L-tert-Leucine → 3-Hydroxy-2-(4-methoxyphenyl)-2,3-dihydro-1,5-benzothiazepin-4(5H)-one, (2S,3S)-

Participants

Reaction Conditions

Reaction Steps

A mixture of L-tert-leucine (433 mg), lithium borohydride (65.4 mg) and tetrahydrofuran (28 ml) is refluxed under nitrogen atmosphere for one hour. The mixture is cooled to -10° C., and thereto is added 2-(4-methoxyphenyl)-1,5-benzothiazepine-3,4(2H,5H)-dione (299 mg), and the mixture is further stirred at -10° C. for 15 hours. The mixture is evaporated under reduced pressure to remove the solvent, and to the residue is added 1N hydrochloric acid (10 ml). The precipitated crystal is collected by filtration, washed with water, and dried to give (2S,3S)-3-hydroxy-2-(4-methoxyphenyl)-2,3-dihydro-1,5-benzothiazepin-4(5H)-one (282 mg).

Provenance & Evidence