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                            The BI-3802 was designed by Boehringer Ingelheim and could be obtained free of charge through the Boehringer Ingelheim open innovation portal opnMe.com, associated with its negative control.
 
                
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| CAS No. : | 42303-42-4 | 
| Formula : | C6H12ClNO2 | 
| M.W : | 165.62 | 
| SMILES Code : | Cl.C(C)OC(=O)C1(CC1)N | 
| MDL No. : | MFCD00190747 | 
| InChI Key : | XFNUTZWASODOQK-UHFFFAOYSA-N | 
| Pubchem ID : | 386203 | 
| GHS Pictogram: |   | 
| Signal Word: | Warning | 
| Hazard Statements: | H302-H315 | 
| Precautionary Statements: | P280 | 
| Num. heavy atoms | 10 | 
| Num. arom. heavy atoms | 0 | 
| Fraction Csp3 | 0.83 | 
| Num. rotatable bonds | 3 | 
| Num. H-bond acceptors | 3.0 | 
| Num. H-bond donors | 1.0 | 
| Molar Refractivity | 39.84 | 
| TPSA ? Topological Polar Surface Area: Calculated from  | 52.32 Ų | 
| Log Po/w (iLOGP)? iLOGP: in-house physics-based method implemented from  | 0.0 | 
| Log Po/w (XLOGP3)? XLOGP3: Atomistic and knowledge-based method calculated by  | 0.72 | 
| Log Po/w (WLOGP)? WLOGP: Atomistic method implemented from  | 0.78 | 
| Log Po/w (MLOGP)? MLOGP: Topological method implemented from  | 0.35 | 
| Log Po/w (SILICOS-IT)? SILICOS-IT: Hybrid fragmental/topological method calculated by  | 0.51 | 
| Consensus Log Po/w? Consensus Log Po/w: Average of all five predictions | 0.47 | 
| Log S (ESOL):? ESOL: Topological method implemented from  | -1.12 | 
| Solubility | 12.5 mg/ml ; 0.0754 mol/l | 
| Class? Solubility class: Log S scale  | Very soluble | 
| Log S (Ali)? Ali: Topological method implemented from  | -1.4 | 
| Solubility | 6.64 mg/ml ; 0.0401 mol/l | 
| Class? Solubility class: Log S scale  | Very soluble | 
| Log S (SILICOS-IT)? SILICOS-IT: Fragmental method calculated by  | -0.78 | 
| Solubility | 27.3 mg/ml ; 0.165 mol/l | 
| Class? Solubility class: Log S scale  | Soluble | 
| GI absorption? Gatrointestinal absorption: according to the white of the BOILED-Egg | High | 
| BBB permeant? BBB permeation: according to the yolk of the BOILED-Egg | Yes | 
| P-gp substrate? P-glycoprotein substrate: SVM model built on 1033 molecules (training set)  | No | 
| CYP1A2 inhibitor? Cytochrome P450 1A2 inhibitor: SVM model built on 9145 molecules (training set) | No | 
| CYP2C19 inhibitor? Cytochrome P450 2C19 inhibitor: SVM model built on 9272 molecules (training set) | No | 
| CYP2C9 inhibitor? Cytochrome P450 2C9 inhibitor: SVM model built on 5940 molecules (training set) | No | 
| CYP2D6 inhibitor? Cytochrome P450 2D6 inhibitor: SVM model built on 3664 molecules (training set) | No | 
| CYP3A4 inhibitor? Cytochrome P450 3A4 inhibitor: SVM model built on 7518 molecules (training set) | No | 
| Log Kp (skin permeation)? Skin permeation: QSPR model implemented from  | -6.8 cm/s | 
| Lipinski? Lipinski (Pfizer) filter: implemented from  | 0.0 | 
| Ghose? Ghose filter: implemented from  | None | 
| Veber? Veber (GSK) filter: implemented from  | 0.0 | 
| Egan? Egan (Pharmacia) filter: implemented from  | 0.0 | 
| Muegge? Muegge (Bayer) filter: implemented from  | 1.0 | 
| Bioavailability Score? Abbott Bioavailability Score: Probability of F > 10% in rat  | 0.55 | 
| PAINS? Pan Assay Interference Structures: implemented from  | 0.0 alert | 
| Brenk? Structural Alert: implemented from  | 0.0 alert: heavy_metal | 
| Leadlikeness? Leadlikeness: implemented from  | No; 1 violation:MW<1.0 | 
| Synthetic accessibility? Synthetic accessibility score:  from 1 (very easy) to 10 (very difficult) | 1.38 | 
* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.

| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 100% | With thionyl chloride; at 0℃; for 2h;Reflux; Green chemistry; | The compound of the formula II (500.0 g, 4.95 mol) was added to ethanol (10 L) at room temperature, and thionyl chloride(883.4g, 7.43 mol) was added dropwise at 0 C, and the reaction mixture was heated to reflux and stirred for 2 h. The solution was cooled to room temperature, concentrated, and washed three times with THF (1L×3) to give the compound of formula III, 819.8 g, yield 100%. | 
| 80.6% | With thionyl chloride; at 0 - 70℃; for 20h; | Thionyl chloride (150 mL, 2.056 mol) was added slowly below 0 C to a suspension of 1- aminocyclopropanecarboxylic acid (100 g, 0.989 mol) in anhydrous ethanol (1 L). The mixture was stirred at 70 C for 20 h. TLC (methanol, f = 0.4) showed that most of the starting material was consumed. Then the solution was concentrated to give 210 g of crude product. The residue was dissolved in water and adjusted to a pH between 9 and 10 with potassium carbonate. The aqueous layer was extracted with dichloromethane (1 L x 3). The combined organic layers were concentrated to dryness. The residue was dissolved in ethyl acetate (300 mL) and hydrochloride in ethyl acetate (250 mL, 4M) was added slowly to the solution below -30 C. It was stirred for 30 min at 0 C. A solid precipitated and it was filtered under nitrogen atmosphere to give ethyl 1- aminocyclopropanecarboxylate hydrochloride (132 g, 80.6% yield) as a white solid. The following 1H-NMR is from the free amine. 1H-NMR (400MHz, chloroform-di): delta [ppm] = 0.91-1.02 (m, 2H), 1.15-1.30 (m, 5H), 2.17 (s, 2H), 4.10 (d, 2H). | 
| 80.6% | Thionyl chloride (150 mL, 2.056 mol) was added slowly below 0 C to a suspension of 1- aminocyclopropanecarboxylic acid (100 g, 0.989 mol) in anhydrous ethanol (1 L). The mixture was stirred at 70 C for 20 h. TLC (methanol, Rf = 0.4) showed that most of the starting material wasconsumed. Then the solution was concentrated to give 210 g of crude product. The residue was dissolved in water and adjusted to a pH between 9 and 10 with potassium carbonate. The aqueous layer was extracted with dichloromethane (1 L x 3). The combined organic layers were concentrated to dryness. The residue was dissolved in ethyl acetate (300 mL) and hydrochloride in ethyl acetate (250 mL, 4M) was added slowly to the solution below -30C. It was stirred for 30 mm at 0C. A solid precipitated and it was filtered under nitrogen atmosphere to give ethyl 1-aminocyclopropanecarboxylate hydrochloride (132 g, 80.6% yield) as a white solid.The following ?H-N MR is from the free amine.?H-NMR (400MHz, chloroform-d,): 6 [ppm] = 0.91-1.02 (m, 2H), 1.15-1.30 (m, 5H), 2.17 (s, 2H), 4.10 (d, 2H). | 
| With thionyl chloride; for 8h;Heating / reflux; | a) A suspension of 6.15 g of 1-aminocyclopropanecarboxylic acid in 100 ml of ethanol is prepared and 6.5 ml of thionyl chloride are added gradually. The reaction mixture is refluxed gently for 8 hours and then concentrated under reduced pressure, toluene being added to drive off the ethanol. This gives 10 g of the hydrochloride of the ethyl ester of the starting acid. | 

| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With sodium hydrogencarbonate; In N,N-dimethyl-formamide; at 20℃; for 18h; | A mixture of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (1.0 g, 7.74 mmol), 2-bromoacetophenone (3.08 g, 15.5 mmol), and NaHCO3 (1.30 g, 15.5 mmol) in DMF (20 mL) was stirred at ambient temperature for 18 h. H2O (20 mL) was added and the mixture was extracted with EtOAc (2×75 mL). The combined organic layers were dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by HPLC using a reversed phase C18 column and eluting with a gradient of H2O:CH3CN:CF3CO2H-90:10:0.1 to 5:95:0.1. The product-containing fractions were combined, adjusted to pH 10 by addition of saturated aqueous Na2CO3 and extracted with EtOAc (2×75 nL). The combined organic layers were dried over Na2SO4, filtered, and concentrated in vacuo to provide the title compound. MS: m/z=248 (M+1). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With hydrogenchloride; In ethyl acetate; at 20℃; for 1h; | Step 3: 1-Ethoxycarbonyl-cyclopropyl-ammonium chloride A saturated solution of HCl in ethyl acetate (20 mL) was added under nitrogen to a solution of 1-[[(1,1-dimethylethoxy)carbonyl]amino]cyclopropane carboxylic acid ethyl ester (10.07 g, 43.9 mmol), prepared in the previous step, in 20 mL of ethyl acetate at room temperature. After the addition, the reaction was stirred at room temperature for 1 h. The solid present was collected by filtration, rinsed with ethyl acetate and dried under reduced pressure to give 1-ethoxycarbonyl-cyclopropyl-ammonium chloride as a white solid. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 36% | With triethylamine; In ethanol; at 65℃; for 96h; | Step 4: Ethyl 1-[4-(4-bromophenyl)-1,3-thiazol-2-yl]amino}cyclopropane carboxylate Triethylamine (3.1 mL, 22.3 mmol) was added under nitrogen to a mixture of 2-(4-bromophenyl)-2-oxoethyl thiocyanate (5.2024 g, 20.3 mmol), prepared in step 1 of Example 1, and 1-ethoxycarbonyl-cyclopropyl-ammonium chloride (3.7001 g, 22.3 mmol), prepared in the previous step, in 400 mL of absolute ethanol. After the addition, the reaction was stirred at 65 C. for 4 days. The reaction was concentrated under reduced pressure to remove the ethanol. The residue was taken up in methylene chloride, applied to a Biotage FLASH 25+ cartridge and the methylene chloride allowed to evaporate. Purification of the residue on the samplet on a Horizon Flash Collector (the Biotage FLASH 25+ cartridge) using a linear gradient of 5% ethyl acetate-hexane to 100% ethyl acetate gave ethyl 1-[4-(4-bromophenyl)-1,3-thiazol-2-yl]amino}cyclopropane carboxylate (2.66 g, 36%) as a light yellow solid, mp 152-154 C.; MS m/z 367. | 
 [ 7732-18-5 ]
                                                    
                                                    [ 7732-18-5 ]
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
 [ 194086-61-8 ]
                                                    
                                                    [ 194086-61-8 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 354 mg (28%) | With triethylamine; In sodium hydroxide; ethanol; | Example 8 1-(6-Chloro-1,1-dioxo-1,4-dihydro-thieno[3,2-e]-1lambda6,2,4-thiadiazin-3-ylamino)-cyclopropanecarboxylic acid A mixture of 3,6-dichloro-4H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (1.0 g, 3.9 mmol), <strong>[42303-42-4]1-aminocyclopropanecarboxylic acid ethyl ester hydrochloride</strong> (1.29 g, 7.8 mmol) and triethylamine (1.1 ml, 7.8 mmol) in ethanol (6 ml) was stirred for 23 h at 120C in a sealed flask.. The cooled solution was concentrated in vacuo and the residue was triturated with water followed by adjustment to PH <2 with 4M hydrochloric acid.. The resulting crude dark material was isolated by filtration and boiled in 1 N sodium hydroxide followed by treatment with decolourising charcoal.. After filtration, the solution was acidified to PH <2 with 4M hydrochloric acid and the precipitate was filtered off and recrystallized from ethanol to give 354 mg (28 %) of the title compound; mp 299-300C (dec.); 1H-NMR (DMSO-d6): delta 1.17 (br s, 2H), 1.49 (br s, 2H), 7.09 (s, 1H), 8.1 (br s, 1H), 11.15 (br s, 1H), 12.7 (br s, 1H); MS: m/e 303/305 (M-H2O)+. | 
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
 [ 194086-61-8 ]
                                                    
