By condensation of 4-hydroxy-1-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid ethyl ester (I) with N-methylaniline (II) by heating at 125 C and distillation of the ethanol formed.
The oxidative cleavage of methyl beta-L-arabinopyranoside (I) with sodium periodate in water gives the dialdehyde (II), which is then cyclized with daunorubicin by means of NaHCO3 and sodium cyanoborohydride in acetonitrile/water.