N-methylethanesulfonamide

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 480 mg (3.5 mmol) of N-methylethylsulfonamide in 0.75 ml DMSO (dimethylsulfoxide) is added to a suspension of 27 mg (0.7 mmol) of NaH (60% strength) in 1.5 ml of DMSO. After stirring at room temperature for 2 h, a solution of 0.48 g (2.7 mmol) of 2,2-dimethyl-1a,7b-dihydro-2H-1,3-dioxa-6-aza-cyclo-propa[a]naphthalene (prepared analogously to G. Burell et al. J. Med. Chem. 33 (1990) 3023-3027) in 6 ml of DMSO is added dropwise. The mixture is heated at 60° C. for 4 h and then stirred overnight at room temperature. The reaction mixture is added to ice water and extracted with ethyl acetate. After removing the solvent in vacuo, the solid obtained is stirred with a mixture of heptane and ethyl acetate and filtered off with suction. 400 mg (67%) of ethanesulfonic acid (3-hydroxy-2,2-dimethyl-3,4-dihydro-2H-pyrano[3,2-c]pyridin-4-yl)methylamide are obtained as a solid (m.p. 163° C.). The mixture is heated at 60° C. for 4 h stirred overnight at room temperature extracted with ethyl acetate After removing the solvent in vacuo the solid obtained filtered off with suction

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:118.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a dried sealable pressure tube flushed with argon was placed methyl 5-bromo-8-{[(4-methylphenyl)sulfonyl]oxy}-1,6-naphthyridine-7-carboxylate (2.0 g, 4.57 mmol), prepared as described in Example 2, Step 2), N-methylethanesulfonamide (1.13 g, 9.15 mmol), dry DMF (4 mL) and copper(I) oxide (785 mg, 5.49 mmol) and 2,2′ bipyridyl (857 mg, 5.49 mmol). The tube was capped and heated to 118° C. for 2 hours. The reaction was cooled and filtered through a glass fiber filter, washing with chloroform. The filtrate was diluted with chloroform (about 100 mL total volume) and stirred with an EDTA solution (5 g EDTA in 100 mL water) for two hours or until the aqueous layer became aqua in color and the organic layer became yellow. The layers were separated and the aqueous layer was extracted twice more with chloroform. The combined organic extracts were dried over sodium sulfate, filtered, and concentrated under reduced pressure. The residue was redissolved in 2 mL of DMSO and purified by preparative HPLC (Gilson semi preparative HPLC system using a Waters Nova pak column (10×40 mm I.D. cartridges, C18, 6 μM pore size) eluting with 95-5% water (0.025% TfEA)/acetonitrile (0.025% TFA) at 35 mLjmin) and the desired fractions were freeze dried to give the product as a yellow powder. In a dried sealable pressure tube flushed with argon prepared The tube was capped The reaction was cooled filtered through a glass fiber filter washing with chloroform The filtrate was diluted with chloroform (about 100 mL total volume) The layers were separated the aqueous layer was extracted twice more with chloroform The combined organic extracts were dried over sodium sulfate filtered concentrated under reduced pressure The residue was redissolved in 2 mL of DMSO purified by preparative HPLC (Gilson semi preparative HPLC system eluting with 95-5% water (0.025% TfEA)/acetonitrile (0.025% TFA) at 35 mLjmin) and the desired fractions dried

Conditions: temp:118.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a dried sealable pressure tube flushed with argon was placed methyl 5-bromo-8-{[(4-methylphenyl)sulfonyl]oxy}-1,6-naphthyridine-7-carboxylate (2.0 g, 4.57 mmol), prepared as described in Example 2, Step 2), N-methylethanesulfonamide (1.13 g, 9.15 mmol), dry DMF (4 mL) and copper(I) oxide (785 mg, 5.49 mmol) and 2,2′ bipyridyl (857 mg, 5.49 mmol). The tube was capped and heated to 118° C. for 2 hours. The reaction was cooled and filtered through a glass fiber filter, washing with chloroform. The filtrate was diluted with chloroform (about 100 mL total volume) and stirred with an EDTA solution (5 g EDTA in 100 mL water) for two hours or until the aqueous layer became aqua in color and the organic layer became yellow. The layers were separated and the aqueous layer was extracted twice more with chloroform. The combined organic extracts were dried over sodium sulfate, filtered, and concentrated under reduced pressure. The residue was redissolved in 2 mL of DMSO and purified by preparative HPLC (Gilson semi preparative HPLC system using a Waters Nova pak column (10×40 mm I.D. cartridges, C18, 6 μM pore size) eluting with 95-5% water (0.025% TfEA)/acetonitrile (0.025% TFA) at 35 mLjmin) and the desired fractions were freeze dried to give the product as a yellow powder. In a dried sealable pressure tube flushed with argon prepared The tube was capped The reaction was cooled filtered through a glass fiber filter washing with chloroform The filtrate was diluted with chloroform (about 100 mL total volume) The layers were separated the aqueous layer was extracted twice more with chloroform The combined organic extracts were dried over sodium sulfate filtered concentrated under reduced pressure The residue was redissolved in 2 mL of DMSO purified by preparative HPLC (Gilson semi preparative HPLC system eluting with 95-5% water (0.025% TfEA)/acetonitrile (0.025% TFA) at 35 mLjmin) and the desired fractions dried

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 480 mg (3.5 mmol) of N-methylethylsulfonamide in 0.75 ml DMSO (dimethylsulfoxide) is added to a suspension of 27 mg (0.7 mmol) of NaH (60% strength) in 1.5 ml of DMSO. After stirring at room temperature for 2 h, a solution of 0.48 g (2.7 mmol) of 2,2-dimethyl-1a,7b-dihydro-2H-1,3-dioxa-6-aza-cyclo-propa[a]naphthalene (prepared analogously to G. Burell et al. J. Med. Chem. 33 (1990) 3023-3027) in 6 ml of DMSO is added dropwise. The mixture is heated at 60° C. for 4 h and then stirred overnight at room temperature. The reaction mixture is added to ice water and extracted with ethyl acetate. After removing the solvent in vacuo, the solid obtained is stirred with a mixture of heptane and ethyl acetate and filtered off with suction. 400 mg (67%) of ethanesulfonic acid (3-hydroxy-2,2-dimethyl-3,4-dihydro-2H-pyrano[3,2-c]pyridin-4-yl)methylamide are obtained as a solid (m.p. 163° C.). The mixture is heated at 60° C. for 4 h stirred overnight at room temperature extracted with ethyl acetate After removing the solvent in vacuo the solid obtained filtered off with suction