Reactions of Lucigenin in protic solvents in the presence of amines

Abstract

Lucigenin (N,N′‐dimethyl‐9,9′‐biacridinium nitrate) 1 on heating under reflux in protic solvents in the presence of amines gives rise to the N,N′‐dimethyl‐9,9′‐biacridylidene 2 (DBA) or protected hemiaminal N‐methoxymethyl‐9,9′‐bi‐acridylidene 3. On the other hand acid hydrolysis and synchronous oxidation of hemiaminal 3 followed by reaction of monomethyl‐biacridinium nitrate 4 with sodium hydroxide in methanol or water leads to biacridine 5 (overall yield ca. 33%).

Assessment of DNA Topoisomerase I Unwinding Activity, Radical Scavenging Capacity, and Inhibition of Breast Cancer Cell Viability of N-alkyl-acridones and N,N′-dialkyl-9,9′-biacridylidenes

“…In the present work, we examined the topoisomerase I, DNA binding, cytotoxic effects, as well as the radical trapping antioxidant activity of a series of N -alkyl-acridones and N , N′ -dialkyl-9,9′-biacridylidenes with short and long alkyl chains substitution (Figure 1). N , N′ -dialkyl-biacridylidenes 7 – 12 were synthesized from the corresponding N -alkylacridones 1 – 6 by reductive coupling with zinc powder in dry ethanolic hydrogen chloride solution or from lucigenin in alkaline methanolic solution (derivative 8 ), while N -alkylacridones 1 – 6 from acridone and the corresponding alkyl bromides under phase-transfer conditions [11,12,13]. Optical and confocal microscopy imaging was assessed to clarify the role of alkyl side chain substitution in the intracellular localization of cytotoxic derivatives.…”