Piperidine → 4-[(S)-2-Amino-5-({amino-[(E)-2,2,4,6,7-pentamethyl-2,3-dihydro-benzofuran-5-sulfonylimino]-methyl)-amino)-pentanoyl]-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of compound T (46.2 mmol) in EtOAc (175 mL) at room temperature was added piperidine (4.57 mL, 46.2 mmol) and the reaction mixture was stirred for 18 h at room temperature. Next the solvent was removed in vacuo and the resulting residue dissolved in minimum amount of EtOAc (˜50 mL) and hexane (˜1 L) was added. Precipitated crude product was filtered off and recrystallised again with EtOAc (˜30 mL) and hexane (˜750 mL). The precipitate was filtered off, washed with hexane and dried in vacuo to afford compound U (28.0 g, 46.2 mmol). LC-MS [M+H] 595.4 (C28H46N6O6S+H, calc: 595.3).

Provenance & Evidence