Fractionation of BMS-824 incubated in medium. BMS-824 was incubated in medium for 48 h and then subjected to extraction with acetonitrile and chloroform, followed by preparative HPLC. The six key peaks identified are labeled P1 to P6. Assignment of peak components indicated: P1, thiourea; P2, oxidized BMS-824; P3, BMS-824. Other peaks did not contain enough material for structure determination. Abs., absorbance.