                                                    [ 194086-61-8 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 151 mg (11%) | With triethylamine; In ethanol; | Example 7 1-(6-Chloro-1,4-dihydro-1,1-dioxo-thieno[3,2-e]-1lambda6,2,4-thiadiazin-3-ylamino)-cyclopropanecarboxylic acid ethyl ester A mixture of 3,6-dichloro-4H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (1.0 g, 3.9 mmol), <strong>[42303-42-4]1-aminocyclopropanecarboxylic acid ethyl ester hydrochloride</strong> (1.29 g, 7.8 mmol) and triethylamine (1.1 ml, 7.8 mmol) in ethanol (6 ml) was stirred for 23 h at 120C in a sealed flask.. The cooled solution was concentrated in vacuo and the residue was triturated with water followed by adjustment to PH <2 with 4M hydrochloric acid.. The resulting crude dark material was isolated by filtration and purified by chromatography (ethyl acetate) to give 151 mg (11 %) of the title compound; mp 190-194C (dec.); 1H-NMR (DMSO-d6): delta 1.15 (t, 3H), 1.22 (m, 2H), 1.50 (m, 2H), 4.09 (q, 2H), 7.06 (s, 1H), 8.14 (br s, 1H), 11.14 (br s, 1H); MS: m/e 349/351 (M+). | 
| 151 mg (11%) | With triethylamine; In ethanol; | EXAMPLE 7 1-(6-Chloro-1,4-dihydro-1,1-dioxo-thieno[3,2-e]-1lambda6,2,4-thiadiazin-3-ylamino)-cyclopropanecarboxylic acid ethyl ester A mixture of 3,6-dichloro-4H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (1.0 g, 3.9 mmol), <strong>[42303-42-4]1-aminocyclopropanecarboxylic acid ethyl ester hydrochloride</strong> (1.29 g, 7.8 mmol) and triethylamine (1.1 ml, 7.8 mmol) in ethanol (6 ml) was stirred for 23 h at 120C in a sealed flask. The cooled solution was concentrated in vacuo and the residue was triturated with water followed by adjustment to pH <2 with 4M hydrochloric acid. The resulting crude dark material was isolated by filtration and purified by chromatography (ethyl acetate) to give 151 mg (11 %) of the title compound; mp 190-194C (dec.); 1H-NMR (DMSO-d6): delta 1.15 (t, 3H), 1.22 (m, 2H), 1.50 (m, 2H), 4.09 (q, 2H), 7.06 (s, 1H), 8.14 (br s, 1H), 11.14 (br s, 1H); MS: m/e 349/351 (M+). | 
| 151 mg (11%) | With triethylamine; In ethanol; | Example 7 1-(6-Chloro-1,4-dihydro-1,1-dioxo-thieno[3,2-e]-1lambda6,2,4-thiadiazin-3-ylamino)-cyclopropanecarboxylic acid ethyl ester A mixture of 3,6-dichloro-4H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (1.0 g, 3.9 mmol), <strong>[42303-42-4]1-aminocyclopropanecarboxylic acid ethyl ester hydrochloride</strong> (1.29 g, 7.8 mmol) and triethylamine (1.1 ml, 7.8 mmol) in ethanol (6 ml) was stirred for 23 h at 120 C. in a sealed flask. The cooled solution was concentrated in vacuo and the residue was triturated with water followed by adjustment to pH <2 with 4M hydrochloric acid. The resulting crude dark material was isolated by filtration and purified by chromatography (ethyl acetate) to give 151 mg (11%) of the title compound; mp 190-194 C. (dec.); 1H-NMR (DMSO-d6): delta1.15 (t, 3H), 1.22 (m, 2H), 1.50 (m, 2H), 4.09 (q, 2H), 7.06 (s, 1H), 8.14 (br s, 1H), 11.14 (br s, 1H); MS: m/e 349/351 (M+). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With sodium acetate; sodium tris(acetoxy)borohydride; In dichloromethane; | 25.0 g (0.19 mol) of ethyl l-aminocyclopropane-l-carboxylate x HCl and 16.8 g (0.20 mol) of cyclopentanone are dissolved in 300 mL of dichloromethane and combined with 16.4 g (0.20 mol) of sodium acetate and 61.7 g (0.29 mol) of sodium triacetoxyborohydride. It is stirred overnight and the reaction mixture is then poured onto 400 mL of 10% sodium hydrogen carbonate solution. The aqueous phase is extracted with dichloromethane. The combined organic phases are dried over Na2SO4 and evaporated down. Yield: 34.5 g of a compound Z4a (colourless oil) | |
| With sodium acetate; sodium tris(acetoxy)borohydride; In dichloromethane; | 25.0 g (0.19 mol) ethyl 1-aminocyclopropane-1-carboxylate×HCl and 16.8 g (0.20 mol) cyclopentanone are dissolved in 300 mL dichloromethane and combined with 16.4 g (0.20 mol) sodium acetate and 61.7 g (0.29 mol) sodium triacetoxyborohydride. The mixture is stirred overnight and the reaction mixture is then poured onto 400 mL 10% sodium hydrogen carbonate solution. The aqueous phase is extracted with dichloromethane. The combined organic phases are dried over Na2SO4 and evaporated down. Yield: 34.5 g of a compound Z4a (colourless oil) | |
| With sodium acetate; sodium tris(acetoxy)borohydride; In dichloromethane; | 25.0 g (0.19 mol) of ethyl 1-aminocyclopropane-1-carboxylate×HCl and 16.8 g (0.20 mol) of cyclopentanone were dissolved in 300 mL of dichloromethane and combined with 16.4 g (0.20 mol) of sodium acetate and 61.7 g (0.29 mol) of sodium triacetoxyborohydride. It was stirred overnight and the reaction mixture was then poured onto 400 mL of 10% sodium hydrogen carbonate solution. The aqueous phase was extracted with dichloromethane. The combined organic phases were dried over Na2SO4 and evaporated down. Yield: 34.5 g of a compound Z4a (colourless oil) | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 95% | 1a) ethyl 1-[(pyrimidine-5-carbonyl)-amino]-cyclopropanecarboxylate A solution of 15.74 g (126.9 mmol) pyrimidine-5-carboxylic acid, 43.57 mL (312.6 mmol) triethylamine and 44.61 g (138.9 mmol) TBTU in 460 mL THF was stirred for 30 minutes at ambient temperature. Then 9.11 g (127.3 mmol) ethyl 1-amino-cyclopropane-carboxylate hydrochloride were added and the mixture was stirred further overnight. Then the mixture was evaporated down and the residue was combined with 200 mL water, made alkaline with dilute potassium carbonate solution and extracted with ethyl acetate. The intermediate product was purified by column chromatography (silica gel, dichloromethane+0-4% methanol). Yield: 95% of theory C11H13N3O3 (235.24) Rt=1.23 min. method 1 | |
| 88% | 1a) ethyl 1-[(pyrimidine-5-carbonyl)-amino]-cyclopropanecarboxylateA solution of 6.80 g (54.8 mmol) of pyrimidine-5-carboxylic acid, 18.82 mL (135 mmol) of triethylamine and 19.27 g (60 mmol) of TBTU in 200 mL THF was stirred for 30 minutes at ambient temperature. Then 9.11 g (55 mmol) of ethyl 1-amino-cyclopropanecarboxylate hydrochloride were added and the mixture was stirred further overnight. Then the mixture was evaporated down, the residue was stirred with 200 mL water and the crude product was extracted with ethyl acetate. The intermediate product was purified by column chromatography (silica gel, dichloromethane+0-4% methanol).Yield: 88% of theoryC11H13N3O3 (235.24)Mass spectrum: [M+H]+=236 | |
| With 1-hydroxy-7-aza-benzotriazole; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine; In dichloromethane; for 16h; | Reference Example 3: Preparation of L-[(PYRIMIDIN-5-YLCARBONYL) amino] cyclopropanecarboxylic acid compound with chlorolithium (1: 1). Triethylamine (7.026g, 69.44 mmol) was added to a suspension of 1- (ethoxycarbonyl) cyclopropanaminium chloride (11. 50g, 69. 44 mmol), PYRIMIDINE-5-CARBOXYLIC acid (8.617g, 69.44 mmol), EDC (13.312g, 69.44 mmol), and HOAT (0.945g, 69.44 mmol) in CH2C12 (125mL) and allowed to stir for 16 hours. The reaction was adsorbed onto silica and purified by silica gel chromatography and eluted with ethyl acetate to yield ethyl 1- [ (PYRIMIDIN-5-YLCARBONYL) AMINO]- cyclopropanecarboxylate as a white solid. Low resolution mass spectrometry: (M+H+) = 236.2. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 24% | With triethylamine;copper; In dichloromethane; at 20℃; | b) 1.25 g of the ester hydrochloride obtained above are mixed with 6.25 g of diacetyltri(4-phenoxyphenyl)bismuth in 20 ml of dichloromethane, and 1.1 ml of triethylamine and 22 mg of copper powder are added. The reaction mixture is stirred at room temperature overnight and then chromatographed on silica gel using a dichloromethane/cyclohexane mixture (8/2; v/v) as the eluent to give 0.47 g of the expected product (yield=24%). M.p.=80 C. | 

 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
 [ 902169-69-1 ]
                                                    
                                                    [ 902169-69-1 ]| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate; triethylamine; In acetonitrile; at 20℃; for 24h; | Et3N (54 mg, 0.532 mmol) was added to a mixture of 2-carboxymethyl-l-(4-iso- propoxyphenyl)-5-(4-trifluoromethylphenoxy)indole-3-carboxylic acid ethyl ester (144 mg, 0.266 mmol, see step (d) above), 1 -amino- 1 -eye lopropanecarboxy lie acid ethyl ester hydrochloride (44 mg, 0.266 mmol), HBTU (101 mg, 0.266 mmol) and anhydrous MeCN (10 mL). The mixture was stirred at rt for 24 h. NaHCO3 (aq, sat, 10 mL) was added and the mixture was extracted with EtOAc. The organic layer was washed with saturated NaHCO3 (aq, sat, 10 mL) and brine (15 mL), dried (Na2SO4) and concentrated to give the sub-title compound which was used in the next step without further purification. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 98% | Example 67; 5-Cvano-1-(3-trifluoromethoxybenzyl)-1H-indole-2-carboxylic acid (1- hvdroxymethylcvclopropyDamide1-Amino-cyclopropanecarboxylic acid ethyl ester hydrochloride (350mg, 2.11mmol) was dissolved in anhydrous THF (15ml) and cooled to 00C under argon. A 1.0M solution of lithium aluminium hydride in THF (2.5ml, 2.50mmol) was added dropwise and the reaction allowed to warm to room temperature and stirred for 17 h. The reaction was quenched by EPO <DP n="51"/>cautious addition of sodium sulfate decahydrate until evolution of hydrogen had ceased. The suspension was stirred for 2 h, filtered through Dicalite and the residue washed thoroughly with ether. The filtrate and washings were combined and concentrated to yield (i-amino-cyclopropyl)methanol (180mg, 98%) as a colourless oil. | |
| 95% | With lithium aluminium tetrahydride; In tetrahydrofuran; at 0℃; for 2h;Inert atmosphere; | To a stirred solution of lithium aluminum hydride (1.3 g, 36.23 mmol) in THF (30 mL) under an argon atmosphere was added <strong>[42303-42-4]ethyl 1-aminocyclopropane-1-carboxylate hydrochloride</strong> (3 g, 18.11 mmol) at 0 oC and stirred for 2 h. After consumption of starting material (monitored by TLC), the reaction mixture was quenched with a saturated sodium sulfate solution (100 mL) and stirred for 1 h. The reaction mixture was filtered and washed with 20% MeOH: CH2Cl2. The filtrate was concentrated in vacuo to obtain (1- aminocyclopropyl) methanol (1.5 g, 95%) as a colorless liquid used in the next step without further purification. TLC: EtOAc (Rf: 0.1). | 

 [ 652-39-1 ]
                                                    
