The present invention relates to new macrolide derivatives, in particular new tylosin derivatives of the formula (IIa), a pharmaceutical or veterinary composition comprising the derivatives; a method for preparation thereof; a method for treating and/or preventing bacterial infections in an animal, wherein the method comprises administering the derivatives or the composition; and a use of the derivatives for the manufacture of medicaments for treating and/or preventing bacterial infections in an animal.
                            本发明涉及新的大环内酯衍
生物,特别是公牛素衍
生物的新型式(IIa),其中包括该衍
生物的制药或兽医组合物;其制备方法;一种用于治疗和/或预防动物细菌感染的方法,其中该方法包括给予该衍
生物或组合物;以及该衍
生物的用途,用于制造治疗和/或预防动物细菌感染的药物。