N[C:2]1[C:7]([N+:8]([O-:10])=[O:9])=[CH:6][C:5]([Cl:11])=[CH:4][N:3]=1.Br[C:13]1[C:18]([N+:19]([O-:21])=[O:20])=[CH:17][C:16]([Cl:22])=[CH:15][N:14]=1.I([O-])(=O)(=O)=O.[Na+].[OH2:29]>C1COCC1.[Os](=O)(=O)(=O)=O>[Cl:11][C:5]1[CH:6]=[C:7]([N+:8]([O-:10])=[O:9])[C:2]([CH:13]=[O:29])=[N:3][CH:4]=1.[Cl:22][C:16]1[CH:17]=[C:18]([N+:19]([O-:21])=[O:20])[C:13]([CH:2]=[CH2:7])=[N:14][CH:15]=12-Amino-3-(6-chloro-3-methoxy-2H-pyrazolo[4,3-b]pyridin-2-yl)-2-methylpropionitrile (39 mg) was prepared quantitatively using a procedure similar to that described in Example 1, part b, except starting from 1-(6-chloro-3-methoxy-2H-pyrazolo[4,3-b]pyridin-2-yl)propan-2-one (32 mg). 1-(6-Chloro-3-methoxy-2H-pyrazolo[4,3-b]pyridin-2-yl)propan-2-one was prepared using a procedure similar to that described in Example 105 part a to d except using 5-chloro-3-nitropyridine-2-carboxaldehyde (1.2 g) and decaborane in part a to yield [2-(tert-butyldimethylsilanyloxy)propyl]-(5-chloro-3-nitropyridin-2-yl-methyl)amine (0.4 g, 17%). 5-Chloro-3-nitropyridine-2-carboxaldehyde was prepared using a procedure similar to that described in Example 136 part a to c except starting from 2-amino-5-chloro-3-nitropyridine in part a or using commercially available 2-bromo-5-chloro-3-nitropyridine in part b. Alternatively, oxidative cleavage using a 4% solution of osmium tetroxide in water (2 mL) and sodium periodate (1.2 g) was carried out in a mixture of THF and water (10:1, 20 mL) in part c instead of ozonolysis following a procedure similar to that described in Example 61 to afford 5-chloro-3-nitropyridine-2-carboxaldehyde (0.72 g, 72%) from 5-chloro-3-nitro-2-vinylpyridine (1 g).
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