Purify PUGNAC by flash chromatography (silica gel and elute with EtOAc/hexane 3:2), evaporate, and the foam is recrystallised from EtOAc/MeOH. The purity is checked by TLC on Merck SiO2 gel 60 F254 and the spots are detected by spraying with 0.025M I2 in 10% aqueous H2SO4 and heating at 200o. It has RF 0.21. The acetate is hydrolysed with NH3/MeOH. [Helv Chim Acta 68 2254 1985, Helv Chim Acta 73 1918 1990.] Acetobromo-
