The synthesis of novel polycyclic heterocyclic ring systems via photocyclization. 22 [1,2]. Dibenzo[f, h]benzothieno[2,3-c]quinoline, dibenzo[f, h]benzothieno[2,3-c] [1,2,4]triazolo[4,3-a]quinoline and dibenzo[f, h]naphtho[2',1':4,5]thieno[2,3-c]quinoline

1. Luo, J.-K.
2. Cabal, M.P.
3. Federspiel, R.F.
4. Castle, R.N.