7H-​Pyrazolo[4,​3-​d]​pyrimidine-​7-​thione, 1,​6-​dihydro-​1-​methyl-​5-​[5-​[(4-​methyl-​1-​piperazinyl)​sulfonyl]​-​2-​propoxyphenyl]​-​3-​propyl-