This invention provides the compound having the structure ##STR00001## wherein n is 1-10; X is C--R.sub.11 or N, wherein R.sub.11 is H, OH, SH, F, Cl, SO.sub.2R.sub.7, NO.sub.2, trifluoromethyl, methoxy, or CO--R.sub.7, wherein R.sub.7 is alkyl, alkenyl, alkynyl, C.sub.3-C.sub.8 cycloalkyl, or aryl; Z is ##STR00002## R.sub.2 is H or NR.sub.3R.sub.4, wherein R.sub.3 and R.sub.4 are each independently H, C.sub.1-C.sub.6 alkyl, or C.sub.3-C.sub.8 cycloalkyl; R.sub.5 is OH or SH; and R.sub.6, R.sub.12, R.sub.13, and R.sub.14 are each independently H, OH, SH, F, Cl, SO.sub.2R.sub.15, NO.sub.2, trifluoromethyl, methoxy, or CO--R.sub.15 wherein R.sub.15 is alkyl, alkenyl, alkynyl, C.sub.3-C.sub.8 cycloalkyl, or aryl, or a salt of the compound,which is useful in the treatment of tumors.