                                                    [ 652-39-1 ]
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With triethylamine; In tetrahydrofuran; chloroform; | PREPARATION 6 2-(1'-Ethoxycarbonylcyclopropyl)-1,3-dioxo-4-fluoroisoindoline 3-Fluorophthalic anhydride (2.0 g), ethyl 1-aminocyclopropane carboxylate hydrochloride (4.0 g) and triethylamine (4 ml) were stirred in chloroform (30 ml) for 0.5 h. Volatile material was evaporated and the residue was heated at 210 for 0.25 h in a nitrogen atmosphere; the residue was dissolved in THF (insoluble triethylame hydrochloride was discarded) and the ethereal solution was evaporated to dryness. This residue was recrystallized from dichloromethane/light petroleum (40-60) to give the title compound m.p. 164. | 
 [ 59882-98-3 ]
                                                    
                                                    [ 59882-98-3 ]
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With potassium carbonate; In tetrahydrofuran; chloroform; water; | EXAMPLE 49 2-(1'-Hydroxymethylcyclopropyl)benz[e]isoindoline hydrochloride Ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong> (16 g) in chloroform (50 ml) was added to 1,2-bis(bromomethyl)naphthalene (40 g) and potassium carbonate (40 g) in chloroform (200 ml) kept at 60. The reaction mixture was refluxed for a further 6 hr and then filtered; the filtrate was evaporated to dryness and the residue [i.e. crude 2-(1'-carbethoxycyclopropyl)benz[e]isoindoline] was dissolved in THF (150 ml) and added to lithium aluminium hydride (10 g) in THF (100 ml) over 0.5 h. Water was then added and the resultant slurry was filtered and the filtrate was evaporated to dryness; the residue was partitioned between ether and water and the ether layer was extracted with concentrated hydrochloric acid. The acidic extract was evaporated to dryness to give a residue which was recrystallized from iso-propanol/ethyl acetate to give the title compound (5.9 g. m.p.192). | 

 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With sodium tris(acetoxy)borohydride; sodium hydrogencarbonate; In dichloromethane; | [Referential Example 239] (1R*,2S*)-N,N-Bis(tert-butoxycarbonyl)-4-[(1-ethoxycarbonyl)cyclopropan-1-yl]amino-1,2-cyclohexanediamine (Stereoisomer A and Stereoisomer B): Ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong> (1.63 g) was dissolved in dichloromethane (60 ml), and (1R*,2S*)-N,N-bis(tert-butoxycarbonyl)-4-oxo-1,2-cyclohexanediamine (3.0 g) and sodium triacetoxyborohydride (2.51 g) were added to stir the mixture at room temperature for 3 hours. An aqueous solution of sodium hydrogencarbonate was added to separate an organic layer. The organic layer was dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography on silica gel (hexane:ethyl acetate = 3:1 ? 1:1) to obtain the title compounds (Stereoisomer A: 1.43 g and Stereoisomer B: 2.17 g) as colorless amorphous solids. Stereoisomer A: 1H-NMR (CDCl3) delta: 0.90-1.00(1H,m), 1.05-1.15(1H,m), 1.20-1.85(29H,m), 2.00-2.10(1H,m), 3.20-3.35(2H,m), 3.65-3.75(1H,m) 4.11(2H,q,J=7.1Hz), 4.75-4.95(2H,m). MS (FAB) m/z: 442(M+H)+. Stereoisomer B: 1H-NMR (CDCl3) delta: 0.90-1.70(29H,m), 1.85-1.95(1H,m), 1.95-2.10(1H,m), 2.20-2.30(1H,m), 2.85-2.95(1H,m) 3.20-3.45(2H,m), 4.13(2H,q,J=7.1Hz), 4.80-4.95(2H,m). MS (FAB) m/z: 442(M+H)+. | 
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
 [ 194086-61-8 ]
                                                    
