[NH2:1][C:2]1[C:3]([C:9]([OH:11])=O)=[N:4][CH:5]=[C:6]([CH3:8])[N:7]=1.C([N:15]([CH:18](C)C)CC)(C)C.CCN=C=NCCCN(C)C.Cl.C1C=CC2N(O)N=NC=2C=1.Cl.[CH3:44][O:45]NOOC>CN(C=O)C>[CH3:44][O:45][N:15]([CH3:18])[C:9]([C:3]1[C:2]([NH2:1])=[N:7][C:6]([CH3:8])=[CH:5][N:4]=1)=[O:11]3-Amino-5-methyl-pyrazin-2-carboxylic acid (0.48 g, 3.12 mmol) is dissolved in anhydrous DMF (10 ml) under N2. The brown solution is cooled to 0° C., and diisopropylethylamine (1.48 ml, 7.9 mmol), EDC.HCl (0.75 g, 3.8 mmol), HOBt (0.58 g, 3.8 mmol) and N,O-dimethoxyhydroxylamine hydrochloride (0.37 g, 3.8 mmol) are added and the reaction is stirred at 0° C. for 1 hour and at room temperature for 4 hours. The solvent is concentrated in vacuo, and the residue is diluted with EtOAc and aq. NaHCO3. The phases are separated and the aqueous layer washed with EtOAc. The organic layers are combined, washed with brine, dried (MgSO4) and concentrated in vacuo. Purification by flash chromatography (SiO2, 0-5% MeOH in DCM) yields 3-amino-5-methyl-pyrazin-2-carboylic acid methoxy-methyl-amide as a pale yellow solid. [M+H]+ 197.
読み込み中…
