Netilmicin drug molecule. Ball-and-stick molecular model of netilmicin, an aminoglycoside antibiotic. It is a derivative of sisomicin, and is able to kill a wide range of bacteria. However, it is only used in the treatment of serious infections, particularly those caused by bacteria resistant to gentamicin. Its chemical formula is C21H41N5O7. Atoms are represented as spheres with conventional colour coding: hydrogen (white), carbon (black), oxygen (red), and nitrogen (blue).