DC 107 derivatives represented by general formula (I) or pharmacologically acceptable salts thereof, each having antibacterial and antitumor activities, wherein R1 represents hydrogen, lower alkoxyalkyl, aralkyloxyalkyl, lower alkoxyalkoxyalkyl, lower alkoxyalkoxyalkoxyalkyl, aralkyl, tetrahydropyranyl, COR4, etc.; R2 represents hydrogen or COR6; R3 represents -CH¿2COOR?7, phthalimidomethyl, etc.; and W represents oxygen or NR8 (wherein R8 represents hydroxy, lower alkoxy, lower alkenyloxy, aralkyloxy, optionally substituted arylsulfonylamino or lower alkoxycarbonylamino).