Synthesis of Dibenzo[c,h][1,6]naphthyridine, [2]Benzopyrano[4,3-c]quinoline and Benzo[i]phenanthridine Analogues of the Quaternary Benzo[c]phenanthridines

Abstract

Three concise syntheses of the dibenzo[c,h][1,6]naphthyridines, [2]benzopyrano [4,3-c]quinolines and the benzo[i]phenanthridines are reported. All methods involve Vilsmeier chemistry, either to generate a 12-methyl-6-oxo-6H-[2]benzopyrano[4,3-c]quinolinium salt which after hydrolysis with either ammonia or methanol can ultimately be cyclised to the first two target compounds, whereas the latter can be prepared in one step from 2-(1-pyrrolidino)-3,4-dihydronaphthalene and N-methylformanilide in phosphorus oxychloride . These tetracyclic heteroaromatic ring systems are related to the benzo[c]phenanthridines, and form part of our investigations into determining the mechanism of action of this class of compounds as topoisomerase inhibitors.

Hantzsch‐like synthesis of isoquinolino[2,1‐a]quinoline‐12‐carbonitrile incorporating aryl or heteroaryl moieties at C‐13

“…To the best of our knowledge, the synthesis of monoazachrysene derivatives is uncommon in the literature, except for 2-azachrysene [47,[51][52][53][54], 5-azachrysene [51,[54][55][56][57][58], and 6-azachrysene [51,54,[59][60][61][62][63]. Although 10bazachrysenes are significantly less prevalent, Pshenichnyi et al [64], Mikhalchuk et al [65], and Gulyakevich et al [66] reported substantial advances in this field.…”

Effect of Substituents in the Syntheses of Phenyl‐Substituted Dibenzonaphthyridines

“…Particularly, some dibenzonaphthyridines, that is, quinoline dimers, act as selective 3‐phosphoinositide‐dependent kinase‐I inhibitors . Many reports represent the synthesis of functionalized naphthyridine derivatives , linear dibenzonaphthridines , and angular dibenzonaphthridines , and only very few accomplish their construction through anilinoquinolines .…”

Synthesis of linear dibenzo[1,8]naphthyridines using 2-chloro-4-methylquinolines

“…5,6 Among the quinoline derivatives, pyrido fused quinolines (benzonaphthyridines) and quinoline fused quinolines (dibenzonaphthyridines) play an important role in living cells and in pharmaceuticals. Many reports represent the synthesis of linear 7,8 and angular dibenzonaphthridines [9][10][11] and only very few accomplish their construction through anilinoquinolines. 12,13 Marine sponges are proving to be productive sources of many interesting biologically active nitrogen-containing heterocyclic compounds, including a series of 1H-benzo[de] [1,6]naphthyridine alkaloids.…”