2,4-Dimethyl-pyrimido(2,1-b)benzothiazol-5-ium perchlorate 2,4-Dimethyl-pyrimido(2,1-b)benzothiazole perchlorate 28737-68-0 Pyrimido(2,1-b)benzothiazol-5-ium, 2,4-dimethyl-, perchlorate