Questiomycin A is a phenoxazine produced by several Streptomyces species and some fungi and bacteria. Questiomycin A is weakly active against bacteria, fungi, plants and tumor cell lines, and inhibits aromatase and sulfatases. More recently, questiomycin A has been shown to inhibit pulmonary metastasis caused by mouse melanoma cells. Questiomycin A and related phenoxazines are important dereplication standards in discovery research to eliminate leads due to high amounts of weakly potent actives.
Questiomycin A is soluble in ethanol, methanol, DMF and DMSO.
Questiomycin A is soluble in ethanol, methanol, DMF and DMSO.