[C:1]([NH:4][C:5]1[CH:13]=[CH:12][C:8]([C:9](O)=[O:10])=[CH:7][N:6]=1)(=[O:3])[CH3:2].NC1C=CC(C(O)=O)=CN=1.CN1CCOCC1.ClC(OCC)=O.[H-].[Al+3].[Li+].[H-].[H-].[H-].[OH-].[Na+]>C1COCC1.O>[OH:10][CH2:9][C:8]1[CH:12]=[CH:13][C:5]([NH:4][C:1](=[O:3])[CH3:2])=[N:6][CH:7]=1A solution of 219 mg (1.22 mmol) of 6-(acetylamino)nicotinic acid [preparable from 6-aminonicotinic acid according to A. Zafar et al., Tetrahedron 56, 8419-8428 (2000)] in 25.4 ml of dry THF is cooled to −10° C., and 123 mg (1.22 mmol) of 4-methylmorpholine and 132 mg (1.22 mmol) of ethyl chloroformate are added dropwise with stirring. The reaction solution is stirred at −10° C. for 30 min 2.44 ml (2.44 mmol) of a 1 M solution of lithium aluminium hydride and THF are then added dropwise. The reaction mixture is stirred for 8 h and slowly warmed to RT during this time. The reaction solution is then cooled to 0° C., 0.4 ml of water and 0.8 ml of 1 N aqueous sodium hydroxide solution are added carefully and, after warming to RT, the mixture is stirred at this temperature for 8 h. The mixture is filtered and the filtrate is concentrated on a rotary evaporator. The crude product that remains is used for the subsequent reaction without further purification.
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