[Cl:1][C:2]1[CH:3]=[C:4]([NH:9][C:10]2[C:11]([C:18]([OH:20])=O)=[CH:12][N:13]([CH3:17])[C:14](=[O:16])[CH:15]=2)[CH:5]=[CH:6][C:7]=1[Cl:8].N.C1C[N:25]([P+](ON2N=NC3C=CC=CC2=3)(N2CCCC2)N2CCCC2)CC1.F[P-](F)(F)(F)(F)F>ClCCl>[Cl:1][C:2]1[CH:3]=[C:4]([NH:9][C:10]2[C:11]([C:18]([NH2:25])=[O:20])=[CH:12][N:13]([CH3:17])[C:14](=[O:16])[CH:15]=2)[CH:5]=[CH:6][C:7]=1[Cl:8]The product of step A (234 mg) was dissolved in dichloromethane (5 mL) and ethanolic ammonia (2 M, 2.0 mL, 4.0 mmol): PyBOP (579 mg, 1.10 mmol) was added in one portion and the reaction mixture was stirred overnight at ambient temperature. The reaction mixture was quenched with acetic acid (ca. 0.5 mL), diluted with ethyl acetate (40 mL) and washed with water (2×10 mL) and saturated brine (10 mL). The organics were dried over magnesium sulfate, concentrated in vacuo and chromatographed on silica gel. Elution with dichloromethane-methanol (4:1) afforded 4-(3,4-Dichloro-phenylamino)-1-methyl-6-oxo-1,6-dihydro-pyridine-3-carboxylic acid amide (28 mg, 12% yield) as a dark yellow-colored solid. An analytical sample was prepared by crystallization from methanol: m.p. >250° C.; 1H NMR (DMSO-d6, 400 MHz) δ10.38 (s, 1H), 8.30 (s, 1H), 7.85 (br s, 1H), 7.57 (d, J=8.8 Hz, 1H), 7.48 (d, J=2.4 Hz, 1H), 7.45 (br s, 1H), 7.23 (dd, J=8.8, 2.4 Hz, 1H), 5.70 (s, 1H), 3.33 (s, 3H). Anal. Calcd./Found for C13H11Cl2N3O2: C, 50.02/50.02; H, 3.55/3.19; N, 13.46/13.21.
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