abstract |
Rhizoxin and rhizoxin-2-ene derivatives of formula (I):n [in which: n is 1 to 25; A is an extra bond or oxygen, X is oxygen, sulphur, nitrogen or carbonyl; and R is hydrogen, carboxylic acyl having from 1 to 25 carbon atoms, alkoxycarbonyl group having from 2 to 26 carbon atoms, phosphono, alkylphosphono group in which the alkyl part has from 1 to 25 carbon atoms, dialkylphosphono group in which each alkyl part has from 1 to 25 carbon atoms, alkyl group having from 1 to 25 carbon atoms, aralkyl, cycloalkyl, heterocyclic, alkylthio group in which the alkyl part has from 1 to 25 carbon atoms, aralkylthio, or heterocyclylthio, or when X represents a nitrogen atom, R is R¹ and R², where R¹ and R² are hydrogen, alkyl, acyl, alkoxycarbonyl, phosphono, alkylphosphono or dialkylphosphono] have valuable anti-tumour activity. They may be prepared by acylation of rhizoxin or rhizoxin-2-ene. |