* 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.
With triethylamine; In acetonitrile; at 40℃;Inert atmosphere;
(1) preparative example of (2S,4S)-2-[(4-aminosulfonylphen-1-yl)iminomethylformyl]-4-thiol-1-(p-nitrobenzyloxycarbonyl)pyrrolidine (intermediate 1) 5-N-(4-nitrobenzyloxycarbonyl)-2-thia-5-azabicyclo[2.2.1]hept-3 -one (raw material 1) (1600 g, 5.19 mol) and <strong>[13009-99-9]mafenide acetate</strong> (raw material 2) (1219.2 g, 4.95 mol) were dissolved in acetonitrile, and the solution was warmed to 40 C. Triethylamine was added dropwise under nitrogen protection, and the reaction mixture was stirred to precipitate, filtered to obtain intermediate 1.
With triethylamine; In acetonitrile; at 40℃;Inert atmosphere; Large scale;
Intermediate 1 is (2S,4S)-2-[(4-aminosulfonylphen-1-yl)iminomethylformyl]-4-thiol-1-(p-nit robenzyloxycarbonyl)pyrrolidine. 5-N-(4-nitrobenzyloxycarbonyl)-2-thia-5-azabicyclo[2.2.1]hept-3-one (raw material 1) (1600 g, 5.19 mol) and <strong>[13009-99-9]mafenide acetate</strong> (raw material 2) (1219.2 g, 4.95 mol) were dissolved in acetonitrile, and the solution was warmed to 40 C. Triethylamine was added dropwise under nitrogen protection, and the reaction mixture was stirred to precipitate, filtered to obtain intermediate 1.
(4R,5S,6S)-3-[[(3S,5S)-N-(4-nitrobenzyloxycarbonyl)-5-[(4-aminosulfonylphen-1-yl)methyl]carbamoyl]-3-pyrrolidinyl]thio-6-[(R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid(4-nitrobenzyl) methyl ester[ No CAS ]
[(4R,5S,6S)-3-[(3S,5S)-5-[(4-aminosulfonylphen-1-yl)methyl]carbamoyl]-3-pyrrolidinyl]thio-6-[(R)-1-hydroxyethyl]-4-methyl-7-oxo-1-azabicyclo [3.2.0]hept-2-ene-2-carboxylic acid[ No CAS ]
tert-butyl 6-(4-sulfamoylbenzylamino)-2-azaspiro[3.3]heptane-2-carboxylate[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
To a stirred solution of tert-butyl 6-oxo-2- azaspiro[3.3]heptane-2-carboxylate (200 mg, 0.946 mmol, 1 eq) in methanol (5 ml) was added 4-(aminomethyl)benzenesulfonamide acetate (282 mg, 1.13 mmol, 1.2 eq) and the reaction mixture was stirred at RT for overnight. To the reaction mixture, NaBH4 (54 mg, 1.41 mmol, 1.5 eq) was added at 0oC and then resultant reaction mixture was allowed to stir at 0oC for 1h. Progress of reaction was monitored by TLC. After completion, reaction mixture was concentrated under reduced pressure to get residue which was diluted with water (50 mL) and extracted with dichloromethane (2 × 50 mL). Combined organic layer was dried over anhydrous sodium sulfate. Removal of solvent under reduced pressure to afford tert- butyl 6-(4-sulfamoylbenzylamino)-2-azaspiro[3.3]heptane-2-carboxylate (310 mg, 85.87%) which was used in the next step without purification.