Selenium-containing heterocycles 3*. synthesis and reactions of selenolo- [2,3-b]pyridine derivatives and related fused tricyclic systems

Abstract

Selenium has long been recognized as a dietary antioxidant and is now known to be an essential component of the active sites of several enzymes, including glutathione peroxidase [2] and thioredoxin reductase, which catalyze reactions essential for the protection of cellular components against oxidative and radical damage [3]. Moreover, previous work in our laboratory describes the synthesis of pyrimidoselenolo-[2,3-b]quinoline [4] and pyrimidoselenolo[2,3-c]pyridazine derivatives [5] and indicates that certain compounds possess significant anti-inflammatory and analgesic activities with strong fungicidal effects. Furthermore, in Part 1 [6] [3',2':4,5]pyrimido[1,6-a]pyrimidine derivatives. Prompted by these observations and in continuation of our work we report herein new classes of fused tri-and tetracyclic systems containing the selenolo[2,3-b]pyridine fragment in the hope that members of these series may find interesting biological applications.

Synthetic Approaches to Organoselenium Derivatives with Antimicrobial and Anti-Biofilm Activity

“…Abdel-Hafez and co-workers synthesized a series of seleno[2,3-b]pyridine derivatives starting from 4-chloro-2,7,9trimethylpyrido[3',2':4,5]seleno[2,3-b]pyrimidine 56 to obtain a new class of fused tri-and tetracyclic systems through nucleophilic substitution reaction with ethanolamine, morpholine and thiourea, as showed in Scheme 11 [24].…”