2-Aminothiazole → (E)-4-cyclopentyl-2-[4-(5-methyl-tetrazol-1-yl)-3-trifluoromethyl-phenyl]-but-2-enoic acid thiazol-2-ylamide

Temperature

0 °C

A solution of triphenylphosphine (450 mg, 1.72 mmol) in methylene chloride (20 mL) was cooled to 0° C. and then treated with N-bromosuccinimide (306 mg, 1.72 mmol). The reaction mixture was stirred at 0° C. for 30 min and then treated with a solution of the (E)-4-cyclopentyl-2-[4-(5-methyl-tetrazol-1-yl)-3-trifluoromethyl-phenyl]-but-2-enoic acid (326 mg, 0.86 mmol) in methylene chloride (5 mL). The reaction mixture was stirred for 15 min at 0° C. and then allowed to warm to 25° C. where it was stirred for 1.5 h. The reaction mixture was then treated with 2-aminothiazole (257 mg, 2.57 mmol), and the resulting suspension was stirred for 2 d at 25° C. The reaction mixture was then concentrated in vacuo to remove methylene chloride, and the residue was diluted with ethyl acetate (20 mL) and water (30 mL). The two layers were separated, and the aqueous layer was extracted with ethyl acetate (1×15 mL). The combined organic extracts were successively washed with a saturated aqueous sodium bicarbonate solution (1×50 mL) and a saturated aqueous sodium chloride solution (1×50 mL), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 3/1 hexanes/ethyl acetate) afforded (E)-4-cyclopentyl-2-[4-(5-methyl-tetrazol-1-yl)-3-trifluoromethyl-phenyl]-but-2-enoic acid thiazol-2-ylamide (52 mg, 13%) as an amorphous white solid: EI-HRMS m/e calcd for C21H21F3N6OS (M+) 462.1450, found 462.1451.

1. stirringThe reaction mixture was stirred for 15 min at 0° C.
2. temperatureto warm to 25° C. where it
3. stirringwas stirred for 1.5 h
4. stirringthe resulting suspension was stirred for 2 d at 25° C
5. concentrationThe reaction mixture was then concentrated in vacuo
6. customto remove methylene chloride
7. additionthe residue was diluted with ethyl acetate (20 mL) and water (30 mL)
8. customThe two layers were separated
9. extractionthe aqueous layer was extracted with ethyl acetate (1×15 mL)
10. washThe combined organic extracts were successively washed with a saturated aqueous sodium bicarbonate solution (1×50 mL)
11. dry with materiala saturated aqueous sodium chloride solution (1×50 mL), dried over anhydrous magnesium sulfate
12. filtrationfiltered
13. concentrationconcentrated in vacuo

ORD record

ord-81f746d8063c44888e4278720adc8093

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06369232B1