ANTIBACTERIAL OLIGOMER AND ANTIBACTERIAL AGENT

PROBLEM TO BE SOLVED: To obtain an oligomer having antibacterial action on bacteria, especially Gram-positive bacteria, above all such as vancomycin resistant Enterococcus and methicillin resistant Staphylococcus aureus by introducing a chemical structure of an antibiotic to a side chain of each repeating unit and arranging the average degree of polymerization in a predetermined range. SOLUTION: This oligomer has a chemical structure of an antibiotic such as vancomycin, teicoplanin, ristocetin A or eremomycin, or the like, in each repeating unit, for example, expressed by the formula ((n) is an integer of 0-10; (m) is an integer of 2-60), has 2-30 of average degree of polymerization, and exhibits active antibacterial action on bacteria exhibiting resistance to the antibiotics. The formulating amount of the antibacterial oligomer in a pharmaceutical preparation is 0.2-10 wt.%, and preferably administered at a daily dose of 1-1,000 mg for an adult.