911371-19-2Relevant academic research and scientific papers
Synthesis of new pentacyclic diquinothiazines
Nowak, Malgorzata,Pluta, Krystian,Suwinska, Kinga,Straver, Leo
, p. 543 - 550 (2008/09/16)
(Chemical Equation Presented) Reactions of 2,2′-dichloro-3,3′- diquinolinyl sulfide 1 with ammonia derivatives and various primary alkylamines and arylamines proceeded as a thiazine ring closure to form linear annulated pentacyclic 6H-diquinothiazine 2H and 6-substituted derivatives 2 with alkyl, alkylaryl, aryl and heteroaryl substituents in moderate to good yields. Reaction with 2-chloroethylamine did not stop at the formation of half-mustard derivative 2k but ran to ethylenediquinothiazinium salt 11. 6H-Diquinothiazine 2H was N-alkylated and N-arylated to give 6-substituted derivatives 2. The crucial substrate 1 was obtained from other heteropentacenes 3 and 4 via 1,4-dithiin ring opening and further transformations. X-ray analysis of p-nitrophenyldiquinothiazine 2i revealed unexpected planar thiazine ring.
