Citric Acid → HCID 69799811, compound

Participants

Reaction Steps

With continued reference to Scheme K, To Compound XXVII: 5-(2-(N,N′-Bis-(BOC)-guanidino)-ethylcarbamoyl)-thiophene-2-carboxylic acid methyl ester (2.2 g, 4.66 mmol) in 50% THF/H2O (50 ml) was added 1.5 eq. of LiOH (294 mg, 6.99 mmol) and the reaction mixture was left to stir at room temperature for 3 hours. 10% citric acid solution was added until acidic pH and THF was evaporated. The aqueous solution was then extracted with CH2Cl2 (3×70 ml). The organic phases were combined and washed with a solution of Brine, dried over MgSO4 and evaporated to give the desired product in 84% yield. 1H NMR (CD3OD, 400 MHz) δ 1.34-1.66 (m, 21H), 3.49-3.67 (m, 4H), 7.61-7.70 (dd, 2H).

Provenance & Evidence