Reivindicaciones

1. Azaanthracene-triones of the formula: <img class="EMIRef" id="418593703-ib0009" /> in which: R¹, R², R⁴ and R⁵ are the same or are different and each is a hydrogen atom or a lower alkyl group; R³ is a hydrogen atom, a lower alkyl group, a phenyl group or an amino-substituted phenyl group; and X is a -CH-, =N- or -NH-, whereby the ring containing the group X is a benzene, pyridine or dihydropyridene ring. 2. Compounds as claimed in claim 1 as specifically disclosed in any of the examples herein. 3. A pharmaceutical composition comprising a compound as claimed in claim 1 or claim 2 in association with a pharmaceutical carrier or diluent. 4. The use of a compound as claimed in claim 1 in the manufacture of an antitumoral composition.