D issolve the residue in 2 ml of the ethyl acetate/glacial acetic acid/acetone mixture (3.9) by re-heating at 50 şC, leave to cool, add 10 ml of the dichloromethane/glacial acetic acid mixture (3.10) and mix.
Ob gretju na 50 °C se ostanek raztopi v 2 ml mešanice dietiletra, ledoceta in acetona (3,9), pusti, da se ohladi, doda 10 ml mešanice diklorometana in ledoceta (3.19) ter premeša.