I. Cardinaud et al., SYNTHESIS OF PYRROLOQUINOLINE AND PYRROLONAPHTHYRIDINE BY AN INTRAMOLECULAR CYCLIZATION REACTION, Heterocycles, 36(11), 1993, pp. 2513-2522
4-methylthiopyrrolo[1,2-a][1,8]naphthyridine and pyrrolo[1,2-a]quinoli
ne were prepared by an intramolecular cyclisation in acidic media of l
sulfinyl-1-methylthio-2-[3-(2-(1-pyrrolyl)pyridin or phenyl)]ethylene.