In organic chemistry, brosyl (or para-bromophenylsulfonyl) group is a functional group with the chemical formula BrCHSO. This group is usually introduced using the compound brosyl chloride, BrCHSOCl, which forms sulfonyl esters and amides of p-bromophenylsulfonic acid. The term brosylate refers to the anion of p-bromophenylsulfonic acid (BrCHSO).