethyl-phthalazone, which is then hydrolyzed and acylated, and the resulting compound of formula II is then converted to its tert-butyl ester of formula III, which is then hydrolyzed according to the process of the invention.

The compound of formula (I) is effective for preventing athtroscopy and inhibiting cholesterol deposition on arterial walls as found in experimental cholesterol-induced atherosclerosis; its effect is about three times greater than that of the corresponding ethoxycarbonyl derivative. The compound obtained. the method of the invention also prevents the increase in blood coagulability and thrombogenicity induced by cholesterol or adrenaline; its effect is also about five times greater than that of the corresponding ethoxycarbonyl derivative. The compound produced by the process of the present invention is thereby. more effectively, it prevents shortening of blood clotting time as well as '1 increased platelet aggregation'. in humans, induced by adenosine diphosphate.

It has further been found that the compound produced by the process of the invention is effective for. reducing and normalizing elevated blood pressure in a hypertension test in spontaneously hypertensive rats, whereas the corresponding ethoxycarbonyl derivative has no significant effect on elevated rat blood pressure. This activity of the compound obtained by the method of the invention is probably related to its inhibitory effect on cyclic AMP-phosphodlesterase, which is exemplified by the following bioassays.

The compound obtained by the process of the invention is therefore active. for the treatment of higher blood pressure, atherofcleric strombotic diseases. It is also optionally suitable for the treatment of diseases caused by cyclic AMP malfunction; examples of such diseases are cancer, mental and neurological. difficulties, hormonal disorders and heart muscle failure.

The starting compounds used in the process according to the invention can be prepared from the compounds described in Belgian patent 787 139. For example, by hydrolyzing 7-Oxycarbonyl-11-hy (hydroxymethyl-phthalazine described in the aforementioned patent, followed by acylation with acylanhydride or psdle chloride) In the known process, 4-acyloxymethyl-17-carboxy-phthalazone, corresponding to the compound of formula (I), is obtained. A suitable acyl group is acetyl.

The reaction of a compound of formula II with isobutylene can be carried out in the presence of a solvent such as dioxane or tetrahydrofuran. Preferably, isobutylene is present. is used in an amount greater than equimolar, and preferably concentrated acid is used as the catalyst for this reaction. sulfuric. The reaction mixture, preferably placed in a high pressure vessel or reactor, is stirred at a temperature ranging from 0 to 60 ° C.

The reaction of the acid T-halide with a tertiary butane can be carried out without solvent using an excess of anhydrous tertiary butane. . To the reaction mixture. it is advantageous to add a catalyst or dehydrating agent, for example. dimethylaniline, diethylaniline, pyridine, collidine or magnesium. The reaction is preferably carried out at a temperature ranging from. 0 to 150 ° C,. especially at the boiling point of tertiary butanol.

. The acyl group of the compound of formula III thus obtained is removed. known by _; by a partial excess of a base such as potassium hydroxide or potassium carbonate to form a compound of formula I.

The products obtained by the above processes are readily isolated and purified by conventional means. as exemplified in the examples below. ,

The compound prepared by the method of the invention may be administered alone or may form a component of pharmaceutical compositions such as powders, tablets, granules, capsules, lozenges, suspensions and other dosage forms for oral administration, and solutions, suspensions and others dispensers. forms for parenteral administration. An effective amount of a compound of formula I may be readily varied according to the intended dosage, but is usually 0.1. 80% of the total amount of carrier or ^e ners of a compound of formula I. · It follows that the compound of this invention, can be used at any desired concentration required for application at doses of 1-100 mg / kg body weight · day . ·

The carrier or diluent may be a pharmaceutically acceptable liquid or solid; · The term "carrier" also refers to components of medicaments which enhance the effect of the medicament itself. Examples of the liquid carrier are distilled water for injection, isotonic sodium chloride solution, Ringer's solution, Locke's solution, polyethylene glycol, ethyl alcohol, propylene glycol, glycerol and vegetable oil. The solid carrier may be, for example, sodium chloride, glucose, lactose, starch, sucrose, cetyl alcohol, cocoa butter and spermaceti.

The following examples illustrate the invention in greater detail, but without limiting its scope.

Example 1

Preparation of 4-acetoxymethyl-7-tert-butoxycarbonyl-1-phthalazone

To ^the memory button shifts -trubice ^ i · were added 1.2 g of 4-acetoxy-methyl-7-carboxy-phthalazone a decomposition point of 252-253 ° C and 50 ml of dioxane, after which the tube was cooled with a dry ice-acetone . 12 ml of isobutylene and then 4 ml of concentrated sulfuric acid are added to the tube with magnetic stirring. After closing the tube, the contents are stirred for 10 hours at room temperature. After this time, the contents were poured into 10% aqueous sodium carbonate solution and the mixture was then extracted with ethyl acetate. The extract was dried (MgSO4) and evaporated. The residue was recrystallized from ethanol to give 780 mg of 4-acetoxymethyl-7-tert-butoxycarbonyl-1-phthalazone, m.p. 202-203 ° C.

