Pyridine → HCID 10097050, compound

Participants

Reaction Steps

1-Benzyl-6-(4-fluoro-benzyl)-4,8-dihydroxy-1H-1,3,6-triaza-s-indacene-5,7-dione 255 (1 g, 2.39 mmol, 1 equiv.) was dissolved in a flask containing DMF (24 mL, 0.1 M) and pyridine (290 μL, 2.88 mmol, 1.5 equiv.). Ethyl chloroformate was added (231 μL, 2.88 mmol, 1.2 equiv.) under a nitrogen atmosphere. The reaction was stirred for 16 hours before being quenched with saturated NH4Cl (30 mL) and extracted with ethyl acetate (2×30 mL) and the organic layer washed several times with water (4×30 mL), saturated NaHCO3 (50 mL), brine solution (50 mL). It was dried over Na2SO4, filtered and concentrated in vacuo. Trituration was carried out with Hexanes/Ethyl acetate (1/4, 100 mL) to remove the corresponding biscarbonate to give carbonic acid 3-benzyl-6-(4-fluoro-benzyl)-8-hydroxy-5,7-dioxo-3,5,6,7-tetrahydro-1,3,6-triaza-s-indacen-4-yl ester ethyl ester 256 (13%, 145 mg, 0.296 mmol). 1H NMR (300 MHz) DMSO d6 δ 8.63 (s, 1 H), 7.45-7.35 (m, 6 H), 7.15-7.33 (m, 4 H), 5.59 (s, 2 H), 4.63 (s, 2 H), 3.98 (q, J=6.9 Hz, 2 H), 1.17 (t, J=6.9 Hz, 3 H). MS: 490.2 (M+1). TLC Rf: 0.6 Ethyl acetate.

Provenance & Evidence