Diisopropylethylamine → tert-butyl 2-methyl-2-[(Z)-[2-[[(2R,3S)-2-[[5-[[(2-methylpropan-2-yl)oxycarbonylamino]methyl]tetrazol-1-yl]methyl]-4-oxoazetidin-3-yl]amino]-1-[2-[(2-methylpropan-2-yl)oxycarbonylamino]-1,3-thiazol-4-yl]-2-oxoethylidene]amino]oxypropanoate

Participants

Reaction Steps

Prepared in an analogous manner to example 4, step 3 using (Z)-2-(((1-(tert-butoxy)-2-methyl-1-oxopropan-2-yl)oxy)imino)-2-(2-((tert-butoxycarbonyl)amino)thiazol-4-yl)acetic acid (214 mg, 0.498 mmol), DIPEA (953 μL, 5.46 mmol) and HATU (830 mg, 2.18 mmol) in DCM:DMF (5:1, 3.6 mL) at 0° C. followed by a solution of tert-butyl ((1-(((2R,3S)-3-amino-4-oxoazetidin-2-yl)methyl)-1H-tetrazol-5-yl)methyl)carbamate (123 mg, 0.415 mmol) in DCM:DMF (4.3:1, 3.7 mL). After stirring at rt for 1 h it was subjected to an identical workup then purified via silica gel chromatography (Acetone-DCM), affording the title compound (174 mg, 59%) as a light purple solid. LCMS: Rt=1.03 min, m/z=709.2 (M+1) Method 2m_acidic.

Provenance & Evidence