Abstract: Novel methods for treatment of neoplastic disease states in animals, which methods comprise administering a therapeutically effective amount of a compound of the formula V, ##STR1## wherein: Y is hydrogen of lower alkyl; and X is a radical of the formula --O--R, wherein R is:N,N-di (hydroxy lower alkyl)amino lower alkyl, or tri-lower alkoxy silyl lower alkyl, or cyclo lower alkyl, or halo substituted lower alkoxy lower alkyl, or tetrahydro pyranyl, or carboethoxy lower alkyl, or 1-lower alkyl pyrrolidinyl lower alkyl, or N-pyrrolidinyl lower alkyl, or 1-lower alkyl pyrrolydinyl, or dioxanyl, or hydroxy lower alkenyl, or hydroxy lower alkyl thio lower alkyl thio lower alkyl, or dioxanyl lower alkyl, or lower alkyl thio lower alkyl, or phenyl thio lower alkyl, or phenoxy lower alkyl, or thiophenyl lower alkyl, or 1-lower alkyl piperidyl, or alkyl carbonyl amino alkyl, or N-piperidyl lower alkyl, or lower alkoxy lower alkyl or lower alkyl thio hydroxy lower alkyl, or 1-lower alkyl N-piperazinyl lower alkyl, or N