反应详情

To a solution of 3,4-bis(ethyloxy)benzoic acid (631 mg) in tetrahydrofuran (15 mL) stirred at room temperature was added EDCI (767 mg) and HOBT (613 mg). The reaction mixture was stirred for 2 h. Then ethyl 3-{7-[(Z)-(hydroxyamino)(imino)methyl]-1H-indol-3-yl}propanoate (D35) (551 mg) was added. The reaction mixture was stirred at 60° C. for 2 h, and then TBAF (2092 mg) was added. The reaction vessel was sealed and heated in Biotage Initiator using initial normal to 130° C. for 3 h. After cooling the reaction, the solvent was removed. Water (90 mL) and ethanol (30 mL) was added to the residue, a yellow solid was formed, filtered and dried in vacuo to afford the product ethyl 3-(7-{5-[3,4-bis(ethyloxy)phenyl]-1,2,4-oxadiazol-3-yl}-1H-indol-3-yl)propanoate (D66) (706 mg). δH (CDCl3, 400 MHz): 1.26 (3H, t), 1.52-1.57 (6H, m), 2.76 (2H, t), 3.18 (2H, t), 4.16 (2H, q), 4.19-4.28 (4H, m), 7.02 (1H, d), 7.20 (1H, d), 7.28 (1H, t), 7.74 (1H, d), 7.81 (1H, d), 7.86 (1H, dd), 8.14 (1H, dd), 9.64 (1H, s). MS (ES): C25H27N3O5 requires 449. found 450.2 (M+H+).

1. stirringThe reaction mixture was stirred at 60° C. for 2 h
2. customThe reaction vessel was sealed
3. temperatureheated in Biotage Initiator
4. customnormal to 130° C.
5. customfor 3 h
6. temperatureAfter cooling
7. customthe reaction
8. customthe solvent was removed
9. additionWater (90 mL) and ethanol (30 mL) was added to the residue
10. customa yellow solid was formed
11. filtrationfiltered
12. customdried in vacuo