反应详情

A solution of (8S,11R,15R)-11-(((9H-fluoren-9-yl)methoxy)carbonylamino)-8-ethyl-2,2-dimethyl-4,10-dioxo-3,6-dioxa-13-thia-9-azahexadecane-15,16-diyl didodecanoate (1 eq, from the previous step) in 50% TFA in DCM (0.05 M) was stirred in open air at 40° C. for 1.5 hours. The mixture was dried under a stream of air and briefly evaporated under high vacuum. The resulting oil was dissolved in 20% piperidine in THF (0.1 mL) and stirred at room temperature for 1 hour. The reaction mixture was diluted with ethyl acetate. The reaction mixture was concentrated en vaccuo. The crude mixture was purified by flash chromatography on a COMBIFLASH® system (ISCO) using a gradient of 0-10% methanol in DCM to give the product as a solid. 1H NMR (DMSO-d6): δ 8.30 (d, 1H), 5.11 (m, 1H), 4.27 (dd, 1H), 4.09 (dd, 1H), 3.96 (s, 2H), 3.67-3.76 (m, 2H), 3.37-3.48 (m, 2H), 2.71-2.95 (m, 4H), 2.25-2.28 (m, 4H), 1.23-1.62 (m, 41H), 0.83-0.88 (m, 6H). LRMS [M+H]=689.4.

1. customThe mixture was dried under a stream of air
2. custombriefly evaporated under high vacuum
3. dissolutionThe resulting oil was dissolved in 20% piperidine in THF (0.1 mL)
4. additionThe reaction mixture was diluted with ethyl acetate
5. concentrationThe reaction mixture was concentrated en vaccuo
6. customThe crude mixture was purified by flash chromatography on a COMBIFLASH® system (ISCO)