tert-butyl 3-aminopropanoate;hydrochloride

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

Procedure: To a stirred solution of methyl 3-(chlorosulfonyl)benzoate (5.0 g, 21.31 mmol) in pyridine (50 ml), was added dropwise a solution of tert-butyl 3-aminopropanoate hydrochloride (5.11 g, 23.44 mmol) in pyridine (10 ml) at 0° C. The resulting solution was allowed to warm to RT and stirred for 4 h. 1N HCl (50 ml) was added to the reaction mixture and the aqueous phase was separated and extracted with DCM (3×20 ml). The combined organic fractions were dried (MgSO4) and concentrated in vacuo to afford a viscous amber oil. Purification by chromatography on silica eluting with 0-100% EtOAc in iso-hexane afforded the title compound as a colourless oil. 1H NMR (400 MHz, CDCl3) δ 8.53 (1H, s), 8.27 (1H, d), 8.08 (1H, d), 7.63 (1H, t) 5.38 (1H, t), 3.97 (3H, s), 3.20 (2H, m), 2.48 (2H, t), 1.43 (9H, s). the aqueous phase was separated extracted with DCM (3×20 ml) The combined organic fractions were dried (MgSO4) concentrated in vacuo to afford a viscous amber oil Purification by chromatography on silica eluting with 0-100% EtOAc in iso-hexane

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

Procedure: DIEA (177 mg, 242 μl, 1.37 mmol, Eq: 5.00) was added to a mixture of (S)-5-((6-bromo-2-methoxynaphthalen-1-yl)methyl)-3-((S)-2-(tert-butoxycarbonyl(methyl)amino)propanamido)-4-oxo-2,3,4,5-tetrahydrobenzo[b][1,4]oxazepine-9-carboxylic acid (180 mg, 274 μmol, Eq: 1.00), tert-butyl 3-aminopropanoate hydrochloride (49.8 mg, 274 μmol, Eq: 1.00), HBTU (104 mg, 274 μmol, Eq: 1.0) and HOBT.H2O (37.0 mg, 274 μmol, Eq: 1.0) in DMF (3.41 mL) at 0° C. and the mixture was warmed to RT. After 45 min. the mixture was diluted with EtOAc, washed with H2O, brine, dried over Na2SO4, filtered and concentrated. The residue was purified by silica gel chromatography to afford 3-({(S)-9-(6-bromo-2-methoxy-naphthalen-1-ylmethyl)-7-[(S)-2-(tert-butoxycarbonyl-methyl-amino)-propionylamino]-8-oxo-6,7,8,9-tetrahydro-5-oxa-9-aza-benzocycloheptene-4-carbonyl}-amino)-propionic acid tert-butyl ester (150 mg, 69%) as an off-white foam. washed with H2O, brine dried over Na2SO4 filtered concentrated The residue was purified by silica gel chromatography

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

Procedure: A mixture of 5-methylsulfanyl-thiophene-2-carbaldehyde (1.0 g, 6.3 mmol) and 3-amino-propionic acid tert-butyl ester hydrochloride (1.02 g, 7 mmol) in DCM (20 mL) was stirred at RT for 15 min. Sodium triacetoxyborohydride (2 g, 9.45 mmol) was added and the reaction was stirred at room temperature overnight. The reaction mass was partitioned between aqueous sodium bicarbonate and DCM. The organic layer was dried over sodium sulfate and concentrated to give the crude 3-[(5-methylsulfanyl-thiophen-2-ylmethyl)-amino]-propionic acid tert-butyl ester (800 mg, 38% yield). This crude amine (800 mg, 2.4 mmol) was dissolved in DCM (10 mL) and Fmoc-isothiocyanate (740 mg, 2.6 mmol) was added. After stirring the reaction overnight at room temperature, piperidine (3 mL) was added and the deprotection reaction was stirred for 30 min. The reaction mixture was concentrated and purified using a silica gel column. Concentration of the appropriate fractions under vacuum gave the desired thiourea (600 mg, 63% yield). This material is unstable and should be kept in the cold to prevent decomposition by cyclization and loss of t-BuOH. LC-MS m/z: 347 (M+1)+. 1H NMR (400 MHz, CDCl3): δ 6.85 (d, 1H), 6.82 (d, 1H), 5.85 (s, 2H), 3.52 (t, 2H), 2.65 (t, 2H), 2.41 (s, 3H), 2.38 (s, 3H), 1.38 (s, 9H). the reaction was stirred at room temperature overnight The reaction mass was partitioned between aqueous sodium bicarbonate and DCM The organic layer was dried over sodium sulfate concentrated to give the crude 3-[(5-methylsulfanyl-thiophen-2-ylmethyl)-amino]-propionic acid tert-butyl ester (800 mg, 38% yield) After stirring the reaction overnight at room temperature the deprotection reaction was stirred for 30 min The reaction mixture was concentrated purified

