CH641190A5 - DAUNORUBICIN DERIVATIVES, THEIR PREPARATION AND THE PHARMACEUTICAL COMPOSITIONS CONTAINING THEM. - Google Patents

Description

The present invention relates to new dauno-45 rubicin derivatives of general formula

0 OH

CO CH2 OCORj UOH

(I)

CH - CH,

| H-R2 CH - CHOH -0

CH - CH,

55 as well as their addition salts with acids, their preparation and the compositions containing them.

In the general formula (I)

- the symbol Rj represents a radical of general formula

60

-CH

^ X-R3

\

have)

X-r3

65 in which the symbols X, which represent an oxygen or sulfur atom, are identical, and the symbols R3 represent alkyl, phenyl or phenyl radicals substituted in the para position by a methyl, methoxy or methylthio radical, or together form a

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641190

alkylene radical containing 2 to 4 carbon atoms, or the symbols X are different and the symbols R3 together form an alkylene radical containing 2 to 4 carbon atoms,

- and the symbol R2 represents a radical of general formula r4-ch-co-

i (iii)

nh2

in which R4 represents a hydrogen atom or an alkyl, phenyl or benzyl radical.

It is understood that the radicals and alkyl portions mentioned above, which are straight or branched, contain 1 to 4 carbon atoms and that the products of general formula (I) mentioned above are derived, where appropriate, from the forms D , L, and DL of the amino acid of general formula r4-ch-c00h i (iv)

nh2

in which R4 is defined as above.

According to the invention, the products of general formula (I) are prepared by the action of a reactive derivative of an amino acid of general formula (IV), the amine function of which is previously protected, on a daunorubicin derivative of general formula

OH

CO CH. OCOR.

NH.

CH.0

- CH - CHOH - CH - CH.

in which R! is defined as above, or on one of its salts.

The amine function of the amino acid of general formula (IV) can be protected by any method known per se for blocking the amino radical of an amino acid and the blocking and unblocking conditions of which are compatible with the stability of the molecule.

The acid function of the amino acid of general formula (IV) can be activated either in the form of mixed anhydride, or in the form of reactive ester.

1) The acid function of the amino acid of general formula (IV) can be activated by formation of a mixed anhydride by reaction of the amino acid with, for example, an ethyl chloroformate, iso-butyl or dry .-butyl.

When the amino acid of general formula (IV) is used in the form of such a mixed anhydride (which can be prepared in situ), the amine function is protected beforehand by a radical [(biphenylyl-4) -2 propyl -2] oxycarbonyl which can be introduced according to the method described by P. Sieber and B. Iselin, "Helv. Chim. Acta ”, 51, 622 (1968), and which is easily eliminated in dilute acid medium, in particular in the presence of hydrochloric acid.

The condensation of the mixed anhydride of the product of general formula (IV) with the daunorubicin derivative of general formula (V) is then carried out in an anhydrous medium in an organic solvent such as methylene chloride or tetrahydrofuran, in the presence of a nitrogenous base such as triethylamine or N-methylmorpholine, at a temperature between -20 and 0 ° C. Preferably, one operates under nitrogen.

The removal of the protective group from the amine function is carried out in the presence of hydrochloric acid in an organic solvent such as methylene chloride at a temperature between 4 and 25 ° C.

2) The acid function of the amino acid of general formula (IV) can also be activated by esterification with hydroxylated compounds such as N-hydroxysuccinimide. This activated ester can be prepared in situ.

When operating according to this variant, the amine function of the amino acid of general formula (IV) can be protected by a group such as the trityl radical, which can be eliminated in dilute acid medium.

Under these conditions, the condensation reaction of the activated ester with the product of general formula (V) is carried out in an organic solvent such as ethyl acetate or dimethylformamide in the presence of a carbodiimide such as dicyclohexylcarbodiimide at a temperature between -15 and 25 ° C, optionally in the presence of an organic base such as triethylamine.

The products of general formula (V) can be obtained according to the method described in Belgian patent N ° 848219.

The new products of general formula (I) can optionally be purified by physical (such as crystallization or chromatography) or chemical (such as salt formation, crystallization, and then decomposition thereof) methods.

The new products according to the invention can be converted, if necessary, into addition salts with acids.

