2(3H)-Benzothiazolone, 3-methyl-, hydrazone, monohydrochloride 2-Benzothiazolinone, 3-methyl-, hydrazone, monohydrochloride 3-Methyl-2-benzothiazolinone hydrazone hydrochloride 4338-98-1 MBTH hydrochloride NSC65901