Regiospecific Synthesis of Pyrido (3, 4-b)-and Pyrido (4, 3-b) carbazole-5, 11-dione Derivatives. Evaluation of Their In Vitro Antifungal or Antiprotozoological Activities.
Hetero Diels-Alder reactions between 2-or 3-bromocarbazolequinones 1a or 1b and azadiene 5 afford regiospecifically pylrido [3, 4-b]-and pyrido [4, 3-b] carbazole-3, 5, 11- triones 6a and 6b. The regiochemistry of the cycloadditions is controlled by the position of