N-bromobutanimide → HCID 77230682, compound

1-(2,1,3-Benzoxadiazol-5-yl)ethanone (230 mg, 1.42 mmol) was combined with NBS (265 mg, 1.49 mmol) and ammonium acetate (11 mg, 0.14 mmol) in ether (5 mL) and the resulting mixture was stirred at RT for 1 h. Carbon tetrachloride was added (5 mL) and the mixture was heated at 80° C. for 1 h. An additional 0.2 equivalents of NMS were added and the mixture was heated at 80° C. for an additional 2 h. The reaction mixture was filtered and the filtrate was washed with water and the organic layer was dried over MgSO4. The crude product which still contained starting material was used without purification in the next step. Step D: 1-(2,1,3-benzoxadiazol-5-yl)-2-(4-{[4-(1H-tetrazol-1-yl)phenyl]acetyl}piperazin-1-yl)ethanone-1-(2,1,3-Benzoxadiazol-5-yl)-2-bromoethanone (crude, 200 mg, 0.830 mmol) was combined with 1-(piperazin-1-yl)-2-[4-(1H-tetrazol-1-yl)phenyl]ethanone hydrochloride (256 mg, 0.830 mmol) in acetonitrile (2 mL) and treated with Hunig's base (0.145 mL, 0.830 mmol). The reaction mixture was stirred at 60° C. for 5 h. The reaction mixture was concentrated and purification by preparative TLC afforded the title compound. LC/MS: [(M+1)]+=433.

1. temperaturethe mixture was heated at 80° C. for 1 h
2. additionAn additional 0.2 equivalents of NMS were added
3. temperaturethe mixture was heated at 80° C. for an additional 2 h
4. filtrationThe reaction mixture was filtered
5. washthe filtrate was washed with water
6. dry with materialthe organic layer was dried over MgSO4
7. customwas used without purification in the next step
8. stirringThe reaction mixture was stirred at 60° C. for 5 h
9. concentrationThe reaction mixture was concentrated
10. custompurification by preparative TLC

ORD record

ord-9fcac4c5409546db9dc72f874a8bf891

Source dataset

uspto-grants-2015_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09056859B2