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

Procedure: A mixture of 5-methylsulfanyl-thiophene-2-carbaldehyde (1.0 g, 6.3 mmol) and 3-amino-propionic acid tert-butyl ester hydrochloride (1.02 g, 7 mmol) in DCM (20 mL) was stirred at RT for 15 min. Sodium triacetoxyborohydride (2 g, 9.45 mmol) was added and the reaction was stirred at room temperature overnight. The reaction mass was partitioned between aqueous sodium bicarbonate and DCM. The organic layer was dried over sodium sulfate and concentrated to give the crude 3-[(5-methylsulfanyl-thiophen-2-ylmethyl)-amino]-propionic acid tert-butyl ester (800 mg, 38% yield). This crude amine (800 mg, 2.4 mmol) was dissolved in DCM (10 mL) and Fmoc-isothiocyanate (740 mg, 2.6 mmol) was added. After stirring the reaction overnight at room temperature, piperidine (3 mL) was added and the deprotection reaction was stirred for 30 min. The reaction mixture was concentrated and purified using a silica gel column. Concentration of the appropriate fractions under vacuum gave the desired thiourea (600 mg, 63% yield). This material is unstable and should be kept in the cold to prevent decomposition by cyclization and loss of t-BuOH. LC-MS m/z: 347 (M+1)+. 1H NMR (400 MHz, CDCl3): δ 6.85 (d, 1H), 6.82 (d, 1H), 5.85 (s, 2H), 3.52 (t, 2H), 2.65 (t, 2H), 2.41 (s, 3H), 2.38 (s, 3H), 1.38 (s, 9H). the reaction was stirred at room temperature overnight The reaction mass was partitioned between aqueous sodium bicarbonate and DCM The organic layer was dried over sodium sulfate concentrated to give the crude 3-[(5-methylsulfanyl-thiophen-2-ylmethyl)-amino]-propionic acid tert-butyl ester (800 mg, 38% yield) After stirring the reaction overnight at room temperature the deprotection reaction was stirred for 30 min The reaction mixture was concentrated purified

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

Procedure: A mixture of 5-ethyl-thiophene-2-carboxaldehyde (14.25 g, 101.6 mmol) and 3-amino-propionic acid tert-butyl ester hydrochloride (22.2 g, 122 mmol) in DCM was stirred for 3 hr at RT. Sodium triacetoxyborohydride (30.1 g, 142.2 mmol) was added in portions and the reaction was stirred for 2 h, at which point TLC indicated the completion of the reaction. To the reaction mixture was added a saturated aq solution of sodium bicarbonate, and then the phases were separated. The aqueous layer was extracted with DCM two times. The combined organic extracts were dried over sodium sulfate, concentrated under vacuum and the resulting material was purified on a silica gel column (eluent: hexanes→2% hexanes in EtOAc→5% hexanes in EtOAc→10% hexanes in EtOAc→20% hexanes in EtOAc→50% hexanes in EtOAc) to give 3-[(5-ethyl-thiophen-2-ylmethyl)-amino]-propionic acid tert-butyl ester (8.91 g, 32.6% yield). the reaction was stirred for 2 h, at which point TLC the completion of the reaction the phases were separated The aqueous layer was extracted with DCM two times The combined organic extracts were dried over sodium sulfate concentrated under vacuum the resulting material was purified on a silica gel column (eluent: hexanes→2% hexanes in EtOAc→5% hexanes in EtOAc→10% hexanes in EtOAc→20% hexanes in EtOAc→50% hexanes in EtOAc)

