[Br:1][C:2]1[C:3](Cl)=[N:4][C:5]2[C:10]([CH:11]=1)=[CH:9][CH:8]=[CH:7][CH:6]=2.[N:13]1(C=O)[CH2:18][CH2:17][NH:16][CH2:15][CH2:14]1.[N+:21]([O-])([OH:23])=[O:22]>C([O-])(O)=O.[Na+].C1COCC1.OS(O)(=O)=O.[OH-].[Na+]>[Br:1][C:2]1[C:3]([N:13]2[CH2:18][CH2:17][NH:16][CH2:15][CH2:14]2)=[N:4][C:5]2[C:10]([CH:11]=1)=[CH:9][C:8]([N+:21]([O-:23])=[O:22])=[CH:7][CH:6]=2A stirred mixture of 7 (200 mg, 0.83 mmol) and 1-Piperazinecarboxaldehyde (4 ml) was heated at 120° C. for 15 min. under argon. The mixture was then cooled and diluted with 0.5M NaHCO3. The aqueous phase was extracted with ether (3×) and the combined extractions were dried (MgSO4). Concentration yielded a residue which was immediately dissolved in THF (10 ml) and 4M H2SO4 (5 ml). The solution was then brought to reflux and stirred for 1 h. The solution was cooled and poured into 1M NaOH. The resulting suspension was then extracted twice with ether and the ether extracts were dried (MgSO4). Evaporation of the solvent afforded a material which was immediately dissolved in H2SO4 (5 ml). To this solution was added dropwise HNO3 (0.1 ml) at -10° C. The mixture was stirred 15 min. at -10° -0° C., poured onto ice, and diluted with 1M NaOH until basic. The mixture was then extracted with CH2C2 (3×), and the combined organic layers were dried (MgSO4). Concentration yielded the quipazine analogue 1 (189 mg, 68% based on 7). 1H NMR d (ppm): 1.9 br (NH), 3.1 dd (CH2), 3.5 dd (CH2), 7.8 d (CH arom), 8.3 s (CH arom), 8.3 d (CH arom), 8.5 s (CH arom).
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