Synthesis of new condensed nitrogen heterocyclic systems

• Published in: Tetrahedron Vol. 64; no. 6; pp. 1071 - 1076
• Main Authors: Korbonits, Dezső, Podányi, Benjamin, Illár, Árpád, Simon, Kálmán, Hanusz, Miklós, Hermecz, István
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 04.02.2008; Elsevier
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; ISOQUINOLINIUM CATIONS; QUINOLINIUM; ASYMMETRIC-SYNTHESIS; PSEUDOBASE FORMATION; EQUILIBRIUM
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2007.11.078

A cotarnine alkaloid-based synthesis was developed for new heptacyclic condensed diisoquinolines via the double intramolecular pseudosalt bis[1,3]dioxolo[4,5- g;4′,5′- g′][1,3,4]oxadiazolo[2,3- a;5,4- a′]diisoquinoline 6. Substitution of the central O atom in 6 by C, S, or N nucleophiles afforded the first representatives of the new ring systems bis[1,3]dioxolo[4,5- g:4,5- g′]pyrazolo[3,2- a:5,1- a′]diisoquinoline ( 7a– d), bis[1,3]dioxolo[4,5- g:4,5- g′][1,3,4]thiadiazolo[2,3- a:5,4- a′]diisoquinoline ( 8), and bis[1,3]dioxolo[4,5- g:4,5- g′][1,2,4]triazolo[3,2- a:5,1- a′]diisoquinoline ( 9a– d) under simple reaction conditions. [Display omitted] Substitution of the central O atom of the double intramolecular pseudosalt A by C, S, or N nucleophiles afforded representatives of three new heterocyclic systems B.