Synthesis of benzo-benzothiopyranoquinolines (pyridobenzothioxanthones) as possible schistosomicidal and antitumor agents.

The synthesis of a new class of compounds structurally related to cyclohexenothiaxanthones and benzothiaxanthones including a pyridine ring is described in an attempt to find compounds that may have schistosomicidal and carcinostatic activity. Synthesis was achieved through the condensation of amino-cyclohexenothiaxanthones and amino-benzothiaxanthones with ethyl acetoacetate by the Knorr and Conrad-Limpach methods.