| 摘要 |
Esters of the antibiotic pleuromutilin or its hydrogenation product are obtained by reacting pleuromutilin or its hydrogenation product with an ester-forming derivative of an acid selected from isocyanic acid, an aliphatic monocarboxylic acid having from 3 to 19 carbon atoms, a haloformic acid or monohaloacetic acid, an aliphatic dicarboxylic acid having from 3 to 14 carbon atoms, or a sulphonic acid. The acid may contain an additional group capable of reacting with a base to form a salt; in which case, the first-formed ester is reacted with a base to form the salt. The ester of the hydrogenation product of pleuromutilin may be produced by forming the ester of pleuromutilin and hydrogenating the ester before or after treatment with the base to form the salt. Pleuromutilin has the formula <FORM:1111009/C2/1> On hydrogenation the vinyl group of pleuromutilin is hydrogenated to an ethyl group. Pleuromutilin, originally named antibiotic BC 757, was produced by the cultivation of Clitopilus passeckerianus (Pil.) Sing. NRRL 3100 in accordance with Specification 1,111,010. Typical esters are the succinate, monopalmitate, a - carboxyethylcarbamate, 1,3 - dicarboxypropylcarbamate, beta - sulphopropionate and m-sulphobenzoate. An animal feed or feed supplement comprises one or more esters of pleuromutilin or its hydrogenation product. Conventional feed supplements containing penicillium mycelia may be used. |
