Chloromethyl formate → (S)-3-[3-(9-methylthio-6-oxo-2,3,3a,4-tetrahydro-1H,6H-5,8,10,10b-tetraazabenzo[e]azulen-5-yl)phenyl]-1,2,4-oxadiazol-5(4H)-one

Participants

Reaction Conditions

Reaction Steps

(S)—N′-hydroxy-3-(9-methylthio-6-oxo-2,3,3a,4-tetrahydro-1H,6H-5,8,10,10b-tetraazabenzo[e]azulen-5-yl)benzamidine (200 mg, 0.52 mmol) obtained in Step 1 of Example 75 was dissolved in pyridine (3.0 mL), and the mixture was stirred at 90° C. for 4 hours after adding chloromethyl formate (0.12 mL, 1.56 mmol) under ice-cooled conditions. The mixture was diluted with chloroform, washed with water and saturated brine, and the organic layer was dried over anhydrous magnesium sulfate. The residue obtained by concentrating the mixture under reduced pressure was then purified by silica gel column chromatography to give (S)-3-[3-(9-methylthio-6-oxo-2,3,3a,4-tetrahydro-1H,6H-5,8,10,10b-tetraazabenzo[e]azulen-5-yl)phenyl]-1,2,4-oxadiazol-5(4H)-one (236 mg, quantitative).

Provenance & Evidence