A series of 20-deoxo-20-cyclic (alkylamino) derivatives of tylosin, desmycosin, macrocin and lactenocin was prepared by reductive amination of the C-20 aldehyde group. The majority of the compounds were prepared using metal hydrides (sodium cyanoborohydride or sodium borohydride) as the reducing agents and a suitable cyclic alkylamine. Subsequently, a more convenient procedure was developed using formic acid as a reducing agent. The C-20 amino derivatives prepared from desmycosin exhibited good in vitro antimicrobial activity against Pasteurella haemolytica and Pasteurella multocida (MIC range of 0.78 approximately 6.25 micrograms/ml) as well as Mycoplasma species (MIC range of 0.39 approximately 6.25 micrograms/ml). Several derivatives showed excellent oral efficacy against infections caused by P. multocida in chicks. One of these derivatives, 20-deoxo-20-(3,5-dimethylpiperidin-1-yl)desmycosin (tilmicosin or EL-870) was selected for development as a therapeutic agent for pasteurellosis in calves and pigs.

中文翻译：

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20-deoxo-20-（3,5-二甲基哌啶-1-基）去霉菌素（替米考星，EL-870）及其相关环状氨基衍生物的合成和抗菌评估。

通过C-20醛基的还原胺化反应，制备了一系列泰乐菌素，脱粘菌素，大霉素和乳酸菌素的20-脱氧-20-环（烷基氨基）衍生物。大多数化合物是使用金属氢化物（氰基硼氢化钠或硼氢化钠）作为还原剂和合适的环状烷基胺制备的。随后，开发了一种使用甲酸作为还原剂的更方便的方法。由去粘菌素制备的C-20氨基衍生物对溶血巴斯德氏菌和多杀巴斯德氏菌（MIC范围为0.78约6.25微克/ ml）以及支原体种类（MIC范围为0.39约6.25微克/ ml）表现出良好的体外抗菌活性。几种衍生物对鸡多杀性疟原虫引起的感染显示出优异的口服功效。这些衍生物之一