Diisopropylethylamine → benzhydryl 1-[(Z)-[2-[[(2R,3S)-2-[[(5R)-5-[[(2-methylpropan-2-yl)oxycarbonylamino]methyl]-2-oxo-1,3-oxazolidin-3-yl]methyl]-4-oxoazetidin-3-yl]amino]-1-[2-[(2-methylpropan-2-yl)oxycarbonylamino]-1,3-thiazol-4-yl]-2-oxoethylidene]amino]oxycyclopropane-1-carboxylate

Participants

Reaction Steps

To a solution of (Z)-2-((1-((benzhydryloxy)carbonyl)cyclopropoxy)imino)-2-(2-((tert-butoxycarbonyl)amino)thiazol-4-yl)acetic acid (1.29 g, 2.28 mmol) and HATU (909 mg, 2.39 mmol) in DMF:DCM (3:1, 9.0 mL) at 0° C. was added DIPEA (1.0 mL, 5.72 mmol). After 15 min of stirring at 0° C. tert-butyl (((R)-3-(((2R,3S)-3-amino-4-oxoazetidin-2-yl)methyl)-2-oxooxazolidin-5-yl)methyl)carbamate (715 mg, 2.28 mmol) was added as a solution in DMF:DCM (1:1, 9 mL) followed by a DMF (1.5 mL) wash. After 1.2 h at rt it was diluted with EtOAc and washed with LiCl (5% aq). The aqueous layer was extracted with EtOAc (3×) and the combined organic layers were washed with LiCl (5% aq), NaHCO3 (aq satd), brine, dried over Na2SO4 and concentrated in vacuo. The crude residue was purified via silica gel chromatography (EtOAc-Heptane, 5-90%) to afford the title compound (1.357 g, 72%) as a white solid. LCMS: Rt=1.04 min, m/z=834.4 (M+1) Method 2m_acidic.

Provenance & Evidence