HCID 20770837, compound → HCID 20770846, compound

Participants

Reaction Steps

Compound 72D (4.04 g, 13.8 mmol) was dissolved in 200 ml methanol. Nitrogen was bubbled for 5 minutes followed by the addition of a 2N NaOH solution (1.4 g/17 ml water). The solution was heated at reflux and tuned brown after 10 minutes. The reaction was concentrated to ca. 50 ml under vacuum and acidified to pH<4 with 2N HCl. The product was extracted into ethyl acetate 2×100 ml, dried over anhydrous sodium sulfate, decanted and concentrated. The crude acid was dissolved into 100 ml anhydrous methanol followed by 5 drops concentrated sulfuric acid. This was heated at reflux for 3 h then cooled to room temp. 500 mg dithiothreitol was added followed by 100 mg sodium borohydride. This was stirred for 1 h and concentrated to an oil. The crude thiol ester was dissolved into 100 ml dichloromethane, filtered through silica and eluted with 300 ml dichloromethane. The filtrate was concentrated and purified by liquid chromatography to give the title product as a yellow oil. MS m/z 222 (M+1).

Provenance & Evidence