Molecular Formula: C6H6NNaO3S Molecular Weight: 195.17 Properties: White crystals. Highly soluble in water; insoluble in ethanol, ether, and benzene. Preparation Method: Obtained by sulfonation and rearrangement of aniline. Uses: Intermediate for dyes, used in Acid Orange II, Acid Light Yellow 2G, Acid Mordant Yellow Brown 4G, Acid Mordant Deep Yellow GG, Direct Yellow GR, Reactive Yellow K-RN, Brilliant Red K-10B, Brilliant Red K-2G, Claret K-DG, and Violet K-3R, among others. Also used in the production of dyeing auxiliaries such as Dissolving Salt B, Fluorescent Brightener BG, and Anti-staining Agent H. Extensively used as a pesticide to control wheat rust.
　A fungicide. Primarily used to control wheat rust and rust diseases in other crops. For controlling rust in wheat, spray with a 250-fold dilution of the raw chemical when the disease appears in spots or patches and the overall greenness significantly increases. Apply every 7–10 days, for a total of 2–3 times. Adding 0.05 kg of laundry detergent per 50 kg of spray solution can improve adhesion and increase control efficacy. For controlling rust in broad beans and peas, spray with a 300-fold dilution of the raw chemical every 7–10 days.