C(OC([NH:8][C:9]1[CH:16]=[CH:15][C:12]([C:13]#[N:14])=[CH:11][CH:10]=1)=O)(C)(C)C.O1CC(=O)N=N1.C(OC(=O)CCNC(=O)C1C=CC(C2[NH:38][O:39][C:40](=[O:42])N=2)=CC=1)C>C(Cl)Cl.C(O)(C(F)(F)F)=O>[O:39]1[C:40](=[O:42])[N:14]=[C:13]([C:12]2[CH:11]=[CH:10][C:9]([NH2:8])=[CH:16][CH:15]=2)[NH:38]1Compound 14 (3.25 g, 14.9 mmol) was converted into oxadiazolone 15 as described earlier for the preparation of compound 3. The resulting crude light orange solid was stirred for 5 h in a mixture of DCM (15 mL) and TFA (8 mL). Concentration under reduced pressure and evaporation with toluene (2×10 mL) gave a brown solid which was purified by silica gel (40 g) column chromatography (eluent: EtOAc) to yield compound 16 (1.81 g, 69% over the three steps). Rf 0.5 (EtOAc).
Wird geladen…
