A pharmaceutical composition comprising a pharmaceutically acceptableexcipient and a compound of formula (I): wherein R1, R2 and R3 at eachoccurrence are independently selected from amino, aminosulfinyl,aminosulfonyl, aryl, azido, halogen, heteroalkyl, heteroaryl, hydrazinyl,hydrocarbyl, hydrogen, hydroxyl, nitro, nitroso, phosphate, phosphinate,phosphonate, phosphonium, phosphorothioate, phosphoryl, sulfamoyl, sulfate,sulfinic acid, sulfonamido, sulfonate, sulfonic acid, sulfonyl, sulfoxido,thiol, thioureido, and ureido, and R4 is selected from hydrogen, heteroalkyl,heteroaryl, and hydrocarbyl is described as useful in treatment of disordersassociated with dysregulation of cell proliferation.
