4-Amino-3-methylbenzenesulfonic acid98-33-931 % similar p-Toluenesulfonic acid monohydrate6192-52-530 % similar 3,4-Diaminobenzenesulfonic acid7474-78-430 % similar Naphthalene-1-sulfonic acid85-47-230 % similar 4-Ethylbenzenesulfonic acid98-69-130 % similar Flavianic acid483-84-130 % similar 4-Pyridinesulphonic acid5402-20-030 % similar Armstrong's acid81-04-930 % similar S Acid83-64-730 % similar