IR spectrum (KBr cm ^-1 ): 1740, 1720, 1660, 1360, 1295, 1240, 1160, 1120 and 1035.

2. A mixture of 2 g of 4-acetoxymethyl-7-carboxy-1-phthalazone and 20 ml of distilled thionyl chloride is gently heated for 3 hours at 70 to 80 ° C. Remove excess thionyl chloride. Remove under reduced pressure. Add 10 ml of anhydrous benzene to the residue. The benzene was removed again under reduced pressure and the residue was dissolved in 30 ml of anhydrous tert-butanol. 2.2 ml are added to the solution with stirring. Dimethylamine and the mixture are heated at reflux for 30 hours in the absence of moisture The solvent is then removed under reduced pressure and the residue is basified with aqueous sodium carbonate solution. The mixture is extracted with ethyl acetate, the extract is dried and the solvent is removed. The residue was recrystallized from ethanol to give 1.2 g of 4-acetoxymethyl-7 - erc.butoxykarbonylll-phthalazone, mp 202 to 203 ⁱⁿ C..

The IR spectrum is identical with the IR spectrum of the compound obtained according to paragraph 1.

Preparation of 7-tert-butoxycarbonyl-4-hydroxymethyl-1-phthalazone, 3.4 g of 4-acetoxymethyl-7-tert-butoxycarbonyl-11-phthalazone are added to a solution of 1.8 g of potassium hydroxide in 150 ml of ethanol. The reaction mixture was stirred at room temperature for 3 hours and then saturated with carbon dioxide. The reaction mixture was concentrated under reduced pressure and the contents of the flask were poured into water and extracted with ethyl acetate. The extract was dried and the solvent was removed. The residue was recrystallized from ethanol-n-hexane to give 2.8 g of 7-tert-butoxycarbonyl-4-hydroxymethyl-4-phthalazone, m.p. 270-272 ° C.

IR spectrum (KBr, cm -1): 3500 (broad), 1730, 1660, 1370, 1310, 1270, 1162, 1130, 1030;

mass spectrum, m / e 276, (M &lt; + &gt;), 220, 203, 191.

Biological tests

Inhibitory effect of a compound obtained by the method of the invention on platelet aggregation in human blood plasma in vitro

The compound obtained by the method of the invention has a marked inhibitory effect on the aggregation of platelets in human blood plasma induced by ADP (adenosine diphosphate) or adrenaline in vitro.

Human CPRP (High Platelet Citrate Plasma) samples are incubated at 37 ° C for 200 seconds with physiological saline containing varying amounts of test compound, and the volume of this solution · Is · 0.1 sample volume · CPRP. Add 3 μΐηοΐγ ADP or 1 µg adrenaline to the mixture. The primary and secondary clustering intensity is measured by a platelet aggregation meter (Chrono-Lo / Model 300).

For each of the above samples that were incubated with the test compound, the clustering intensity of the platelets induced by ADP or adrenaline was compared to the clustering intensity of the same sample. Incubated with physiological solution. This ratio shall be expressed as a percentage, taking as the 100% the intensity of the agglomeration induced by the solution incubated with the saline solution. The results are presented in Table I.

The intensity of primary and secondary platelet aggregation is measured by the method described by H. Jamazaki, T., Sano, et al. 'in the article "Platelet Functions · in Thromomboem8 Bolic Disorders" of the magazine "Thrombosis et ·

Diatheses '· Haemorrhagica' and in the 'references' mentioned in this article.

As can be seen from Table 1, the compound prepared by the process of the invention inhibits ADP-induced or adrenaline-induced primary aggregation with approximately comparable activity to that of 4-hydroxymethyl-1-phthalazone described in Belgium. and 7-ethoxycarbonyl-4-hydroxymethyl-1-phthalazone, described in Belgian patent 789-139. However, the compound obtained by the process of the invention inhibits the secondary agglomeration much more effectively than the above-mentioned compounds. Indeed, the compound obtained by the method of the invention inhibits ADP or adrenaline-induced secondary aggregation, statistically significantly at a concentration of 1 µg to 2.5 µg / ml, while 7-ethoxycarbonyl-4-hydroxymethyl-1-phthalazone inhibits secondary agglomeration at a concentration of '5' to 10 µg / ml.

10 ’

2. Inhibitory effect of a compound obtained by the method of the invention on cyclic AMP-phosphodistasis in the rabbit aorta wall and platelets in human blood plasma.

The compound prepared by the method of the invention is characterized by a marked inhibitory effect against cyclic AMP-phosphodine esterase in the rabbit aorta wall and platelets in human blood plasma.

