Antitubercular agent-56 

Antitubercular agent-56, a Questiomycin A (HY-N8439) derivative, is a potent and orally active antitubercular agent. Antitubercular agent-56 disrupts mycobacterial envelope integrity by inhibiting FabD (K_d = 9.39 μM; IC₅₀ = 49.60 μM). Antitubercular agent-56 exhibits good intracellular antimycobacterial activity against Mycobacterium tuberculosis (MTB) and drug-resistant MTB both in vitro and in vivo. Antitubercular agent-56 can be used for research on tuberculosis (TB)^[1].

Antitubercular agent-56 (compound B10) (7 days) exhibits potent antitubercular activity against MTB H₃₇Rv (MIC = 0.15 μg/mL) and drug-sensitive and drug-resistant MTB strains with MIC range from 0.063 to 0.25 μg/mL)^[1].
Antitubercular agent-56 (0.26-64 μg/mL, 48 h) exhibits low cytotoxicity against Vero, HepG2 and J774A.1 cells with IC₅₀s of >128, >80, and >80 μg/mL, respectively^[1].
Antitubercular agent-56 (1/2 × MIC-16 × MIC; 0-14 days) exhibits potent bactericidal efficacy against H₃₇Rv MTB strain and clinical isolate in a concentration- and time-dependent manner^[1].
Antitubercular agent-56 (1-4 μg/mL; 72 h) effectively penetrates macrophages and inhibits intracellular MTB growth^[1].
Antitubercular agent-56 (4 × MIC; 30 min) significantly increases mycobacterial membrane permeability compared to control, confirming its disruptive effect on cell wall integrity^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Antitubercular agent-56 (compound B10) (100 mg/kg; i.g.; five times weekly for 3 weeks) reduces lung bacterial burden in mice infected with tuberculosis^[1].
Antitubercular agent-56 (500 mg/kg; i.g.; single dose) exhibits a favorable safety profile in mice^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

295.29

C₁₆H₁₃N₃O₃

O=C1C(NC(NC2CC2)=O)=CC3=NC4=C(OC3=C1)C=CC=C4

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Xu M, et al. Discovery and Optimization of Phenoxazinone Derivatives as Potent Antitubercular Agents Targeting FabD Protein. J Med Chem. 2026;69(1):163-182.  [Content Brief]