Disclosed are compounds including rifamycin derivatives having antibacterial activities, wherein the compounds have the following general formula:wherein:R is hydrogen or acetyl R1 and R2 are independently selected from the gorup consisting of hydrogen, (C1-4) alkyl, benzyloxy, mono- and di-(C1-3) alkylamino-(C1-4)alkyl, (C1-3)alkoxy, (C1-4)alkyl, hydroxy-methyl, hydroxy-(C2-4)-alkyl, and nitro or R1 and R2 taken together with two consecutive carbon atoms of the pyridine nucleus form a benzene ring optionally substituted by one or two methyl or ethyl groups and R3 is hydroxyalkyl (C1-4). In addition, processes to obtain these compounds are described.The compounds have antibacterial activity.揭示包括具有抗菌活性之利福黴素(rifamycin)衍生物之化合物,其中該等化合物具有如下通式:其中:R為氫或乙醯基,R1及R2分別係選自於由氫、(C1-4)烷基、苄氧基、一-及二-(C1-3)烷基胺-(C1-4)烷基、(C1-3)烷氧基、(C1-4)烷基、羥-甲基、羥-(C2-4)-烷基、及硝基所組成之組群,或R1及R2與吡啶核之二接續碳原子共同形成一個視需要可經以一個或二個甲基或乙基取代之苯環,及R3為羥烷基(C1-4)。此外,說明獲得此等化合物之方法。此等化合物具有抗菌活性。