When 5H-dibenz[b,f]azepine is dissolved in pure sulfuric acid it undergoes an oxidative dismutation into two acridine derivatives: 9-formylacridine and 9,9'-ethene-1,2-diyl-bis-acridine.DGI/MCyT of Spain (project BQU-2000-0645), European Community Marie Curie individual Fellowship (program: “Improving Human Research Potential and the Socio-economic Knowledge Base”, contract number: HMPF-CT-2001-01120), Spanish "Ministerio de Educación, Ciencia y Deportes" postdoctoral fellowship (SB2001-0174).Peer reviewed