                                                    [ 194086-61-8 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 354 mg (28%) | With triethylamine; In sodium hydroxide; ethanol; | Example 8 1-(6-Chloro-1,1-dioxo-1,4-dihydro-thieno[3,2-e]-1lambda6,2,4-thiadiazin-3-ylamino)-cyclopropanecarboxylic acid A mixture of 3,6-dichloro-4H-thieno[3,2-e]-1,2,4-thiadiazine 1,1-dioxide (1.0 g, 3.9 mmol), <strong>[42303-42-4]1-aminocyclopropanecarboxylic acid ethyl ester hydrochloride</strong> (1.29 g, 7.8 mmol) and triethylamine (1.1 ml, 7.8 mmol) in ethanol (6 ml) was stirred for 23 h at 120 C. in a sealed flask. The cooled solution was concentrated in vacuo and the residue was triturated with water followed by adjustment to pH <2 with 4M hydrochloric acid. The resulting crude dark material was isolated by filtration and boiled in 1N sodium hydroxide followed by treatment with decolourising charcoal. After filtration, the solution was acidified to pH <2 with 4M hydrochloric acid and the precipitate was filtered off and recrystallized from ethanol to give 354 mg (28%) of the title compound; mp 299-300 C. (dec.); 1H-NMR (DMSO-d6): delta1.17 (br s, 2H), 1.49 (br s, 2H), 7.09 (s, 1H), 8.1 (br s, 1H), 11.15 (br s, 1H), 12.7 (br s, 1H); MS: m/e 303/305 (M-H2O)+. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 77% | b) 6-(2-Bromo-5-chloro-4-fluoro-phenV«-4,6-diaza-spiro(at)2.41hentane-5,7-dione; To a solution of 2-bromo-5-chloro-4-fluoroaniline (0.6 g, 2.7 mmol) and triethylamine (0.93 ml, 6.7 mmol) in 20 ml chloroform is added triphosgene (0.32 g, 1.07 mmol) in one portion. After stirring at room temperature for 5 hours first triethylamine (0.45 ml, 3.2 mmol) then 1- aminocyclopropane-1-carboxylic acid ethyl ester x HCI (0,44g, 2.7 mmol) and the mixture is stirred at 65 C for 16 hours. The crude product obtained after aquous workup is dissolved in 20 ml dioxane, potassium carbonate (0.37 g, 2.7 mmol) is added and the mixture heated to 120 C for 16 hours. Addition of water, extraction with ethylacetate, drying and concentration gave the crude hydantoin which is further purified by RP-HPLC to yield 0.69 g (2.1 mmol, 77%) of the title compound. 1 H-NMR (400MHz; DMSO-d6), 8 (ppm) : 1.37 (s, 4H), 7.97 (d, 1 H), 8.04 (d, 1H), 8.71 (s, 1 H). MS (m/z) ESI+: 333 (100, MH+). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With sodium tris(acetoxy)borohydride; In 1,2-dichloro-ethane; at 80℃; for 1.5h; | To a solution of 3-{5-[2-(methoxymethyl)-2'-methylbiphenyl-4-yl]-1 ,2,4-oxadiazol-3- yl}benzaldehyde, obtained in step 2, (125 mg; 0.33 mmol) in 1 ,2 DCE (1 .25 mL) was added 1-aminocyclopropane-1 -carboxylic acid ethyl ester hydrochloride (70 mg; 0.42 mmol) followed by sodium triacetoxyborohydride (1 10 mg; 0.52 mmol). The reaction was heated at 80C for 1 h30. The reaction was cooled down; DCM was added, the organic phase were washed with NaHCO3 sat. sol, dried on MgSO4, filtered off and concentrated. The crude material was purified by flash chromatography (EtOAc/cHex) to afford the title compound as a colorless oil. 1H NMR: (DMSO-d6, 300 MHz) delta 8.32 (m, 1 H), 8.17 (dd, J=1.9 Hz, 7.9 Hz, 1 H), 8.07 (brs, 1 H), 7.98 (m, 1 H), 7.54 (m, 2H), 7.42 (d, J=7.9 Hz, 1 H), 7.38-7.25 (m, 3H), 7.15 (m, 1 H), 4.23 (d, J=12.7 Hz, 1 H), 4.17 (d, J=12.7 Hz, 1 H), 4.09 (q, J=7.2 Hz, 2H), 3.94 (d, J=6.6 Hz, 2H), 3.25 (s, 3H), 2.04 (s, 3H), 1.22 (t, J=7.2 Hz, 3H), 1.15 (m, 2H), 0.96 (m, 2H). LC/MS (Method B): 498.3 (M+H)+ no (M-H)". HPLC (Method A) Rt: 4.55 min (purity: 93.4%). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 97% | With triethylamine; In dichloromethane; at 23℃; | To a solution of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (3.22 g, 19.4 mmol) in DCM (35 mL) was added triethylamine (2.71 mL, 19.4 mmol) upon which a suspension was obtained. A solution of Boc2O (4.24 g, 19.4 mmol) in DCM (5 mL) was added dropwise over ca. 2 mm. The reaction mixturewas stirred at RT overnight. Aqueous I M KHSO4 (100 mL) and DCM (50 mL) were added. The organic layer was separated, dried (Na2SO4), evaporated under reduced pressure and co-evaporated with THF (2x), to afford 4.31 g (97%) of the desired product. | 
| With sodium carbonate; In tetrahydrofuran; at 20℃; for 16h; | Step 1: Ethyl 1-(methylamino)cyclopropane-1-carboxylate A 2 M solution of sodium carbonate (15 mL of 2 M, 29.89 mmol) was added to a mixture of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (1.65 g, 9.963 mmol) in THF followed by the addition of di-tert-butyl dicarbonate (3.3 g, 14.94 mmol). The reaction was stirred for 16 hours at room temperature. Diethyl ether (50 mL) was added to the reaction and the aqueous layer separated. The organic layer was washed with 1N HCl (10 mL), water (10 mL) and brine, dried over MgSO4, filtered, and evaporated in vacuo to afford a clear oil. The clear oil was dissolved in THF and cooled to 0 C. Sodium hydride (1.2 g, 49.82 mmol) was added in portions wise. After 30 minutes, iodomethane (1.9 mL, 30 mmol) was added and the reaction was warmed to room temperature. A solution of saturated ammonium chloride (20 mL) was added and the reaction extracted with diethyl ether (3*20 mL). The combined organic extracts were washed with brine, dried over MgSO4, and concentrated to give ethyl 1-((tert-butoxycarbonyl)(methyl)amino)cyclopropane-1-carboxylate as a clear liquid, wt. 3.7 g. 1H NMR (400 MHz, CDCl3) delta 4.21-4.13 (m, 2H), 2.90-2.84 (m, 3H), 1.53-1.48 (m, 9H), 1.46 (d, J=8.0 Hz, 5H), 1.26 (d, J=7.0 Hz, 2H). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate; N-ethyl-N,N-diisopropylamine; In N,N-dimethyl-formamide; at 20℃; | Example EX7; 1-({3'-[1-(4-Chloro-3-methyl-phenyl)-ethylamino]-3,5-dimethyl-biphenyl-4-carbonyl}-amino)-cyclopropanecarboxylic acid; (1) 1-[(3'-Amino-3,5-dimethyl-biphenyl-4-carbonyl)-amino]-cyclopropanecarboxylic acid ethyl ester, INT11; To a solution of INT1 (600 mg, 2.49 mmol) and <strong>[42303-42-4]1-amino-cyclopropanecarboxylic acid ethyl ester hydrochloride</strong> (535 mg, 3.23 mmol) in DMF (12.5 mL) was added DIPEA (1.30 mL, 7.46 mmol) followed by TBTU (958 mg, 2.98 mmol) and the resulting mixture was stirred at room temperature overnight. The DMF was evaporated under reduced pressure and the residue dissolved in EtOAc. The organic layer was washed with 5% aqueous sodium bicarbonate, brine/water (1:1) and brine, dried over sodium sulfate, filtered and concentrated. The residue was purified by chromatography on silica gel (cyclohexane/EtOAc) to give INT11 as a white solid.LC/MS method 2: MS (ESI): 353 [M+H]+, rt=1.90 min. 1H-NMR (DMSO-d6): delta (ppm) 8.91 (s, 1H), 7.20 (s, 2H), 7.07 (t, 1H), 6.80 (t, 1H), 6.73 (d, 1H), 6.54 (dd, 1H), 5.13 (s, 2H), 4.10 (q, 2H), 2.28 (s, 6H), 1.43 (q, 2H), 1.20 (t, 3H), 1.10 (q, 2H). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With N-ethyl-N,N-diisopropylamine; In tetrahydrofuran; at 20℃; | Example EX81; 1-({3'-[(R)-1-(4-Chloro-3-methyl-phenyl)-ethylamino]-3,5-dimethyl-biphenyl-4-carbonyl}-methyl-amino)-cyclopropanecarboxylic acid; (1) 1-(4-Bromo-2,6-dimethyl-benzoylamino)-cyclopropanecarboxylic acid ethyl ester, INT36; To a suspension of 4-bromo-2,6-dimethyl-benzoic acid (864 mg, 3.77 mmol) in DCM (19 mL) a few drops of DMF and thionyl chloride (0.561 mL, 7.44 mmol) were added and the resulting mixture was refluxed for 1 hour. The mixture was then concentrated under reduced pressure and taken up in THF (19 mL). DIPEA (3.49 mL, 18.87 mmol) was then added, followed by ethyl 1-amino-1-cyclopropanecarboxylate hydrochloride (1.25 g, 7.44 mmol) and the mixture was stirred at room temperature overnight. The mixture was diluted in EtOAc, washed with 1M HCl, saturated aqueous sodium bicarbonate and brine, dried over sodium sulfate, filtered and concentrated. The residue was purified by chromatography on silica gel (cyclohexane/EtOAc) to give INT36 as a white foam.LC/MS method 2: MS (ESI): 340 [M+H]+, rt=2.19 min. 1H-NMR (DMSO-d6): delta (ppm) 8.94 (s, 1H), 7.27 (s, 211, 4.08 (q, 2H), 2.22 (s, 6H), 1.42 (q, 2H), 1.18 (t, 3H), 1.09 (q, | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With N-ethyl-N,N-diisopropylamine; In tetrahydrofuran; at 20℃; for 2h; | (4) 1-({3'-[(R)-1-(4-Chloro-3,5-dimethyl-phenyl)-ethylamino]-3,5-dimethyl-biphenyl-4-carbonyl}-amino)-cyclopropanecarboxylic acid ethyl ester, INT49; A solution of the hydrochloride INT48 (99 mg, 0.223 mmol) in 1 ml of DCM and one drop of DMF was treated with thionyl chloride (33 mul, 0.446 mmol). The solution was stirred at 50 C. for 30 minutes, then evaporated and dried under high vacuum for 10 minutes. The crude foam was then dissolved in 2 ml of THF and 1-amino-cyclopropyl-1-carboxylic acid ethyl ester hydrochloride (40.6 mg, 0.245 mmol) and DIEA (0.117 ml, 0.668 mmol) were added sequentially. This mixture was stirred at room temperature for 2 hours. The solvents were then evaporated and the crude was dissolved in 20 ml of ethyl acetate. The organic layer was washed with 0.2N-HCl, 10% sodium carbonate and brine, dried over sodium sulfate, filtered and evaporated. The crude was purified by chromatography on silica gel using cyclohexane and ethyl acetate (from 0% to 15%).UPLC: rt=2.52 min. MS (ESI): 519 [M+H]+, 1H-NMR (CDC)-d3): delta (ppm) 7.13 (t, 1H), 7.09 (br s, 4H), 6.83 (d, 1H), 6.68 (s, 1H), 6.48 (d, 1H), 6.15 (s, 1H), 4.41 (m, 1H), 4.22 (q, 2H), 2.38 (s, 6H), 2.36 (s, 6H), 1.69 (m, 2H), 1.50 (m, 2H), 1.22-1.32 (m, 6H). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; triethylamine; In N,N-dimethyl-formamide; at 20℃; | Benzoic acid, 1-hydroxybenzotriazole monohydrate, l-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and triethylamine were sequentially added to a mixed solution of 1-aminocyclopropane-l-carboxylic acid ethyl ester hydrochloride in N,N-dimethylformamide and water, and the mixture was stirred overnight at room temperature. A saturated aqueous ammonium chloride solution and water were added to the reaction solution, the resultant precipitate was obtained by filtration, and the obtained precipitate was dried to yield ethyl l-(benzoylamino)cyclopropanecarboxylate as a white powder | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| Step 1 : iPr2NEt (10 mL) was added into the solution of 2,4,6-trichloro-1,3,5-triazine (2.5 g) and 2,2,2-trifluoroethanol (1.36 g) in THF (100 mL). The reaction was stirred at room temperature for 16 hours before tert-butyl 4-aminobenzoate (2.62 g) was added. The resulting mixture was stirred at room temperature for 40 hours. Then, <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (2.25 g) was added into the mixture. The reaction was carried out at r.t. for 16 hours, then 115 C. for 16 hours. The reaction was quenched with water. The aqueous layer was extracted with EtOAc (3×100 mL). The combined organic layer was dried over Mg2SO4 and concentrated to offer a residue which will be purified by silica gel chromatography. | ||
