DE1008284B - Process for the production of low-toxic basic salts of Streptomyces antibiotics - Google Patents

Description

Process for the production of low-toxicity basic salts of Streptomyces antibiotics The invention relates to a method for the production of Antibiotic eucine salts of Streptomyces antibiotics with reduced toxic properties with constant antibacterial effectiveness.

It is known that certain basic strains produced by Streptomyces Antibiotics have a toxicity that makes their general use difficult. These include, for example, streptomycin and dihydrostreptomycin or neomycin and Viomycin. This is the case with streptomycin, dihydrostreptomycin, neomycin and viornycin the occurrence of hearing damage or imbalance caused by Damage to the eighth cranial nerve, to be feared and may cause cessation give the treatment. With neomycin and viomycin, kidney damage can also occur appear.

In patent 951567 and in patent 954 874 it has now been shown that the basic antibiotics produced by Streptomyces species can be detoxified by chemically reacting them with pantothenic acid or its derivatives, expediently converted into salts.

In the patent application C 10419 IV b / 12 c it was shown that the basic Streptomyces antibiotics can also be detoxified by the fact that they be mixed with a water-soluble zinc salt in such amounts that the amount of zinc 0.1 to 10%, preferably 0.2 to 3%, of the amount of the antibiotic, where at least partially complex compounds of the basic antibiotic and the zinc salt and the preparations are preferably used in the form of solutions.

Basic Streptomyces antibiotics are now used according to the method according to the invention . detoxified by salt formation with leucine without affecting their antibiotic effectiveness is reduced.

The leucine becomes the basic streptomyces antibiotic in a lot from 5 to 1500 / a, calculated on the amount of the free base of the antibiotic, preferably added in an amount of 15 to 1251 / o, so that at least partially one Salt formation takes place between the basic Streptomyces antibiotic and the leucine.

The leucine can optionally also be used in a mixture with the detoxifying compounds described in patent 951567 and in patent 954 874 and in patent application C 10419 IV b / 12 o, for example together with zinc salts.

The therapeutic effect achievable by the present method results from the following comparative experiments a) The dose in mg, based on 20 g mouse, when administered 50% of the animals die (DL "), is about 15 to 18 for streptomycin sulfate According to the information provided by the DL., are based on the fact that animal experiments carried out with the same animal material at the same time may only be compared with one another.The animals have different sensitivity depending on the strain, nutritional status, etc. If the test animals are given a mixture of streptomycin sulfate and leucine so that the animals receive 20 mg of leucine per 20 g of mouse, the DL., in animals for which the DL., for streptomycin sulfate alone is about 15, is now 20.4; the toxicity has therefore been correspondingly reduced.

In the case of dihydrostreptomycin sulfate, the DL., In mg per 20 g mouse, is about 28. If 20 mg of leucine is also administered per 20 g mouse, the DL. Is now about 35. Here, too, there has been a strong reduction in toxicity.

The experiments were carried out in such a way that mice with a mean Weight of 20 g used and the antibiotic substances injected subcutaneously became. Half of the test animals only received the antibiotic while the other half also received the leucine, also administered subcutaneously. It was then determined how many animals died in each case within the following 5 days and from this the value of the DL50 is determined.

The products according to the invention were also compared with the products known from German Patent 929 665 and German Patent 814 316 and US Pat. No. 2,643,997 with regard to the reduction in toxicity. The results are contained in Table 1 below. Since the products described in German Patent 929 665 are sparingly soluble, mixtures of the starting components were used with these products in the tests. The values given in the table below are obtained from uniform animal material and are therefore directly comparable with one another. Table 1 DL5o mg anti biotic (as base) Connection per 20 g mouse with subcutaneous injection Streptomycin sulfate 14.8 Streptomycin Leucinate ... ... 18.5 Streptomycin sulfate + deoxychol- acid (corresponding to Example 6 of German patent 929 665) ....... -1-4.9 " Streptomycin sulfate + lithochol- acid (according to example 5 des German patent 929 665) ..... 14.5 Streptomycin phosphate (U.S. Patent 2,643,997). . 15.0 Streptomycin p-amino salicylate (Example 1 of the German patent scripture 814 316) ............... 14.8 Dihydrostreptomycin Sulphate ..: .... 25.2 Dihydrostreptomycin sulfate + des- oxycholic acid (corresponding to game 1 of the German patent 929665) .... -.............. 24.9 Dihydrostreptomycin Leucinate ..... 35.7 Dihydrostreptomycin sulfate + chol- acid (corresponding to Example 3 of German patent 929 665) ..... 25.8 Dihydrostreptomycin sulfate + litho- cholic acid (according to Example 4 of the German patent. 929 665). . 24.7 Dihydrostreptomycin-p-amino- salicylate (according to example 2 of the German patent specification 814 3l6) ...................... 25.0 i \ Teomycin Sulphate ................. 7.95 i'Veomycin Leucinate ............... 9.1 Viomycin sulfate .................. '32.4 Viomycin Leucinate .... ........... 41.5 b) The fact that the antibiotic effectiveness of the basic Streptomycesantibiotika is not reduced by the salt formation with leucine results from the following comparative experiments. For the experiments, ten white mice were infected with Mycobacterium tuberculosis strain H37 Rv and then - starting 3 days after infection - treated with the substances to be tested for 6 days. The average lifespan of the animals is a measure of the tuberculostatic activity of the compounds. The streptomycin; Dihydrostreptomycin and neomycin compounds were administered subcutaneously in such amounts that 1 mg of the base of the respective antibiotic was used per day and animal. In the case of the viomycin compounds, 3 mg viomycin base were administered per day and animal under otherwise identical conditions.

