tert-Butyl carbamate → 7-[4-(1-Amino-cyclobutyl)-phenyl]-8-phenyl-1,3-dihydro-chromeno[7,8-d]imidazole-2,6-dione

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Reaction Steps

1-[4-(7,8-Diamino-4-oxo-2-phenyl-4H-chromen-3-yl)-phenyl]-cyclobutyl}-carbamic acid tert-butyl ester: To a solution of {1-[4-(8-amino-7-nitro-4-oxo-2-phenyl-4H-chromen-3-yl)-phenyl]-cyclobutyl}-carbamic acid tert-butyl ester (420 mg, 0.8 mmol) in NMP (10 mL) and IMS (3 mL) was added 10% palladium on carbon (350 mg) under a nitrogen atmosphere. The nitrogen was evacuated and replaced with hydrogen (1 atm). The mixture was stirred at RT for 18 hours. The hydrogen atmosphere was evacuated and replaced with nitrogen and the mixture was filtered through a pad of Celite®, eluting with ethyl acetate. The solvent volume was reduced in vacuo and the resultant mixture was poured onto water and extracted with ethyl acetate (3×100 mL). The combined organic extracts were washed with brine, dried (Na2SO4), filtered, and the solvents were removed in vacuo. The resulting residue was subjected to flash chromatography (SiO2, gradient 60-70% ethyl acetate in cyclohexane) and the resulting residue triturated with water, filtered and the solid collected to give the title compound as a yellow solid (280 mg, 70%). LCMS (Method H): RT=3.66 min, [M+H]+=498.

Provenance & Evidence