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

Procedure: A mixture of 5-ethyl-thiophene-2-carboxaldehyde (14.25 g, 101.6 mmol) and 3-amino-propionic acid tert-butyl ester hydrochloride (22.2 g, 122 mmol) in DCM was stirred for 3 hr at RT. Sodium triacetoxyborohydride (30.1 g, 142.2 mmol) was added in portions and the reaction was stirred for 2 h, at which point TLC indicated the completion of the reaction. To the reaction mixture was added a saturated aq solution of sodium bicarbonate, and then the phases were separated. The aqueous layer was extracted with DCM two times. The combined organic extracts were dried over sodium sulfate, concentrated under vacuum and the resulting material was purified on a silica gel column (eluent: hexanes→2% hexanes in EtOAc→5% hexanes in EtOAc→10% hexanes in EtOAc→20% hexanes in EtOAc→50% hexanes in EtOAc) to give 3-[(5-ethyl-thiophen-2-ylmethyl)-amino]-propionic acid tert-butyl ester (8.91 g, 32.6% yield). the reaction was stirred for 2 h, at which point TLC the completion of the reaction the phases were separated The aqueous layer was extracted with DCM two times The combined organic extracts were dried over sodium sulfate concentrated under vacuum the resulting material was purified on a silica gel column (eluent: hexanes→2% hexanes in EtOAc→5% hexanes in EtOAc→10% hexanes in EtOAc→20% hexanes in EtOAc→50% hexanes in EtOAc)

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

Procedure: Tert-butyl isocyanopropionate was synthesised in two steps from commercially available β-alanine tert-butyl ester hydrochloride (NovaBiochem) as follows. To a solution of β-alanine tert-butyl ester hydrochloride (2 g, 11 mmol) in tetrahydrofuran (5 mL) and ethyl formate (5 mL) was added triethylamine (12 mmol, 1.7 mL). The flask was fitted with a reflux condenser and the mixture was heated for 4 hours, after which another quantity of ethyl formate was added (1 mL). An hour later, the mixture was filtered over silica gel. The silica gel was washed with ethyl acetate. The volatiles were removed from the filtrate, yielding N-formyl β-alanine tert-butyl ester (1.4 g, 11 mmol). 13C-NMR (50 MHz, CDCl3) δ 171.2, 163.4, 80.8, 34.7, 33.4, 22.7; 1H-NMR (200 MHz, CDCl3, TMS) δ 8.15 (s, 1H), 6.31 (broad s, 1H), 3.52 (q, 2H, J=6.1 Hz), 2.47 (t, 2H, J=6.2 Hz), 1.46 (s, 9H). This compound (0.65 g, 3.8 mmol) was subjected to the dehydration conditions described for the above nitrile to afford tert-butyl isocyanopropionate (0.50 g, 3.2 mmol, 85%) as a yellowish liquid. The colour darkened during storage at 4° C. (up to two months), but this did not greatly affect the quality of the product. 1H-NMR (200 MHz, CDCl3, TMS) δ 3.64 (m, 2H), 1.48 (s, 9H). The flask was fitted with a reflux condenser the mixture was heated for 4 hours An hour later, the mixture was filtered over silica gel The silica gel was washed with ethyl acetate The volatiles were removed from the filtrate

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

Procedure: 3.24 g (20 mmol) of 4-tert-butyl benzaldehyde, 3.63 g (20 mmol) of beta-alanine tert-butylester hydrochloride and 2.22 g (22 mmol) of triethyl amine were dissolved in 20 ml methanol and stirred at rt for 1 h. 1.11 g (30 mmol) of sodium borohydride were added in portions under nitrogen and the reaction mixture was stirred for 2 h at rt after complete addition. Water was added and the solvent was evaporated. The residue was extracted twice with diethyl ether. The combined organic layers were washed twice with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and the solvent was evaporated. The residue was purified by column chromatography (silica gel, diethyl ether) to yield 4.62 g (79%) product as a colorless oil. 1H NMR (DMSO-d6, 300 MHz): δ 7.34 (d, 2H), 7.25 (d, 2H), 3.76 (s, 2H), 2.86 (t, 2H), 2.45 (t, 2H), 1.44 (s, 9H), 1.31 (s, 9H). the reaction mixture was stirred for 2 h at rt after complete addition the solvent was evaporated The residue was extracted twice with diethyl ether The combined organic layers were washed twice with saturated aqueous sodium chloride solution dried over sodium sulfate filtered the solvent was evaporated The residue was purified by column chromatography (silica gel, diethyl ether)

