12H-1,2,4-Triazolo(4',3':1,6)pyridazino(4,5-b)(1,4)benzothiazine, 3-(ethylthio)- 3-(Ethylthio)-12H-1,2,4-triazolo(4',3':1,6)pyridazino(4,5-b)(1,4)benzothiazine 92115-90-7