Antibacterial and inducer activities of thirteen TC derivatives were investigated for tetracycline (TC) resistance in staphylococcus aureus. Four compounds of the TC derivatives were not able to induce the resistance to TC in Staphylococcus aureus MS3937 rms7 (TC)+ harboring an inducible TC resistance determinant located on a plasmid. The 12a-hydroxy position seems to be essential for the inducer activity.
