4-Methoxycarbonylphenyl isothiocyanate → methyl 4-[(6-{[bis(3-methylbutyl)amino]carbonyl}-1-{3-[(tert-butoxycarbonyl) amino]propyl}-1H-benzimidazol-2-yl)amino]benzoate

Participants

Reaction Steps

4-methoxycarbonylphenyl isothiocyanate (327 mg, 1.5 eq) and N-methylcyclohexylcarbodiimide-N-methyl-polystyrene resin (acquired from Novabiochem; charge 1.9 mmol/g; 1.75 g, 3 eq) are added successively to a solution of tert-butyl-3-[(2-amino-5-{[bis(3-methylbutyl)amino]carbonyl}phenyl)amino]propylcarbamate (500 mg, 1 eq) in tetrahydrofuran (30 ml). The mixture is heated under reflux for 17 hours then cooled down to ambient temperature and aminomethylpolystyrene resin (acquired from Novabiochem, 2 eq) is added. After stirring for 4 hours at ambient temperature, the mixture is filtered on frit and the filtrate is concentrated under reduced pressure at 40° C. Purification of the residue by flash chromatography on silica gel (eluent: heptane/ethyl acetate 1:1) produces the expected compound in the form of a white solid (409 mg; 60% yield).

Provenance & Evidence