4-11-00-00250 (Beilstein Handbook Reference) 778-28-9 AI3-02551 BRN 1428508 Benzenesulfonic acid, 4-methyl-, butyl ester Butyl 4-methylbenzenesulfonate Butyl p-methylbenzenesulfonate Butyl p-toluenesulfonate Butyl toluene-4-sulphonate Butyl tosylate Butyl-p-toluenesulfonate EINECS 212-295-5 NSC 6190 n-Butyl p-toluenesulfonate p-TOLUENESULFONIC ACID, BUTYL ESTER p-Toluene sulfonic acid, butyl ester