1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride → (s)-Tert-butyl 4-(tert-butoxycarbonylamino)-5-(2-carbamoyl-1h-pyrrol-1-ylamino)-5-oxopentanoate

Participants

Reaction Steps

A mixture of 1-amino-1H-pyrrole-2-carboxamide (1.00 g, 7.99 mmol) and (5)-5-tert-butoxy-2-(tert-butoxycarbonylamino)-5-oxopentanoic acid (2.91 g, 9.59 mmol) was dissolved in THF (80 mL). To this solution was added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (1.84 g, 9.59 mmol). The reaction was stirred at rt for 1.5 h, then concentrated in vacuo. CH2Cl2 (150 mL) was added, and the reaction mixture was washed with water (2×150 mL). The organic layer was dried (MgSO4), filtered, and concentrated in vacuo. The compound was purified by silica gel flash chromatography (0-35% 90:10:1 [CH2Cl2/MeOH/conc NH4OH]/CH2Cl2) to give 10A (2.90 g, 85%). 10A had an analytical HPLC retention time=2.05 min (Waters XBridge 4.6×50 mm, 5-95% aqueous acetonitrile over 5 min containing 10 mM ammonium acetate) and a LC/MS M−−1=409.

Provenance & Evidence