Allowing it to stand for 20 min, followed by filtration, resulted in the third compound in a pure form of N-(3,5-dichloro-2-ethoxy-6-fluoropyridin-4-yl)-3-oxobutanamide(3). The mixture of allowing it to stand for 20 min, followed by filtration, resulted in the third compound in a pure form of N-(3,5-dichloro-2-ethoxy-6-fluoropyridin-4-yl)-3-oxobutanamide(3) Transmembrane Transporters modulator (0.005 M), urea/thiourea (0.0075 M), and appropriate aldehyde (0.005 M) with catalytic amount of PTSA in 10 ml of ethanol was stirred for 18–26 h. The reactions were monitored through TLC using 30% ethyl acetate in pet ether as solvent system. After the reaction was complete, the reaction mixture was cooled in a refrigerator and filtered. The precipitate obtained was washed

thoroughly with water to remove unreacted urea/thiourea and dried. The crude solid product was recrystallized with ethanol to give the pure compounds (7a–k) Staurosporine clinical trial Scheme 1. Colorless crystalline solid, M.P: 162–164 °C, Yield – 52%, IR (KBr, cm−1): 3254 (N–H), 3036 (Ht–ArC–H), 2856 (AliC–H), 1734 (C O, ketone), 1646 (C O, amide), 1542 (C C), 1356 (C–N), 658 (C–F), 1H NMR (DMSO-d6) d: 2.31 (s, 3H, CH3), 3.48 (s, 2H, CH2), 7.26 (d, 2H, ArH), 7.46 (d, very 2H, ArH), 9.36 (s, 1H, NH), MS (m/z): M+ calculated 195.19, found, 194.86. Pale-yellowish solid, M.P: 245–247 °C, Reaction time – 23 h, Yield – 52%, IR (KBr, cm−1): 3260 (N–H), 3172(ArC–H), 2960 (AliC–H), 1680 (C O, amide), 1534 (C C), 1190 (O–C), 1H NMR (DMSO-d6) d: 2.04 (s, 3H, CH3), 3.42 (s, 5H, OC2H5), 5.36 (s, 1H, CH), 6.48–6.81 (d, 2H, ArH), 7.29–7.37 (m, 5H, ArH), 7.48 (d, 2H, ArH), 8.68 (s, 1H, NH), 8.86 (s, 1H, NH), 9.38 (s, 1H, NH). MS (m/z): M+ calculated 439.06, found 438.96. Light-bluish colored solid, M.P: 272–274 °C,

Reaction time – 22 h, Yield – 57%, IR (KBr, cm−1): 3276 (N–H), 3143(ArC–H), 2964 (AliC–H), 1676 (C O, amide), 1564 (C C), 1168 (O–C), 1H NMR (DMSO-d6) d: 2.02 (s, 3H, CH3), 3.52 (d, 5H, OC2H5), 5.74(s, 1H, CH), 6.52 (d, 2H, ArH), 7.34–7.48 (m, 5H, ArH), 7.74 (d, 2H, ArH), 9.24 (s, 1H, NH), 9.65 (s, 1H, NH), 9.88 (s, 1H, NH), MS (m/z): M+ calculated 353, found 353.75. MS (m/z): M+ calculated 455.03, found 455.09. Light-greenish colored solid, M.P: 238–240 °C, Reaction time – 25 h, Yield – 48%, IR (KBr, cm−1): 3356 (N–H), 3148 (ArC–H), 2974 (AliC–H), 1694 (C O, amide), 1557 (C C), 1310 (O–C), 1H NMR (DMSO-d6) d: 2.01 (s, 3H, CH3), 3.62 (d, 5H, OC2H5), 5.48 (s, 1H, CH),6.76 (d, 2H, ArH), 6.78–7.19 (m, 4H, ArH), 7.42 (d, 2H, ArH), 7.54 (s, 1H, NH), 8.56 (s, 1H, NH), 9.32 (s, 1H, NH). MS (m/z): M+ calculated 483.05, found 482.96.