| Step 1 : iPr2NEt (10 mL) was added into the solution of 2,4,6-trichloro-l,3,5-triazine (2.5 g) and 2,2,2-trifluoroethanol (1.36 g) in THF (100 mL). The reaction was stirred at room temperature for 16 hours before tert-butyl 4-aminobenzoate (2.62 g) was added. The resulting mixture was stirred at room temperature for 40 hours. Then, ethyl 1 -aminocyclopropanecarboxylate hydrochloride (2.25 g) was added into the mixture. The reaction was carried out at r.t. for 16 hours, then 1 15C for 16 hours. The reaction was quenched with water. The aqueous layer was extracted with EtOAc (3 x lOOmL). The combined organic layer was dried over Mg2S04 and concentrated to offer a residue which will be purified by silica gel chromatography. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 84% | With benzotriazol-1-ol; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; N-ethyl-N,N-diisopropylamine; In tetrahydrofuran; at 20℃; for 16h;Inert atmosphere; | Preparation 31 Ethyl 1-[(4-ethoxybenzoyl)amino]cyclopropanecarboxylate Combine 4-ethoxybenzoic acid (10.0 g, 60.18 mmol), <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (commercially available, 10.96 g, 66.19 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) (13.84 g, 72.21 mmol), and 1-hydroxybenzotriazole (HOBT) (9.76 g, 72.21 mmol) in tetrahydrofuran (500 mL). Add diisopropylethylamine (DIEA) (23.09 mL, 132.39 mmol) over 3-5 minutes and stir the reaction for approximately 16 hours at ambient temperature under nitrogen. Dilute the mixture with ethyl acetate, wash with dilute HCl, dilute NaHCO3, and then brine, dry over sodium sulfate, and concentrate the organic layer under reduced pressure. Purify the residue by recrystallization from ethanol to give the title compound (13.93 g, 84%) as a white solid: MS (m/z): 278 (M+1). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| Preparation 1 Ethyl 1-[(4-ethoxybenzoyl)amino]cyclopropanecarboxylate Add oxalyl chloride (189 mL, 2.17 mol) to 4-ethoxybenzoic acid (334.5 g, 1.99 mol) and N,N-dimethylformamide (1 mL) in dichloromethane (3 L). After 1 hr at 25-26 C., concentrate the mixture under reduced pressure until a constant weight is achieved. Stir <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (300 g, 1.81 mol) and dichloromethane (2.5 L) in an ice water bath. Add triethylamine (631 mL, 4.53 mol) and then add a solution of the acid chloride (ca 380 g) in dichloromethane (500 mL). Stir the reaction mixture for approximately 16 hours at ambient temperature. Dilute the reaction with aqueous 1N hydrochloric acid (1 L). Extract the aqueous layer with dichloromethane (1 L). Wash the organic layer with water (2 L) and brine (2 L). Dry the solution over sodium sulfate, filter, and concentrate under reduced pressure. Slurry the residue in hexanes and filter to give the title compound (478 g, 95%) as an ivory powder: MS (mass spectrometry) (m/z): 278 (M+1). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With triethylamine; In dichloromethane; at 20℃; for 16h; | Preparation 30 Ethyl 1-[[4-(cyclopropoxy)benzoyl]amino]cyclopropanecarboxylate To a 0 C. suspension of 4-cyclopropoxybenzoic acid (24.5 g, 137.3 mmol) in dichloromethane (350 mL) containing 2 drops of DMF, slowly add oxalyl chloride (23.8 mL, 274.7 mmol). After addition, remove the cooling bath and stir for 2 hours. Concentrate the material to dryness under reduced pressure. Dissolve the residue in dichloromethane (500 mL), and then add <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (Indofine #04-265, 24.9 g, 150.5 mmol) and triethylamine (57.2 mL, 410.4 mmol). Stir the mixture at ambient temperature for approximately 16 hours. Wash the mixture once with 10% NaHSO4 (250 mL). Separate the organic portion and extract the aqueous portion 2* with dichloromethane (200 mL). Combine the organic, dry over sodium sulfate, filter, and concentrate under reduced pressure. Purify the crude mixture by flash chromatography (0% to 45% EtOAc/Hex) to give the title compound (33.7 g, 85%): MS (m/z): 290 (M+1). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With dmap; triethylamine; In ethanol; at 20℃; | Example 15Synthesis of: 3-((l-((R)-2-amino-3-((R)-2,3- bis(dodecanoyloxy)propylthio)propanamido)cvclopropyl)methoxy)propylphosphonic acidStep 1: tert-but l l-(hydroxymethyl)cyclopropylcarbamate[000470] To a solution of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (1 eq) in EtOH (0.3 M) at room temperature was added di-½ri-butyl carbonate (1.5 eq), triethylamine (2 eq), and DMAP (0.05 eq). The reaction was stirred at room temperature overnight. The reaction mixture was concentrated en vaccuo; and the residue was diluted in ethyl acetate. The organic solution was washed 1: 1 saturated aqueous NH4Cl/water, brine, dried over anhydrous MgS04, and concentrated en vaccuo. The material was taken up in THF (0.3 M) and cooled to 0 C. To this solution was added 2 M LiBH4 in THF (4 eq). The reaction was warmed to room temperatureand stirred for 4 hours, at which time more 2 M LiBH4 (1.3 eq) was added, and stirred overnight. The reaction mixture was cooled to 0 C and slowly quenched with MeOH over 10 minutes and then water. The solution was stirred for 10 minutes; and precipitates appeared. The precipitates were filtered and rinsed with ethyl acetate. The filtrate was washed with water, brine, dried over anhydrous MgS04, and concentrated en vaccuo. The crude mixture was purified by flash chromatography on a COMBIFLASH system (ISCO) using a gradient of 0-75% ethyl acetate in hexanes to give the product. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| With triethylamine; In dichloromethane; at 20℃; | (1) A mixture of 600 mg of methyl 4-[2-(4-[(2-[3-(chlorosulfonyl)benzoyl]amino}-4,5,6,7-tetrahydro-1-benzothiophen-3-yl)carbonyl]amino}phenyl)ethyl]benzoate, 390 mg of ethyl 1-aminocyclopropane carboxylate hydrochloride, 0.27 mL of triethylamine, and 6.0 mL of dichloromethane was stirred at room temperature overnight, and then the reaction mixture was concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (hexane-chloroform) to obtain 523 mg of methyl 4-(2- {4-[({2-[(3-[1-(ethoxycarbonyl)cyclopropyl]sulfamoyl}benzoyl)amino]-4,5,6,7-tetrahydro-1-benzothiophen-3-yl}carbonyl)amino]phenyl}ethyl)benzoate as a pale yellow solid. ESI+: 730 | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 1.80 g | With pyridine; triethylamine; In dichloromethane; at 20℃; | (1) A mixture of 774 mg of <strong>[42303-42-4]ethyl 1-aminocyclopropane-1-carboxylate hydrochloride</strong>, 1.4 mL of triethylamine, and 15 mL of dichloromethane was stirred at room temperature for 30 minutes, and 15 mL of pyridine and 1.50 g of 2-(trimethylsilyl)ethyl 3-(chlorosulfonyl)benzoate were added thereto in this order, followed by stirring at room temperature overnight. The reaction mixture was concentrated under reduced pressure, and to the residue was added an aqueous citric acid solution, followed by extraction with ethyl acetate. The organic layer was washed with saturated brine, then dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (hexane-ethyl acetate) to obtain 1.80 g of 2-{trimethylsilyl)ethyl 3-[1-(ethoxycarbonyl)cyclopropyl]sulfamoyl}benzoate as a colorless oily substance. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 15% | DIAD (0.9 mL, 1 eq) in THF (2 mL) was added dropwise to a stirred solution containing (l-isopentyl-lH-benzo[d]imidazol-2-yl)methanol (1.0 g), RhoRho1¾ (1.2 g, 1 eq) and isatoic anhydride (748 mg, leq) in THF (30 mL) and stirred overnight. The reaction was concentrated to a light brown residue that was taken up in DMF (20 mL) and treated with <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (1.05 g, 1.5 eq) and heated to 75C for 48 h. Aqueous workup between Et20 and water gave a brown foam (11.2 g) . This crude ester was dissolved in 2 M NaOH / EtOH (4: 1, 10 mL) and warmed to 70C for 5 h. The cooled reaction was concentrated, taken up in 2M NaOH and washed with Et20. The aqueous phase was acidified to pH 4 with 2M HCl and extracted into EtOAc (2 x 25 mL). This gave an impure brown foam which was purified on silica gel with isohexane / EtOAc (3:1 to 1 :1) as eluant. This gave the desired acid as the more polar component as a cream solid (279mg, 15%). ? NMR (400 MHz, DMSO): delta 8.85 (1H, s), 8.8 (1H, t), 7.58 (1H, d), 7.48 (1H, d),7.349 (1H, dd), 7.18 (3H, m), 6.93 (1H, d), 6.55 (1H, t), 4.68 (2H, d), 4.29 (2H, m), 1.67 (1H, sept), 1.578 (2H, m), 1.085 (2H, m), 0.94 (8H, d). LC/MS 421.5 (MH+). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 30 mg | In dichloromethane; at 20℃; for 72h; | Example 1841- i1-(3-Benzoyl-4-chloro-2-fluorophenyl)-propylamino1-cvclopropanecarboxylic acid amide.HCI Step 1A solution of [3-(1-bromopropyl)-6-chloro-2-fluorophenyl]-phenyl-methanone (75 mg;0.14 mmol), triethylamine (90 ??; 2.5 equiv.) and 1-amino-cyclopropane-1-carboxylic acid ethyl ester. HCI (30 mg; 1.2equiv.) in DCM (3 ml) was stirred at room temperature for 72 hours then partitioned between EtOAc and brine. The EtOAc later was separated, dried (Na2S04), filtered and evaporated. The crude material was purified by flash column chromatography using gradient elution from 0-50% EtOAc / petroleum ether. Product containing fractions were combined and evaporated to give 30 mg of 1-[1-(3-benzoyl-4-chloro-2-fluorophenyl)-propylamino]-cyclopropanecarboxylic acid ethyl ester as a white solid. | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 76% | With pyridine; 1-ethyl-(3-(3-dimethylamino)propyl)-carbodiimide hydrochloride; at 20℃; for 3h;Inert atmosphere; | To the suspension of 3-nitrobenzoic acid ( 1 g, 5.98 mmol) in pyridine ( 10ml) <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> ( 1.090 g, 6.58 mmol) was added followed by EDC.HC1 (1.721 g, 8.98 mmol) under nitrogen. Reaction mixture was stirred at room temperature for 3hrs. Reaction mixture was diluted with cold water ( 100ml) and extracted with ethyl acetate (2X25ml). Separated organic layer was washed with brine and water, dried over sodium sulfate and concentrated under vacuum till dryness to obtain product ( 1.26g, 76%). NMR (400 MHz, CDC13) 8 (ppm): 8.59 (bs, 1H), 8.41-8.38 (m, 1H), 8.20-8. 18(m, 1H), 7.68 (t, 1H, J=8Hz), 6.82 (bs, 1H), 4.19 (q, 2H, J=7.2Hz), 1.70- 1.34 (m, 2H), 1.37- 1.33 (m, 2H), 1.26(t,3H,J=7.2Hz). ESI- MS (m/z): 279.58 (M+l) | 
 [ 50-00-0 ]
                                                    
