2-Nitropyridine → HCID 68598513, compound

Participants

Reaction Steps

To a 10 mL round-bottomed flask were added (1R)-1-[(4-amino-1-piperidinyl)methyl]-1,2-dihydro-4H,9H-imidazo[1,2,3-ij]-1,8-naphthyridine-4,9-dione dihydrochloride (for a preparation see Example 5A(j)) (75 mg, 0.223 mmol), 7-chloro-3,4-dihydro-2H-pyrido[3,2-b][1,4]thiazine-6-carbaldehyde (prepared by (1) reduction of 7-chloro-3-oxo-3,4-dihydro-2H-pyrido[3,2-b][1,4]thiazine-6-carbaldehyde (for a synthesis see WO2003087098 Example 306(e)) with LiAlH4 to give (7-chloro-3,4-dihydro-2H-pyrido[3,2-b][1,4]thiazin-6-yl)methanol and then (2) oxidation with MnO2)) (47.8 mg, 0.223 mmol), and NaHCO3 (100 mg, 1.190 mmol) in DCM (4 ml) and methanol (1 ml) to give a brown suspension. Sodium sulfate (200 mg, 1.408 mmol) was added and the reaction was allowed to stir at rt overnight. After 15 h sodium triacetoxyborohydride (94 mg, 0.445 mmol) was added and the reaction was allowed to stir at 25° C. under nitrogen for 4 h. The reaction mixture was adsorbed onto silica and purified using 0-10% MeOH/DCM (1% NH4OH) to give the title compound as a free base (45 mg, 0.090 mmol, 40.5% yield). LCMS & 1H NMR were consistent with the desired product.

Provenance & Evidence