Methyl N-(triethylammoniosulfonyl)carbamate → HCID 59608329, compound

Participants

Reaction Steps

To a solution of (2R,4S)-5-biphenyl-4-yl-2-methyl-4-{2-oxo-2-[N′-(2,2,2-trifluoro-acetyl)-hydrazino]-acetylamino}-pentanoic acid benzyl ester (177 mg, 0.319 mmol) in THF (10 mL) at room temperature is added Burgess reagent (304 mg, 1.274 mmol). The reaction is carried out in a microwave at 130° C. for 30 minutes. The reaction is quenched by brine and is extracted with ethyl acetate. The combined organic layer is concentrated and purified by reverse phase HPLC [70% to 85% acetonitrile-H2O (containing 0.1% TFA)] to give the benzyl ester of the title compound. The obtained benzyl ester intermediate is dissolved in MeOH (4 mL) and is hydrogenated with 10% Pd/C at room temperature for 20 minutes. The reaction mixture is purified by reverse phase HPLC [45% to 70% acetonitrile-H2O (containing 0.1% TFA)] to give (2R,4S)-5-biphenyl-4-yl-2-methyl-4-[(5-trifluoromethyl-[1,3,4]oxadiazole-2-carbonyl)-amino]-pentanoic acid. HPLC Retention time 1.38 minutes (condition D); MS 448 (M+1); 1H NMR (400 MHz, DMSO-d6) δ ppm 1.09 (d, J=7.3 Hz, 3H), 1.60-1.71 (m, 1H), 1.84-1.95 (m, 1H), 2.41-2.49 (m, 1H), 2.80-2.88 (m, J=13.9, 6.1 Hz, 1H), 2.92 (dd, J=13.6, 7.8 Hz, 1H), 4.21-4.34 (m, 1H), 7.27-7.37 (m, 3H), 7.44 (t, J=7.7 Hz, 2H), 7.58 (d, J=8.3 Hz, 2H), 7.61-7.66 (m, 2H), 9.50 (d, J=8.8 Hz, 1H), 12.05 (br. s., 1H).

Provenance & Evidence