                                                    [ 50-00-0 ]
 [ 131543-46-9 ]
                                                    
                                                    [ 131543-46-9 ]
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 350 mg | Step 1 : Ethyl 1 -(1 H-imidazol-1 -yl)cyclopropanecarboxylate Ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong> (850 mg, 6.58 mmol), phosphoric acid (85%, 0.2 mL), glyoxal (40%, 0.76 mL) and formaldehyde (37%, 0.5 mL) in water (4 mL) were stirred for 15 min at room temperature. The reaction mixture was then heated to 90C followed by the addition of ammonium chloride (354 mg) in water (3 mL). The resulting mixture was stirred at 90C for 1 h. The mixture was cooled to room temperature and was neutralized using aqueous potassium hydroxide (3N) at 10C. The solvent was removed under reduced pressure and co-distilled with toluene. The crude material was purified via column chromatography (100-200 mesh silica gel, 0-5% methanol in dichloromethane) to afford ethyl 1 -(1 H-imidazol-1- yl)cyclopropanecarboxylate (350 mg). | 
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 64% | With bis-(2-oxo-3-oxazolidinyl)phosphoryl chloride; N-ethyl-N,N-diisopropylamine; In 1,2-dimethoxyethane; at 60℃; for 1h; | Step 1: Ethyl 1-(1-benzyl-3-(4-chlorophenyl)-4-methyl-5-(trifluoromethyl)-1H-pyrrole-2-carboxamido)cyclopropanecarboxylate BOP-CI (776 mg, 3.05 mmol) was added to ACI-03 (1.00 g, 2.54 mmol), DIPEA (1.77 mL, 10.2 mmol) and <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (0.631 g, 3.81 mmol) in DME (10 mL). The reaction mixture was stirred at 60 C. for 1 h, after which the reaction mixture was allowed to cool to room temperature. The reaction mixture was diluted with EtOAc, washed with aqueous 1M KHSO4 and saturated aqueous NaHCO3, dried (Na2SO4) and concentrated. The residue was purified by crystallisation (EtOAc/heptane) to give the desired product (821 mg, 64%). | 
| 64% | With bis-(2-oxo-3-oxazolidinyl)phosphoryl chloride; N-ethyl-N,N-diisopropylamine; In 1,2-dimethoxyethane; at 60℃; for 1h; | Step 1: Ethyl I -(I -benzyl-3-(4-chlorophenyl)-4-methyl-5-(trifluoromethyl)-1 H-pyrrole-2- carboxamido)cyclopropanecarboxylateBOP-CI (776 mg, 3.05 mmol) was added to ACI-03 (1.00 g, 2.54 mmol), DIPEA (1.77 mL, 10.2 mmol) and <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (0.631 g, 3.81 mmol) in DME (10 mL). The reaction mixture was stirred at 60 C for I h, after which the reaction mixture was allowed to cool to room temperature. The reaction mixture was diluted with EtOAc, washed with aqueous 1 M KHSO4 and saturated aqueous NaHCO3, dried (Na2SO4) and concentrated. The residue was purified by crystallisation (EtOAc/heptane) to give the desired product (821 mg, 64%). | 
 [ 709650-48-6 ]
                                                    
