Premise: Phenazine is an organic compound with the formula (CH)N. It is a dibenzo annulated pyrazine, and the parent substance of many dyestuffs, such as the toluylene red, indulines, and safranines (and the closely related eurhodines). Phenazine crystallizes in yellow needles, which are only sparingly soluble in alcohol. Sulfuric acid dissolves it, forming a deep-red solution.
Hypothesis: Phenazine is the parent substance of many dyestuffs and can be dissolved in sulfuric acid.