The salts can be obtained by the action of the new compounds on acids in suitable solvents; as organic solvents, use is made, for example, of alcohols, ethers, ketones or chlorinated solvents; the salt formed precipitates after optional concentration of its solution and is separated by filtration or decantation.

The new daunorubicin derivatives of general formula (I), as well as their salts, have interesting anti-tumor properties, combined with low toxicity.

They have been shown to be particularly active on graftable tumors of the mouse, in particular at doses of between 0.20 and 20 mg / kg i.p. on leukemia L 1210.

Their maximum tolerated dose determined in mice is between 0.5 and 30 mg / kg i.p.

Of particular interest are the products of general formula (I) for which Rt is a radical of general formula (II) in which the symbols X represent oxygen and the symbols R3 are alkyl radicals or else the symbols X, which are identical or different, represent oxygen or sulfur, and the symbols R3 together form an alkylene radical containing 2 to 4 carbon atoms, and R2 represents a leucyl radical.

Among these products, are more especially active:

- N (L-leucyl) diethoxyacetoxy-14 daunorubicin, and

- N (L-leucyl) (dithiolane-1,3 yl-2) carbonyloxy-14 daunorubicin.

For therapeutic use, use may be made of the new daunorubicin derivatives according to the invention either in the free state or in the form of pharmaceutically acceptable salts, that is to say nontoxic at doses d 'use.

As examples of pharmaceutically acceptable salts, there may be mentioned salts of mineral acids (such as hydrochlorides, sulfates, nitrates, phosphates) or organic acids (such as acetates, propionates, succinates, benzoates, fumarates, maleates, tartrates, theophyllinacetates, salicylates, phenolphthalinates, methylenebis-p-oxynaphtoates).

The following examples, given without limitation, illustrate the present invention.

Example 1:

In a three-necked flask, previously dried, 7.66 g of LN - [(biphenylyl-4) -2 propyl-2] oxycarb-onylleucine are dissolved in a nitrogen atmosphere in 100 cm3 of tetrahydrofuran and 2.9 ml of triethylamine are added. preserved on potash tablets. The mixture is cooled to -20 ° C. and 2.48 cm 3 of isobutyl chloroformate are added all at once. The mixture is stirred at -20 ° C. for 30 min. A solution of 12.3 g of diethoxyacetoxy-14 daunorubicin hydrochloride in 200 cm3 of dry methylene chloride containing 2.43 cm3 of triethylamine is added at once, while maintaining the temperature of the reaction medium at −20 ° C. potash tablets. The mixture is stirred for 15 min at -20 ° C. 1000 cm3 of ice water are added, decanted and the organic phase is washed three times with 200 cm3 of water. The organic phase is dried over sodium sulfate. It is filtered and concentrated to dryness under reduced pressure (20 mm of mercury) at 30 ° C. The residue is dissolved in the

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641190

4

minimum methylene chloride and this solution is poured onto a column (diameter 5 cm, height 60 cm) containing 450 g of silica gel in chloroform. Eluted successively with 4000 cm3 of methylene chloride containing 10% (by volume) of ethyl acetate, then with 5100 cm3 of methylene chloride containing 25% (by volume) of ethyl acetate, collecting the eluate in fractions of 300 cm3.

The fractions 14 to 30 are combined. It is concentrated to dryness under reduced pressure (20 mm of mercury) at 30 ° C., then drying under reduced pressure (1 mm of mercury) at 20 ° C.

11.3 g of N- [N - {[(biphenylyl-4) -2 propyl-2] oxy-carbonyl} L leucyl] diethoxyacetoxy-14 daunorubicin are thus obtained in the form of an amorphous red solid:

[a] î) = + 126 + 16 ° (c = 0.182, chloroform)

11.3 g of N- [N - {[(biphenylyl-4) -2 propyl-2] oxy-carbonyl} L leucyl] diethoxyacetoxy-14 daunorubicin are dissolved in 130 cm 3 of methylene chloride. The mixture is cooled to + 4 ° C by an ice and water bath. 25.7 cm3 of 0.77N solution of dry hydrochloric acid in dioxane is added with stirring at one time. After 10 min, 300 cm3 of ethyl acetate and 500 cm3 of ethyl ether are added. The red precipitate obtained is filtered, washed with ethyl ether and dried under reduced pressure (1 mm of mercury) at 20 ° C. The red powder is suspended in 100 cm3 of ethyl acetate. Stir 15 min and filter. The red solid obtained is washed three times with 100 cm3 of ethyl acetate and dried under reduced pressure (1 mm of mercury) at 40 ° C.