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

Procedure: 3.24 g (20 mmol) of 4-tert-butyl benzaldehyde, 3.63 g (20 mmol) of beta-alanine tert-butylester hydrochloride and 2.22 g (22 mmol) of triethyl amine were dissolved in 20 ml methanol and stirred at rt for 1 h. 1.11 g (30 mmol) of sodium borohydride were added in portions under nitrogen and the reaction mixture was stirred for 2 h at rt after complete addition. Water was added and the solvent was evaporated. The residue was extracted twice with diethyl ether. The combined organic layers were washed twice with saturated aqueous sodium chloride solution, dried over sodium sulfate, filtered and the solvent was evaporated. The residue was purified by column chromatography (silica gel, diethyl ether) to yield 4.62 g (79%) product as a colorless oil. 1H NMR (DMSO-d6, 300 MHz): δ 7.34 (d, 2H), 7.25 (d, 2H), 3.76 (s, 2H), 2.86 (t, 2H), 2.45 (t, 2H), 1.44 (s, 9H), 1.31 (s, 9H). the reaction mixture was stirred for 2 h at rt after complete addition the solvent was evaporated The residue was extracted twice with diethyl ether The combined organic layers were washed twice with saturated aqueous sodium chloride solution dried over sodium sulfate filtered the solvent was evaporated The residue was purified by column chromatography (silica gel, diethyl ether)

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (3,5-Bis-trifluoromethyl-benzyl)-[2-(butyl-ethyl-amino)-5-trifluoromethyl-benzyl]-(6-chloropyrimidin-4-yl)-amine (300 mg) is dissolved in toluene (5 ml), and thereto are added 3-aminopropionic acid tert-butyl ester hydrochloride (888 mg) and N-ethyldiisopropylamine (1.7 ml), and the mixture is stirred at 120° C. overnight. To the reaction solution are added ethyl acetate and a 1N-hydrochloric acid, and the mixture is separated. The organic layer is washed with a saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The resulting residue is purified by column chromatography (hexane:ethyl acetate=9:1→3:1) to give tert-butyl 3-(6-{(3,5-bis-trifluoromethyl-benzyl)-[2-(butyl-ethyl-amino)-5-trifluoromethyl-benzyl]-amino}-pyrimidin-4-ylamino)-propionate (70 mg). MS (m/z): 722 [M+H]+ a 1N-hydrochloric acid, and the mixture is separated The organic layer is washed with a saturated brine dried over magnesium sulfate concentrated under reduced pressure The resulting residue is purified by column chromatography (hexane:ethyl acetate=9:1→3:1)

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (3,5-Bis-trifluoromethyl-benzyl)-[2-(butyl-ethyl-amino)-5-trifluoromethyl-benzyl]-(6-chloropyrimidin-4-yl)-amine (300 mg) is dissolved in toluene (5 ml), and thereto are added 3-aminopropionic acid tert-butyl ester hydrochloride (888 mg) and N-ethyldiisopropylamine (1.7 ml), and the mixture is stirred at 120° C. overnight. To the reaction solution are added ethyl acetate and a 1N-hydrochloric acid, and the mixture is separated. The organic layer is washed with a saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The resulting residue is purified by column chromatography (hexane:ethyl acetate=9:1→3:1) to give tert-butyl 3-(6-{(3,5-bis-trifluoromethyl-benzyl)-[2-(butyl-ethyl-amino)-5-trifluoromethyl-benzyl]-amino}-pyrimidin-4-ylamino)-propionate (70 mg). MS (m/z): 722 [M+H]+ a 1N-hydrochloric acid, and the mixture is separated The organic layer is washed with a saturated brine dried over magnesium sulfate concentrated under reduced pressure The resulting residue is purified by column chromatography (hexane:ethyl acetate=9:1→3:1)

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

Procedure: Tert-butyl 3-aminopropanoate hydrochloride (5 g, 27.7 mmol) was dissolved in methanol (150 mL). Diisopropylethylamin (4.73 mL, 27.7 mmol) was added followed by 4-carboxybenzaldehyde. The mixture is heated to reflux for 1 hour. After cooling to room temperature sodium cyanoborohydride (1.77 g, 22.1 mmol) was added under nitrogen and stirred for 1 hour at room temperature. Acetic acid (15 mL) was added and the mixture was stirred for an additional 1 hour. The mixture was poured into water (300 mL) and stirred at room temperature over night. The water solution was washed with ethyl acetate (3×250 mL). The organic phase dried (Na2SO4) and solvent removed in vacuo to yield the crude product as an oil which solidifies by standing. The crude product was used in the next step without further purification. The mixture is heated to reflux for 1 hour was added under nitrogen the mixture was stirred for an additional 1 hour stirred at room temperature over night The water solution was washed with ethyl acetate (3×250 mL) The organic phase dried (Na2SO4) and solvent removed in vacuo