Antitumor compositions and methods of treatment

A compound useful in the treatment of susceptible neoplasms in mammals having the formula ##STR7## wherein X.sup.1 is halo;

• X.sup.2 is hydrogen, halo, or CF.sub.3 ;
• and
• wherein
• B is:
• a) C.sub.2 -C.sub.7 alkyl with the proviso that when B is n-butyl X.sup.2 is other than hydrogen;
• e) a C.sub.5 -C.sub.6 cycloalkyl;
• or
• f) RZR.sup.1 -where R is phenyl or C.sub.1 -C.sub.2 alkyl, R.sup.1 is CH.sub.2 or C.sub.2 H.sub.4, and Z is oxygen or sulfur;
• or pharmaceutically acceptable salts thereof.