The liquid above the homogenizing material from the inner and middle layers of the rabbit aorta wall or from human plaque with a high platelet content is incubated with a reagent mixture consisting of cyclic AMP (ade-nosin-3 ', 5'-cyclic monophosphate), labeled with tritium and from various amounts of the test compound. j ;.

The incubated mixture is purified by column chromatography and the fraction containing nucleotides is quantitatively analyzed by computer. for liquid scihtilation.

Table II shows the inhibitory effect of these compounds on cyclic? -Phosphodyl esterase. The figures in the table indicate the amount of test compound that is required to achieve ^? 50% inhibition of cyclic AMP-phosphodiesterase.

As is apparent from Table 11, the compound obtained by the process of the invention is much more effective for inhibiting diphosphoesterase than theophylline, caffeine, or hitherto known compounds. That is, the compound obtained by the process of the invention is effective for increasing the concentration of cyclic AMP- in the plate. in the wall.

- КАП iso (mticayj).

aortic wall ^f

Compound plates (lltlské) inner layer middle layer (rabbit) (rabbit) 7-ethoxycarbonyl-4-hydroxymethyl-1-phthalazone (control) > a 57 52 1'44 theophylline (control) · ₉₁ . '127. 155 caffeine (control) 350 . - '’. 4β0 7-tert-butoxycarbonyl-4-hydroxymethyl-1-phthalazone (according to the invention) /  22nd 13.4 48

This test is performed following the procedure _; written by H. Hidaka and M. Shlbuya, in "A New Assay of Cyclic INucleotide Phosphoraseterase and its Applicatioň to Humans", published in BiQChemical Medlcine. >

3. The hypothalamic effect of a compound obtained by the method of the invention in. spontaneously hypertensive ^rats

The compound obtained by the method of the invention has a unique hypotensive effect on spontaneously hypertensive rats. Spontaneously hypertensive rats (SH-rats) are obtained by selective selection of spontaneously hypertensive rats and continuous breeding with hypertensive animals of the opposite sex; they may be genetically hypertensive. Hypertension spontaneously hypetriene of rat rats is markedly similar to essential hypertension in humans; therefore, these animals were used to test for this disease, i

Known compounds 4-hydroxymethyl-1-phthalazone a; 7-ethoxycarbonyl-4 ^: hydroxymethyl-1-phthalazone is not characterized by a significant hypotensive effect at intraperitoneal oral doses of up to 50 mg / kg. In contrast, the compound obtained by the method of the invention has a marked hypotensive effect at doses of 0.78 to 50 mg / kg for intraperitoneal or oral administration, as shown in the table of favors.

In the blood pressure test, SH rats weighing 210-250 g each and aged 13-15 weeks are used; the test compounds are administered intraperitoneally. Each of the values shown in Tables IIIa and b is the average of the values observed in the three rats.

195692 at 12  , . TABLE lila ' Compound Blood pressure (dose: 50 mg / kg) time from application of compound h before 1 3 6 24 48

4-hydroxymethyl- blood

-l-phthalazone 7-ethoxycarbonyl- blood pressure 183 178 179 180 182 184 -4-hydroxymethyl- pressure -1-phthalazone 178 165 176 180 179 184

TABLE Illb

Compound: 7-tert-butoxycarbonyl-4-hydroxymethyl-1-phthalazone

Dose Blood pressure and decrease,% mg / kg time from compound application h

before 1 3 6 24 48 50 blood pressure 183 165 165 143 173 168 % decrease 9.8 9.8 21.9 5.5 8.2 12.5 blood pressure 178 177 158 140 160 · 167 % decrease 0.6 11.2 21.4 10.1 6.2 3,1, blood pressure 187 183 Í67 140 173 183 % decrease 2.1 10.7 ’ 25.1 7.5 2.1 0.78 blood pressure 190 180 163 163 180 188 % decrease 5.3 14.2 14.2 5.3 1.1

4. Toxicity tests with negative compounds. These tests are performed on mice by oral administration. Tests The toxicity test results (LD 50) of the toxicity compound show that this compound is comparatively nontoxic by the method of the invention. are given in Table IV as compared to TABLE IV

Compound. LD 50 (mg / kg)

4-hydroxymethyl-1-phthalazone (known) 4,000 7-ethoxycarbonyl-4-hydroxymethyl- -1-phthalazone (known) 5,000 7-tert-butoxycarbonyl-4-hydroxy- methyl-1-phthalazone (according to the invention) 4,600

BEFORE YOU INVENTED

Claims (1)

BEFORE YOU INVENTED A process for the preparation of a pharmaceutically active 1-phthalazone derivative of the formula I, characterized in that the compound of the general formula III (I) is hydrolyzed wherein: R is acetyl, propionyl or benzoyl. séverográfLa, n. p., plant 7, Most