“…The white solid product was washed with HCl (pH 3) and water, recrystallized from ethyl acetate and hexane and dried over P 2 O 5 in vacuo. (5), N-hydroxybiuret (12), 4-(hydroxyaminocarbonyl)aminobenzoic acid (13), N-hydroxyurea (14), N,N',N''-trihydroxyisocyanuric acid (16) and N,N',N''-trihydroxibiuret (15) A mixture of 1-(N-benzyloxycarbamoyl)benzotriazole (2), N-benzyloxybiuret (6), 4-(benzyloxycabamoyl)aminobenzoic acid (7), N-benzyloxyurea (8), N,N',N''-tribenzyloxyisocyanuric acid (10) or N,N',N''-tribenzyloxybiuret (11) and 0.05 g palladium on carbon (Pd/C, 10%) in methanol (100 mL) was kept under hydrogen (r. t., normal pressure) for 1-10 hours. Pd/C was filtered off and methanol was evaporated.…”