DE858127C - Process for the preparation of solutions of thiosemicarbazones - Google Patents

Description

(WiGBl. P. 175)

ISSUED DECEMBER 4, 1952

P 35-47 IVa / 30 Ii D.

Thiosemicarbazones are used therapeutically, mainly ran tuberculosis. P, for them practical application it is often found disturbing that it is often only used in a few solvents, especially acids or alkalis are to be brought into solution.

It has now been found that water-miscible solvents from the group of amides aliphatic acids are excellent solvents for such thiosemicarbazones. the Solutions are expediently prepared in such a way that one first weighs the amount the substance dissolves with warming, then cools and with the solvent to the desired Replenishes volume.

In the warmth, sometimes even at body temperature, In some cases, considerably concentrated solutions of the thiosemicarbazones can be found produce. The following examples can be used for solutions that remain clear at ordinary temperature are given:

-L-acetylaminobenzalthiosemicarbazone = Λ

4-aminobenzalthiosemicarbazone = 1.5

4-propionylaminobenzalthiosemicarbazone ... = C

4-Benzoylaminobenzalthiosemicarbazone .... = D

4-anisalthiosemicarbazone = E

4-Alhloxybenzalt'hiosemicarbazone = F

4-aminobenzalthiosemicarbazone / phosphorus derivative (produced by the action of Phosphorus oxychloride to 4-aminobenzalthiosemicarbazone dissolved in pyridine and

subsequent treatment with water) ... = G

Anisal-4-aminobenzalthiosemicarbazone .... = H

The table below, in which the thiosemicarbazones listed above with letters are used, gives the percentages of the approximate solubilities in the specified Solvents at room temperature

A BCDEFGH formamide

o, 5

Methylacetamide
ίο with 10% water 4

example

To execute one solves z. B. in a volumetric flask 4 g of A in about 70 ecm methylacetamide, the 10%> water are added by briefly heating in the water bath, cools down and fills up to 100 ecm with the ooVoigen methylacetamide. Instead of Mixtures of the pure solvents can also be used. For the mixtures, for example Water-miscible glycols or their ethers are used, which, as at the same time was found, are also suitable as solvents for thiosemicarbazones. For example can be 3 parts of A in a mixture of 70 parts of diglycol monoethyl ether and 30 parts Dissolve formamide to a solution that remains clear at ordinary temperature. Partly tolerated the solutions, especially the more dilute ones, also contain an addition of water, causing a crystallization does not occur or takes a long time. In the case of methylacetamide, water is added required or appropriate to prevent the solvent from solidifying.

Claims (1)

Claim: Process for the preparation of solutions of therapeutically useful thiosemicarbazones, characterized in that the water-miscible organic solvents Solvents from the group of the amides of aliphatic acids, if appropriate with the addition of water, can be used. © 5518 11.52