Questiomycin A

Questiomycin A is a phenoxazine and a chromophore that has been found in Streptomyces and has antibacterial and anticancer activities. It is active against M. scrofulaceum, M. marinum, and M. intracellulare (MICs = 2.8, 11.3, and 5.6 µg/ml, respectively) but not M. tuberculosis, M. smegmatis, M. kansasii, or M. fortuitum (MICs = >45 µg/ml). It is also inactive against E. coli, P. aeruginosa, S. tymphimurium, S. aureus, or L. monocytogenes. It is cytotoxic to a variety of cancer cells, including MCF-7, A549, MIA PaCa-2, and LoVo-1 cells (IC50s = 1.67, 5.48, 7.16, and 20.03 µM, respectively) as well as human umbilical vein endothelial cells (HUVECs) but not human embryonic lung fibroblast cells (HELs, IC50s = 16.06 and >50 µM, respectively). Questiomycin A reduces the increased intracellular pH in a variety of cancer cell lines, as well as in HUVECs and HELs. It prevents lung metastasis in a B16 mouse melanoma model of metastasis when administered at a dose of 0.5 mg/kg simultaneously with B16 cells or every three days. It is also a chromophore product of the reducing agent 2-aminophenol oxidation (as 2-amino-phenoxazine-3-one) and has been used as a readout in the study of catalytic oxidation of 2-aminophenol by various metal-containing complexes. It has an absorbance of 435 nm in methanol.Formal Name: 2-amino-3H-phenoxazin-3-one. CAS Number: 1916-59-2. Molecular Formula: C12H8N2O2. Formula Weight: 212.2. Purity: >98%. Formulation: (Request formulation change), A solid. Solubility: DMF: 2mg/mL, DMSO: 3mg/mL, DMSO:PBS (pH 7.2) (1:20): 0.04mg/mL. lambdamax: 239, 433 nm. SMILES: NC1=CC2=NC3=CC=CC=C3OC2=CC1=O. InChi Code: InChI=1S/C12H8N2O2/c13-7-5-9-12(6-10(7)15)16-11-4-2-1-3-8(11)14-9/h1-6H,13H2. InChi Key: RDJXPXHQENRCNG-UHFFFAOYSA-N. Origin: Synthetic.