σ-Complexes as biophysical and biochemical probes. Part II. Transformations of σ-complex intermediates from reaction of 4-nitrobenzofuroxan and methoxide ion

Reaction of 4-nitrobenzofuroxan with methoxide ion in methanolic dimethyl sulphoxide solution gives rise to 7-hydroxy-4-nitrobenzofurazan (as the anion) and 7-methoxy-4-nitrobenzofurazan (as the methoxide C-7 adduct); the proposed reaction mechanism invokes the formation of several transient intermediates. The results bear on the postulated mechanism for the antileukemic activity of 4-nitrobenzofuroxan.