                                                    [ 709650-48-6 ]
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 48% | Step-(ii): Synthesis of ethyl 1-4(2-amino-5-bromopyridin-3-yl)methyl)amino)cyclopropane carboxylate (U) To a stirred solution of ethyl-<strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong> (9.77 g, 59.21 mmol) in methanol (100 mL) were added triethylamine (15.46 mL, 111.18 mmol) and 2-amino-5-bromonicotinaldehyde hydrobromide (T) (10.3 g, 36.78 mmol) at 0 C. and the reaction mixture was allowed to stir at 20-35 C. for 16 h. Then sodium cyano-borohydride (7 g, 111.39 mmol) was added at 0 C. and the reaction mixture was allowed to stir at 20-35 C. for another 16 h. The reaction mixture was rotary evaporated under vacuum and the resultant residue was diluted with water (200 mL) and extracted with ethyl acetate (2*200 mL). The organic layer was washed with brine (100 mL), dried over anhydrous Na2SO4 and filtered. The filtrate was rotary evaporated under vacuum to get residue which was purified by column chromatography using mixture of 4% methanol/dichloromethane as an eluent to get the desired compound as a brown waxy solid (5.6 g, 48%); 1H NMR (400 MHz, DMSO-d6) delta 7.89 (d, J=2.4 Hz, 1H), 7.44 (d, J=2.0 Hz, 1H), 6.16 (bs, 2H), 4.13-4.03 (m, 2H), 3.59 (d, J=4.4 Hz, 2H), 2.92-2.84 (m, 1H), 1.24-1.14 (m, 5H), 1.04-0.98 (m, 2H); LC-MS: 314.3 (M+1)+. | |
| 48% | To a stirred solution of ethyl- <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong> (9.77 g, 59.21 mmol) in methanol (100 mL) were added triethylamine (15.46 mL, 111.18 mmol) and 2-amino-5-bromonicotinaldehyde hydrobromide (T) (10.3 g, 36.78 mmol) at 0C and the reaction mixture was allowed to stir at 20-35C for 16h. Then sodium cyano- borohydride (7 g, 111.39 mmol) was added at 0C and the reaction mixture was allowed to stir at 20-35 C for another 16 h. The reaction mixture was rotary evaporated under vacuum and the resultant residue was diluted with water (200 mL) and extracted with ethyl acetate (2x200 mL). The organic layer was washed with brine (100 mL), dried over anhydrous Na2S04 and filtered. The filtrate was rotary evaporated under vacuum to get residue which was purified by column chromatography using mixture of 4% methanol/dichloromethane as an eluent to get the desired compound as a brown waxy solid (5.6 g, 48%); NMR (400MHz, DMSO-<) delta 7.89 (d, J=2.4 Hz, 1H), 7.44 (d, J=2.0 Hz, 1H), 6.16 (bs, 2H), 4.13- 4.03 (m, 2H), 3.59 (d, J=4.4 Hz, 2H), 2.92-2.84 (m, 1H), 1.24-1.14 (m, 5H), 1.04-0.98 (m, 2H); LC-MS: 314.3 (M+l)+. | 
 [ 42303-42-4 ]
                                                    
                                                    [ 42303-42-4 ]
 [ 10429-82-0 ]
                                                    
                                                    [ 10429-82-0 ]
| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 47.8% | With N-ethyl-N,N-diisopropylamine; In ethanol; for 16h;Reflux; | A mixture of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (120 g, 0.725 mol), N,N- diisopropylethylamine (942 g, 7.29 mol), N-benzyl-2-chloro-N-(2-chloroethyl)ethanamine hydrochloride (213 g, 0.793 mol) in anhydrous ethanol (1.6 L) was stirred under reflux for 16 h. TLC (PE:EtOAc = 5:1,f= 0.4) showed that most of the starting material was consumed. Then the mixture was concentrated. The residue was partitioned between dichloromethane (1 L) and water (0.5 L). The layers were separated and the aqueous layer was extracted with dichloromethane (0.5 L x 2). The combined organic layers were concentrated. The residue was purified by chromatography on silica gel (PE:EtOAc = 20:1 to 10:1) to give ethyl l-(4-benzylpiperazin-l-yl)cyclopropanecarboxylate (100 g, 47.8%) as a light yellow oil.1H-NMR (400MHz, chloroform-di): delta [ppm] = 0.88-0.97 (m, 2H), 1.23-1.36 (m, 5H), 2.37 (br. S, 4H), 2.98 (br. S, 4H), 3.51 (s, 2H), 4.15 (q, 2H), 7.23-7.36 (m, 5H). | 
| 47.8% | With N-ethyl-N,N-diisopropylamine; In ethanol; for 16h;Reflux; | A mixture of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (120 g, 0.725 mol), N,N- diisopropylethylamine (942 g, 7.29 mol), N-benzyl-2-chloro-N-(2-chloroethyl)ethanamine hydrochloride (213 g, 0.793 mol) in anhydrous ethanol (1.6 L) was stirred under reflux for 16 h. TLC (PE:EtOAc = 5:1, Rf = 0.4) showed that most of the starting material was consumed. Then the mixture was concentrated. The residue was partitioned between dichloromethane (1 L) and water (0.5 L). The layers were separated and the aqueous layer was extracted with dichloromethane (0.5 L x 2). The combined organic layers were concentrated. The residue was purified by chromatography on silica gel (PE:EtOAc = 20:1 to 10:1) to give ethyl l-(4-benzylpiperazin-l-yl)cyclopropanecarboxylate (100 g, 47.8%) as a light yellow oil. 1H-NM (400MHz, chloroform-di): delta [ppm] = 0.88-0.97 (m, 2H), 1.23-1.36 (m, 5H), 2.37 (br. S, 4H), 2.98 (br. S, 4H), 3.51 (s, 2H), 4.15 (q, 2H), 7.23-7.36 (m, 5H). | 
| 43% | With N-ethyl-N,N-diisopropylamine; In ethanol; for 16h;Reflux; | A mixture of ethyl 1- aminocyclopropanecarboxylate hydrochloride (2.4 g, 14.5mmol), N-benzyl-2-chloro-N-(2- chloroethyl)ethanamine hydrochloride (4.26 g, 15.8 mmol), and N,N-Diisopropylethylamine (25 mL) in ethanol (32 mL) was stirred at reflux for 16 hours. The reaction mixture was concentrated to dryness. The residue was partitioned between dichloromethane and water. Two layers were separated, and the aqueous layer was extracted with dichloromethane. The combined organic layers were concentrated. The residue was purified by silica gel column (pet. ether/EtOAc = 1 :0-10: 1 ) to give ethyl l-(4-benzylpiperazin-l-yl)cyclopropanecarboxylate (1-61-2, 1.8 g, yield: 43%) as a yellow oil. 1H NMR (400 MHz, CDC13) delta: 7.37-7.27 (m, 5H), 4.19-4.13 (m, 2H), 3.54 (s, 2H), 3.00(brs, 2H), 2.39 (brs, 2H), 1.31-1.26 (m, 5H), 7.52 (m 1H), 0.93-0.91 (m, 2H). | 
| 24% | With sodium hydrogencarbonate; In ethanol; at 80℃; for 4h; | N-Benzyl-2-chloro-N-(2-chloroethyl)ethanamine hydrochloride (obtained in the previous step, 10.37 g, 38.61 mmol) was added to a solution of <strong>[42303-42-4]ethyl <strong>[42303-42-4]1-aminocyclopropanecarboxylate hydrochloride</strong></strong> (6.4 g, 38.6 mmol) and NaHCO3 (17.5 g, 208.5 mmol) in EtCH (200 mL). The reaction mixture was stirred at 80 C for 4 hand overnight at rt. The solvent was concentrated and the crude product was diluted with AcOEt and water. The layers were separated and the organic layer was driedover Na2SO4, filtered and concentrated. The crude residue was purified by flash chromatography on silica gel, eluents CH/AcOEt (100:0 to 0:100) to give the title compound (2.86 g, 24% yield).HPLC-MS (Method A): Ret, 2.26 mm; ESl-MS m/z, 289 (M÷1). | 

| Yield | Reaction Conditions | Operation in experiment | 
|---|---|---|
| 132 g | With hydrogenchloride; In ethyl acetate; at -30 - 0℃; for 0.5h; | Thionyl chloride (150 mL, 2.056 mol) was added slowly below 0 C to a suspension of 1- aminocyclopropanecarboxylic acid (100 g, 0.989 mol) in anhydrous ethanol (1 L). The mixture was stirred at 70 C for 20 h. TLC (methanol,f= 0.4) showed that most of the starting material was consumed. Then the solution was concentrated to give 210 g of crude product. The residue was dissolved in water and adjusted to a pH between 9 and 10 with potassium carbonate. The aqueous layer was extracted with dichloromethane (1 L x 3). The combined organic layers were concentrated to dryness. The residue was dissolved in ethyl acetate (300 mL) and hydrochloride in ethyl acetate (250 mL, 4M) was added slowly to the solution below -30 C. It was stirred for 30 min at 0 C. A solid precipitated and it was filtered under nitrogen atmosphere to give ethyl 1-aminocyclopropanecarboxylate hydrochloride (132 g, 80.6% yield) as a white solid.The following1H-NM is from the free amine.1H-NMR (400MHz, chloroform-di): delta [ppm] = 0.91-1.02 (m, 2H), 1.15-1.30 (m, 5H), 2.17 (s, 2H), 4.10 (d, 2H). |