| 摘要 |
1,266,083. Tetracycline lactate. FAR EASTERN DETAILERS Ltd. 28 May, 1970 [6 June, 1969], No. 25840/70. Heading C2A. The novel salt tetracycline lactate, comprising a substantially equimolecular combination of tetracycline base and lactic acid, may be prepared from anhydrous materials by reacting tetracycline base in solution in an alcoholic solvent with at least a stoichiometric quantity of pure crystalline lactic acid at room temperature in an inert atmosphere, the resultant solution being concentrated in vacuo in order to promote crystallization of the tetracycline lactate, which is separated from the mother liquor by filtration. Preferably the inert atmosphere is dry nitrogen, the tetracycline base is dried prior to use at 100‹ to 105‹ C., the solvent used is anhydrous ethyl alcohol, the resulting solution is concentrated in vacuo to a quarter of its initial volume up to 40‹ C., and the tetracycline lactate obtained is purified by washing in anhydrous diethyl ether and the pure crystalline lactic acid employed is obtained from racemic lactic acid distilled in vacuo and is used immediately afterwards. Pharmaceutical antibiotic compositions comprise tetracycline lactate and a pharmaceutically acceptable carrier. The compositions may be administered orally in the form of capsules or sachets. |
