DE518516C - Process for the preparation of basic bismuth salts of organic arsic acids - Google Patents

Description

Process for the preparation of basic bismuth salts of organic arsinic acids In the Comptes Rendu.s i8o [z925], p. I 9; i. describes 1. e v a d i t i a basic, Bismuth salt of 3-acetylamino-q-oxybenzene-i-arsinic acid, which is soluble in alkalis by reacting the sodium salt of arsic acid with bismutyl potassium sodium tartrate is obtained. An improved method is disclosed in English patent specification 266 82o described for the production of such salts, but this itself is of little practical use is because various precautionary measures must be observed when performing it, without the poor yields and preparations that are difficult to isolate are obtained.

It has now been found that it can be done in a considerably simpler way arsenic preparations containing bismuth, which are considerably better than the above bismuth salts characterized by reduced toxicity with a very good anti-parasitic effect can, if you combine the alkali salts of organic arsinic acids with (the solution of an inorganic Wis.mutsalzes converts and thereby the acid radicals of the bismuth salt by means of alkali quite dull. From the procedure described in Arch. Der Pharm. 263 [1925], p. 72 [ The present process differs through the use of inorganic bismuth salts and by the amount of alkali used. While in the new process all Acid radicals .des Wisinut salt are blunted, is in the known process a far insufficient amount of alkali is used for this purpose.

The preparations obtained by the new process are in contrast insoluble to the salts mentioned above and are particularly suitable for depot treatment of trpanosomal and spirochete diseases. Examples i. 2j, 5.9 3Acety: lamino-q.-oxybenzo, l-i-arsic acid are dissolved in 100 ccm of 2N sodium hydroxide solution. A solution is left with vigorous stirring of 48.5 g of bismuth nitrate in 18.5 g of glycerine and 97 g of water are added dropwise. Then it will be The bismuth salt which has precipitated is neutralized by adding 50 ccm of 2N sodium hydroxide solution sucked off ,. with water, . Alcohol and ether washed and the product in vacuo dried. The preparation is a pale yellowish colored powder.

2. In the same way as in Example i, 25.9 g p-Acetylaminoben: convert zolaric acid into its Wisinut salt.

3. 27.29 i-Methy l-2-oxobenzimidazole dihydride (2, 3) -5-arsinic acid, prepared according to patent specification 446 545, to be dissolved in 100 ccm of 2 N # sodium hydroxide solution and treated with Nismuth nitrate, as described in example i, implemented. The bismuth salt is suctioned off, washed and dried.

4-459 of the formal, dehydebisulfite compound of 3-amino-4-oxybenzoliarsinic acid prepared according to example 2 of patent specification 459 362 are dissolved in 150 cc of water. While stirring vigorously, leave one according to the example. I add the prepared solution of 48.5 g of bismuth nitrate dropwise, then neutralize by adding 50 ccm of 2N sodium hydroxide solution and separates the precipitated salt, as indicated in Example i.

Claims (1)

PATEN TANSPRUCFI Process for the preparation of basic bismuth salts organic arsinic acids, characterized in that one in aqueous solution the alkali salts of arsinic acids, inorganic, in water by adding glycerine or other suitable solubilizers dissolved wis, mutsal, ze under blunting all acid radicals of the bismuth component can act.