Diisopropylethylamine → HCID 59384387, compound

To a solution of (R)-3-(tert-butoxycarbonyl)-2,2,4-trimethyloxazolidine-4-carboxylic acid 4 (129.6 mg, 0.5 mmol) in DMF (1 mL) was added HATU (209 mg, 0.55 mol) and DIPEA (0.436 mL, 2.5 mmol). After being stirred at rt for 10 min, the reaction mixture was treated with 4-(octylthio)-3-(trifluoromethyl)benzohydrazide 3a (174 mg, 0.5 mmol) in THF (2 mL) and was left stirred overnight. Aqueous NaHCO3 solution was added and the mixture was extracted with EtOAc. The organic layer was washed with brine, dried over anhydrous Na2SO4, and evaporated under reduced pressure to give a residue, which was purified by SiO2 column chromatograph (n-hexane/EtOAc=3:7) to give (R)-tert-butyl 2,2,4-trimethyl-4-(2-(4-(octylthio)-3-(trifluoromethyl)benzoyl)hydrazinecarbonyl)oxazolidine-3-carboxylate 5a (247 mg, 84%). HPLC retention time on a C18 column (30×4.6 mm, 3.5μ) was 3.08 min with gradient 10-95% acetonitrile-H2O (0.1% TFA) in 3.5 min as mobile phase. MS (ESI, M+H+)=590.5

1. waitwas left
2. stirringstirred overnight
3. extractionthe mixture was extracted with EtOAc
4. washThe organic layer was washed with brine
5. dry with materialdried over anhydrous Na2SO4
6. customevaporated under reduced pressure
7. customto give a residue, which
8. customwas purified by SiO2 column chromatograph (n-hexane/EtOAc=3:7)

ORD record

ord-4fcc7fc2b2fc4397b9a35ce27e40cad7

Source dataset

uspto-grants-2010_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07759370B2