Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Multifunctional Antioxidants: Regenerable Radical‐Trapping and Hydroperoxide‐Decomposing Ebselenols

“…[17] Previously,w ef ound that suitably positioned chalcogen substituents (alkylseleno [18] and alkyltelluro [19] groups) in phenols could increase the rate constant for quenching of peroxyl radicals by up to four orders of magnitude.W e therefore thought it would be interesting to install hydroxy groups into one or the other of the aromatic rings in ebselen. [12] Ebselenols 4-7 were obtained in 70-75 %yields by O-demethylation induced by boron tribromide.A ddition of as toichiometric quantity of BBr 3 was crucial. [14b] Methyl-protected isoselenazolones were prepared as shown in Scheme 1f rom the corresponding 2-halobenzamides and selenium by means of copper catalysis.…”

“…[10,11] Av ariety of derivatives of the selenacycle have been prepared [12][13][14] and evaluated for their capacity to mimic the natural enzymes. [10,11] Av ariety of derivatives of the selenacycle have been prepared [12][13][14] and evaluated for their capacity to mimic the natural enzymes.…”

Thermal and Photoinduced Copper-Promoted C–Se Bond Formation: Synthesis of 2-Alkyl-1,2-benzisoselenazol-3(2H)-ones and Evaluation against Mycobacterium tuberculosis

“…36,37 We noted that diaryl selenides have been successfully synthesized using phen-CuI in combination with KSeCN. 48 On the basis of this observation, we surmised that the substitution of insoluble selenium power with KSeCN would produce an intermediate selenocyanate 6 that would cyclize to a selenazol-3(2 H )-one under base-promoted conditions.…”

Multifunctional Antioxidants: Regenerable Radical‐Trapping and Hydroperoxide‐Decomposing Ebselenols

“…Theo rganoselenium compound ebselen, specifically 2phenyl-1,2-benzisoselenazol-3(2H)-one (3;F igure 1), has been known for more than thirty years to mimic the action of the GPx enzymes. [10,11] Av ariety of derivatives of the selenacycle have been prepared [12][13][14] and evaluated for their capacity to mimic the natural enzymes. [15,16] Them any interesting biological activities of the ebselen family of compounds,b oth in vitro and in vivo,h ave also stimulated the search for other small-molecule organoselenium compounds with acapacity to mimic the GPx enzymes.…”

“…[14b] Methyl-protected isoselenazolones were prepared as shown in Scheme 1f rom the corresponding 2-halobenzamides and selenium by means of copper catalysis. [12] Ebselenols 4-7 were obtained in 70-75 %yields by O-demethylation induced by boron tribromide.A ddition of as toichiometric quantity of BBr 3 was crucial. An excess amount of BBr 3 caused cleavage of the SeÀNb ond and substoichiometric amounts led to incomplete O-demethylation.…”