The following results were obtained: Table 2 middle Connection lifetime in days Streptomycin Sulphate .............. 22.8 Streptomycin Leucinate ............. 24.1 Dihydrostreptomycin sulfate ....... 23, #r Dihydrostreptomycin leucinate. ,. . . 23.7 Neomycin Sulphate ................. 19.7 1 neor nycin leucinate ................ 20.5 Viomycin sulfate .................. 24.3 Viomycin Leucinate ................ 24.8 Control (untreated) .......... 18.5 From this table it can be seen that the animals treated with the antibiotic ucinates had a slightly longer lifespan in all experiments, but otherwise there is practically no difference between the effectiveness of the antibiotic sulfates and the antibiotic ucinates.

This therapeutic effect is not only shown by the pure new antibiotic salts, but also their mixtures with other basic Streptomyces antibiotics or other antibiotics, such as penicillin or penicillin salts.

The following examples illustrate the present invention.

Example 1 Dissolve in succession under sterile working conditions 0.15 g of leucine and 1 g of streptomycin sulfate in 10 cc of water. The solution obtained can be used immediately. The solution can also be freeze-dried and in this way a solid substance which can be used well is obtained.

Example 2 The example used is used instead of streptomycin sulfate 1 the same amount of dihydrostreptomycin sulfate and gets the same result. Example 3 In 250 ccm of lukewarm distilled water, 18.9 g of barythydrate [Ba (OH) 2 - 8H20] and then 15.7g of leucine dissolved. To the solution obtained is added a solution of 30.4 g of streptomycin sulfate in 100 cc of distilled water with stirring. The barium sulfate formed is filtered off and the filtrate is freeze-dried. Man receives 35 g of the leucine salt of streptomycin.

F. = 250 ' (decomposition). The nitrogen content of 14.36% found in the analysis agrees with the calculated value of 14.36%.

Example 4 Proceed as in example 4, but replace that in the example 4 used streptomycin sulfate 29.8g dihydrostreptomycin sulfate. 39 g of the leucine salt of dihydrostreptomycin are obtained.

M.p. = 220 ° (decomposition); N (calculated): 14.33%, N (found): 14.420 / a.

Example s 19.65 g of leucine and 25.35 g of neomycin are dissolved in 1000 cc distilled water and treat the solution with 1 g of decolorizing charcoal. The filtered Solution is freeze-dried. 45 g of the leucine salt of neomycin are obtained.

M.p. = 250 ° (decomposition); N (calculated): 10.83 0/0, N (found): 11,531 / o.

Example 6 In 250 cc of distilled boiled water at 80 ° successively with stirring 18.9 g of barythydrate and then 15.72 g of dl-leucine dissolved. To a solution of 30.2 g of 970% dihydrostreptomycin sulfate is added to the cooling and 500 cc of distilled water. The reaction mixture is kept for 11/2 hours at a temperature of -I-2 °, then treated it with decolorizing charcoal and filtered using a filter aid. The resulting solution is freeze-dried. 37 g of the dl-leucine salt of dihydrostreptomycin are obtained. The melting point is at about 220 ° with decomposition.

N (calculated): 14.33 0/0, N (found): 14.381 / 0. Example ? Man proceeds as in Example 6, but replaces the dihydrostreptomycin sulfate used there by 30.25 g of 96.5% streptomycin sulfate. 37.5 g of the dl-leucine salt are obtained of streptomycin. The melting point is about 250 ° with decomposition.

N (calculated): 10.830 / 0, N (found): 11.12% .. Example 8 The procedure is followed as in Example 7, but replaces the dihydrostromycin sulfate used there with 26.75 g of 96.5% neomycin sulfate. 23 g of the dl-leucine salt of neomycin are obtained. The melting point is about 250 ° with decomposition.

Example 9 A suspension of 2.62 g of 1 (-) - leucine in 50 cc of warm 3.15 g of Ba (OH) 2- $ H20 are added to water. About the resulting barium leucinate solution a solution of 6 g of viomycin sulfate in 50 cc of water is added. The reaction mixture is cooled to 1 to 2 ° for a few hours and then the barium sulfate formed filtered off. The filtrate is subjected to freeze-drying, whereby the Viomycin leucinate, which melts at 212 ° with decomposition, is obtained.

N (calculated): 22.1%, N (found): 22.50 / a.

The fact that according to the present invention really salts arise from the fact that the leucine as such is very sparingly soluble in water is while the reaction products as well as streptomycin and dihydrostreptomycin are very easily soluble in water.

The solubilities of the compounds according to the invention in water at 25 ° are summarized in the table below: 1-Leucine ........................ about 2.40 / 0 dl-leucine ...................... about 1 0/0 1-leucine salt of dihydrostreptomycin 18 0/0 1-leucine salt of streptomycin ...... .. 15 0/0 1-leucine salt of neomycin .......... 10% dl-leucine salt of dihydrostreptomycin 9 0/0 dl-leucine salt of streptomycin ...... 8.5% dl-leucine salt des neomycin ......... 9 0 / a 1-leucine in a 10% solution of the leucine salt of streptomycin ..... 0.30 / 0

Claims (1)

PATENT CLAIM: Process for the production of low-toxicity salts of basic Streptomyces antibiotics according to the process of patents 951567, 954874 and patent application C 10419 IV b / 12o, characterized in that basic Streptomyces antibiotics, preferably streptomycin, dihydrostreptomycin, neomycin or viomycin-containing antibiotics or mixtures thereof with 5 to 150% leucine, calculated on the amount of the free antibiotic, preferably with 15 to 125% leucine in a known manner in aqueous solution. References considered: U.S. Patent Nos. 2,646,427, 2,643,997; French Patent No. 1019 552; British Patent No. 720 166; German patent specification No. 814 316. Earlier rights cited: German patent No. 929 665.