Abstract: The invention relates to new cytostatic compound, process for their preparation and pharmaceutical compositions containing them. More particularly, there are provided new compounds of the general formula ##STR1## in which R.sup.4 is .beta.-hydroxyl andR.sup.3 is .alpha.-ethyl; orR.sup.4 is hydrogen andR.sup.3 is .beta.-ethyl;R" is a straight chained alkyl having from 1 to 10 carbon atoms, or a branched chained alkyl having from 3 to 10 carbon atoms, in which groups the carbon atom attached to the >N.sub.a -CH.sub.2 -O-- group has a primary or secondary configuration or an alkenyl or alkinyl having from 3 to 6 carbon atoms, or an aralkyl having from 1 to 3 carbon atoms in the alkyl moiety;R.sup.1 is methoxy andR.sup.2 is acetyl,provided that if R.sup.3 is .alpha.-ethyl and R.sup.4 .beta.-hydroxyl, R.sup.4 is other than ethyl.