CGP 4832

CGP 4832 is a semisynthetic derivative of rifamycin S, classified as a naphthofuran compound. It was developed to enhance antibacterial activity, particularly against Gram-negative bacteria. Compared to rifampicin, CGP 4832 demonstrates significantly higher potency—up to 400 times lower minimum inhibitory concentrations (MICs) against certain Gram-negative strains. Its mechanism of action involves inhibition of DNA-dependent RNA polymerase (DNA-directed RNA polymerase), similar to other rifamycins, thereby blocking bacterial transcription. The increased efficacy is attributed not to a difference in enzyme inhibition but likely due to improved penetration into bacterial cells via specific uptake mechanisms[1][2][3][5].