[Br:1][C:2]1[CH:11]=[C:10]2[C:5]([CH:6]=[CH:7][C:8](Cl)=[N:9]2)=[CH:4][CH:3]=1.[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[CH:11]=[C:10]2[C:5]([CH:6]=[CH:7][C:8]([N:13]3[CH2:18][CH2:17][NH:16][CH2:15][CH2:14]3)=[N:9]2)=[CH:4][C:3]=1[N+:21]([O-:23])=[O:22]A stirred mixture of 19 (70 mg, 0.29 mmol) and 1-Piperazinecarboxaldehyde (4 ml) was heated at 125° C. for 30 min. under argon. The mixture was then cooled and diluted with saturated aqueous 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 CH2Cl2 (3×), and the combined organic layers were dried (MgSO4). Concentration yielded the quipazine analogue 3 (47 mg, 48% from 19). 1H NMR d (ppm): 1.60 s (NH), 3.00 dd (CH2), 3.80 dd (CH2), 7.04 d (CH arom), 7.87 d (CH arom), 7.95 s (CH arom), 8.24 s (CH arom).
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