6.62 g of N- (L leucyl) diethoxyacetoxy-14 daunorubicin are obtained in the form of the hydrochloride which is a red powder:

[a] 2d ° = + 225 + 18 ° (c = 0.216, methanol)

Rf = 0.66 [Silicagel; methylene chloride / methanol / formic acid. that / water (88/15/2/1 by volume)]

Analysis:

Calculated: C 56.90 H 6.24 Cl 4.31 N 3.40%

Found: C 56.40 H 6.50 Cl 4.40 N 3.50%

Example 2:

In a dry three-necked flask, 1.33 g of LN - [(biphenylyl-4) -2 propyl-2] oxycarbonylleucine are dissolved in an argon atmosphere in 120 cm3 of anhydrous tetrahydrofuran, then 0.505 cm3 of preserved triethylamine is added on potash tablets.

Cool to -20 ° C and quickly add 0.426 cm3 of isobutyl chloroformate. The mixture is stirred for 30 min at -20 ° C. Then 240 cm 3 of methylene chloride, 0.42 cm 3 of triethylamine dried on potassium hydroxide and 2.14 g of hydrochloride (1,3-dithiolane) are added to the white suspension. yl-2) carbonyloxy-14 daunorubicin in powder form.

The mixture is stirred at -20 ° C for 45 min.

The reaction mixture is poured into 300 cm3 of ice water; the organic phase is decanted and washed with 2 times 250 cm3 of 0.05N hydrochloric acid, then with 3 times 250 cm3 of water.

The organic solution is dried over sodium sulfate, filtered and concentrated to dryness under reduced pressure (20 mm of mercury) without exceeding 30 ° C. The solid residue is dissolved in a mixture of methylene chloride containing 25% acetate ethyl (by volume) and chromatographed on 140 g of Merck silica 0.04-0.063 mm, under 0.5 bar of nitrogen.

Elution is followed by thin layer chromatography and the eluate corresponding to the pure product is concentrated to dryness under reduced pressure (20 mm of mercury) at a temperature in the region of 30 ° C.

After drying at 20 ° C under reduced pressure (1 mm of mercury), 2.44 g of N- [N - {[(biphenylyl-4) -2 propyl-2] oxycarb- are obtained.

onyl} L leucyl] (dithiolane-1,3 yl-2) carbonyloxy-14 daunorubicin in the form of a red powder.

2.44 g of N- [N - {[(diphenylyl-4) -2 propyl-2] oxy-carbonyl} L leucyl] (dithiolane-1,3 yl-2) carbonyloxy-14 daunorubicin are dissolved in 150 cm 3 of anhydrous methylene chloride.

Cool to 5 ° C, then quickly add 6.88 cm3 of 0.77N solution of dry hydrochloric acid in dioxane.

The mixture is stirred for 10 min, then the precipitate formed is filtered. The solid is washed with 100 cm3 of methylene chloride. The insoluble material is dissolved in 50 cm3 of anhydrous methanol, then reprecipitated by the addition of 150 cm3 of ethyl ether.

After filtration, washing with ethyl ether and drying under reduced pressure (1 mm of mercury), 1.3 g of N- (L leucyl) hydrochloride (dithiolane-1,3 yl-2) -14-carbonyloxy-daunorubicin are obtained. .

Rf: 0.57 [silica gel; methylene chloride / methanol / formic acid / water (88/15/2/1 by volume)]

Analysis:

Calculated: C 53.84 H 5.50 Cl 4.30 N3.39 S 7.77%

Found: C 53.90 H 5.40 Cl 4.90 N 3.20 S 7.60%

The present invention also includes medicaments consisting of a product of general formula (I) in the free state or in the state of salt, pure or in the form of a medicinal composition which contains it in association with one or more diluents or compatible and pharmaceutically acceptable adjuvants, which may be inert or physiologically active.

