2(R,S)-methoxyethyl-3,4-dihydro-2H-1,4-benzoxazine → 5(S)-Amino-4(S)-hydroxy-2(R),7,7-trimethyl-8-[2(R,S)-methoxyethyl-3,4-dihydro-2H-1,4-benzoxazin-4-ylcarbonyl]-octanoic acid (N-butyl)amide

Participants

Reaction Steps

Starting from 230 mg of 3-[N-tert-butoxycarbonyl-4(S)-(3-carboxy-2,2-dimethylpropyl)-2,2-dimethyl-1,3-oxazolidin-5(S)-yl]-2(R)-methyl-propionic acid (N-butyl)amide and 193 mg of 2(R,S)-methoxyethyl-3,4-dihydro-2H-1,4-benzoxazine, the title compound is obtained via (4O,5N-isopropylidene)-5(S)-tert-butoxycarbonylamino-4(S)-hydroxy-2(R),7,7-trimethyl-8-[2(R,S)-methoxyethyl-3,4-dihydro-2H-1,4-benzoxazin-4-ylcarbonyl]-octanoic acid (N-butyl)amide (analogously to Example 1a); Rf (A)=0.19; Rt (VI)=36.6/36.9 min) and 5(S)-tert-butoxycarbonylamino-4(S)-hydroxy-2(R),7,7-trimethyl-8-[2(R,S)-methoxyethyl-3,4-dihydro-2H-1,4-benzoxazin-4-ylcarbonyl]-octanoic acid (N-butyl)amide (Rf (X)=0.36; Rt (VI)=30.6 min; FAB-MS: (M+H)+ =592) in a manner analogous to that described in Example 1) as a diastereomer mixture:Rf (V)=0.32; Rt (VI)=23.7/24.1 min; FAB-MS: (M+H)+ =492.

Provenance & Evidence