ethyl 2-[2-aminoethyl(methyl)amino]acetate;dihydrochloride

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

Procedure: Concentrated hydrochloric acid (10 ml) was added to a solution of ethyl 2-((2-((tert-butoxycarbonyl)amino)ethyl)(methyl)amino)acetate (intermediate 83, 3.05 g, 11.13 mmol) in THF (20 ml) and EtOH (100 ml) at room temperature. After stirring 1 h at room temperature the reaction mixture was evaporated, ethanol (20 ml) added, evaporated, further ethanol (50 ml) added and then stirred at 60° C. for 70 min. The cooled reaction mixture was then evaporated to give the title compound as a pale-yellow glass. 1H NMR (400 MHz, DMSO-d6) δ 8.58 (s, br, 3H), 4.19 (q, 2H), 4.26-4.15 (m, 2H), 3.44 (s, br, 2H), 3.21 (s, br, 2H), 2.88 (s, 3H), 1.21 (t, 3H). was evaporated ethanol (20 ml) added evaporated further ethanol (50 ml) added stirred at 60° C. for 70 min The cooled reaction mixture was then evaporated

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

Procedure: Sodium triacetoxyborohydride (3.10 g, 14.61 mmol) was added to a mixture of 2-(dimethoxymethyl)-5,6,7,8-tetrahydro-1,8-naphthyridine-3-carbaldehyde (intermediate 41, 2.30 g, 9.74 mmol), ethyl 2-((2-aminoethyl)(methyl)amino)acetate dihydrochloride (intermediate 82, 2.6 g, 14.61 mmol) and triethylamine (6.75 ml, 48.7 mmol) in 1,2-dichloroethane (20 ml) at room temperature. The reaction mixture was stirred for 21 h at room temperature and additional sodium triacetoxyborohydride (2.6 g, 9.74 mmol) was added. After a further 4 h stirring at room temperature, again additional sodium triacetoxyborohydride (1.3 g, 4.87 mmol) was added and the reaction maintained at 4° C. for 2.5 days. The reaction mixture was then warmed to room temperature, saturated aqueous NaHCO3 solution added, the mixture extracted with DCM (3×), the combined organic layers dried over Na2SO4 and evaporated. The residue was applied to a 120 g RediSep® silica column as a DCM solution and purified by normal phase chromatography, eluting with a gradient from DCM to 10% MeOH in DCM. Product containing fractions were combined and evaporated to give the title compound as an orange foam. 1H NMR (400 MHz, CDCl3) δ 7.08 (s, 1H), 5.30 (s, br, 1H), 5.20 (s, 1H), 4.69 (s, 2H), 3.44-3.34 (m, 2H), 3.40 (s, 6H), 3.22-3.15 (m, 2H), 3.24 (s, 2H), 2.71-2.64 (m, 2H), 2.58-2.50 (m, 2H), 2.31 (s, 3H), 1.98-1.82 (m, 2H). (UPLC-MS 6) tR 0.33; ESI-MS 335.3 [M+H]+. After a further 4 h stirring at room temperature the reaction maintained at 4° C. for 2.5 days The reaction mixture was then warmed to room temperature the mixture extracted with DCM (3×) the combined organic layers dried over Na2SO4 evaporated purified by normal phase chromatography eluting with a gradient from DCM to 10% MeOH in DCM Product containing fractions evaporated