These compositions can be presented in any form appropriate to the intended route of administration. The parenteral route is the preferred route of administration, especially the intravenous route.

The compositions according to the invention for parenteral administration can be sterile aqueous or non-aqueous solutions, suspensions or emulsions.

As solvent or vehicle, it is possible to use propylene glycol, polyethylene glycol, vegetable oils, in particular olive oil, and injectable organic esters, for example ethyl oleate.

These compositions can also contain adjuvants, in particular wetting agents, emulsifiers and dispersants. Sterilization can be done in several ways, for example using a bacteriological filter, by incorporating sterilizing agents into the composition or by irradiation.

They can also be prepared in the form of sterile solid compositions which can be dissolved or dispersed at the time of use in sterile water or any other sterile injectable medium.

The products of general formula (I) and their salts are more particularly used in the treatment of acute lymphoblastic and myeloblastic leukemias, lymphosarcomas, Hodgkin's disease and solid tumors (lung cancer, breast cancer, cancer of the digestive tract and metastases) at daily doses generally between 1 and 5 mg / kg intravenously for an adult.

The following example illustrates a composition according to the invention. Example:

A solution containing 27.9 mg / cm3 of N- (L leucyl) diethoxyacetoxy-14-daunorubicin hydrochloride is prepared by dissolving 4.185 g of this product in pyrogen-free physiological solution in sufficient quantity to obtain 150 cm3. The solution obtained is aseptically distributed in ampoules at the rate of 3 cm3 per ampoule. The ampoules are sealed and each contain 80 mg of N- (L leucyl) diethoxyacetoxy-14 daunorubicin (base).

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Claims (4)

641190 2 1. Derivative of daunorubicin, characterized in that it corresponds to the general formula CO CH2 OCORJ NH - R. CHjO 0 OH 0 - CH - CH2 - CH - CHOH - CH - CHj in which - the symbol R! represents a radical of general formula < in which the symbols X, which represent oxygen or sulfur atoms, are identical, and the symbols R3 represent alkyl, phenyl or phenyl radicals substituted in the para position (by a methyl, methoxy or methylthio radical) or together form a alkylene radical containing 2 to 4 carbon atoms, or the symbols X are different, and the symbols R3 together form an alkylene radical containing 2 to 4 carbon atoms, and - the symbol R2 represents a radical of general formula R4-CH-CO- CH - CH, in which r, is defined according to claim 1, then eliminates the protective group and optionally transforms the product obtained into an addition salt with an acid. 4. Method according to claim 2, characterized in that a reactive derivative of the amino acid of general formula r4-ch-cooh I is made to act. nh2 in which r4 is defined according to claim 1, and the amine function of which has been previously protected by a [(biphenylyl-20 4) -2 propyl-2] oxycarbonyl or trityl radical, on a daunorubicin derivative of general formula 0 OH CO CHj OCORj IF2 CH30 0 OH 0 - CH - CH2 CH - CHOH - CH - CH, 30 nh2 in which r4 represents a hydrogen atom or an alkyl, phenyl or benzyl radical, the radicals and alkyl portions mentioned above being straight or branched and containing 1 to 4 carbon atoms, its diastereoisomeric forms and mixtures thereof, as well as its addition salts with acids. 2. Method for preparing a product according to claim 1, characterized in that a reactive derivative of an amino acid of general formula r4-ch-cooh I is made to act nh2 in which r4 is defined according to claim 1, and whose amine function is previously protected, on a daunorubicin derivative of general formula 0 OH CO CH, OCOR " NH, CHjO 0 OH 0 - CH - CH2 - CH - CHOH - CH - CHj in which Rj is defined according to claim 1, then eliminates the protective group and optionally converts the product obtained into an addition salt with an acid. 3. Method according to claim 2, characterized in that one acts, as reactive derivative of the amino acid of general formula R4-CH-C00H I nh2 in which R4 is defined according to claim 1, a mixed anhydride or a reactive ester whose amine function has been protected, on a daunorubicin derivative of general formula in which R! is defined according to claim 1, then eliminates the protective group and optionally transforms the product obtained into an addition salt with an acid. 5. A medicament consisting of a product according to claim 1, pure or in the form of a pharmaceutical composition which contains it in combination with one or more compatible and pharmaceutically acceptable diluents or adjuvants.