1-methylpiperidine-2,4-dione

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

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a 50-mL round bottomed flask was added ethanol (4 mL) under argon, followed by sodium (0.121 g, 5.25 mmol). The mixture was stirred at room temperature for 15 min, during which a solution of ethyl 3-((3-ethoxy-3-oxopropyl)(methyl)amino)-3-oxopropanoate (1.17 g, 4.77 mmol) in ethanol (5 mL) was added. The resulting clear, colorless mixture was heated at 80° C. for 1 h, during which LC-MS indicated completion of reaction and a clean conversion to the desired ethyl 1-methyl-2,4-dioxopiperidine-3-carboxylate intermediate. Upon cooling to room temperature, the reaction was diluted with Et2O, resulting in the formation of a white precipitate (desired product). The white precipitate was collected via filtration, taken up in 5% aqueous HCl solution (8 mL), and refluxed for 1 h. The cooled mixture was extracted with CH2Cl2 (5×) and the combined organic extracts were dried (MgSO4), filtered, and concentrated in vacuo. Flash column chromatography (20% EtOAc/Hexanes to 100% EtOAc) afforded 1-methylpiperidine-2,4-dione as a viscous milky oil. [M+1]=128.1. was added completion of reaction Upon cooling to room temperature

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a 50-mL round bottomed flask was added ethanol (4 mL) under argon, followed by sodium (0.121 g, 5.25 mmol). The mixture was stirred at room temperature for 15 min, during which a solution of ethyl 3-((3-ethoxy-3-oxopropyl)(methyl)amino)-3-oxopropanoate (1.17 g, 4.77 mmol) in ethanol (5 mL) was added. The resulting clear, colorless mixture was heated at 80° C. for 1 h, during which LC-MS indicated completion of reaction and a clean conversion to the desired ethyl 1-methyl-2,4-dioxopiperidine-3-carboxylate intermediate. Upon cooling to room temperature, the reaction was diluted with Et2O, resulting in the formation of a white precipitate (desired product). The white precipitate was collected via filtration, taken up in 5% aqueous HCl solution (8 mL), and refluxed for 1 h. The cooled mixture was extracted with CH2Cl2 (5×) and the combined organic extracts were dried (MgSO4), filtered, and concentrated in vacuo. Flash column chromatography (20% EtOAc/Hexanes to 100% EtOAc) afforded 1-methylpiperidine-2,4-dione as a viscous milky oil. [M+1]=128.1. was added completion of reaction Upon cooling to room temperature

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indole-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Into a 50-mL round bottomed flask was added ethanol (4 mL) under argon, followed by sodium (0.121 g, 5.25 mmol). The mixture was stirred at room temperature for 15 min, during which a solution of ethyl 3-((3-ethoxy-3-oxopropyl)(methyl)amino)-3-oxopropanoate (1.17 g, 4.77 mmol) in ethanol (5 mL) was added. The resulting clear, colorless mixture was heated at 80° C. for 1 h, during which LC-MS indicated completion of reaction and a clean conversion to the desired ethyl 1-methyl-2,4-dioxopiperidine-3-carboxylate intermediate. Upon cooling to room temperature, the reaction was diluted with Et2O, resulting in the formation of a white precipitate (desired product). The white precipitate was collected via filtration, taken up in 5% aqueous HCl solution (8 mL), and refluxed for 1 h. The cooled mixture was extracted with CH2Cl2 (5×) and the combined organic extracts were dried (MgSO4), filtered, and concentrated in vacuo. Flash column chromatography (20% EtOAc/Hexanes to 100% EtOAc) afforded 1-methylpiperidine-2,4-dione as a viscous milky oil. [M+1]=128.1. was added completion of reaction Upon cooling to room temperature

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).

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

Procedure: Preparation of the title compound was carried out according to General Method 8. p-Tolylhydrazine hydrochloride (1.27 g, 8 mmol), 5-(2-bromoethyl)-2-methylpyridine (1.6 g, 8 mmol), triethyl amine (3.5 ml, 24 mmol) and 1-methylpiperidine-2,4-dione (4.2 g, 8 mmol) were taken in ethanol (25 ml) to obtain 40 mg of 1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one after purification on silica gel (230-400 mesh) chromatography eluting with methanol-dichloromethane gradient. To this intermediate (25 mg, 0.07 mmol) was added N-bromo succinamide (26 mg, 0.1), and azobisisobutyronitrile (1 mg) in carbon tetrachloride (10 ml) and the reaction mixture was heated at 80° C. for 12 h to obtain 5 mg of 4-bromo-1,2-dihydro-2,8-dimethyl-5-(2-(6-methylpyridin-3-yl)ethyl)-4H-pyrido[4,3-b]indol-3(5H)-one as a trifluoroacetate salt after purification by reverse-phase chromatography (C-18, 500 mm×50 mm, Mobile Phase A=0.05% TFA in water, B=0.05% TFA in acetonitrile, Gradient: 10% B to 80% B in 30 min, injection vol. 5 mL).