Bis[2-(dimethylamino)ethyl] diselenide was prepared by the reaction of Na₂Se₂ with ClCH₂CH₂NMe₂. 2-(Dimethylamino)ethaneselenolate complexes of palladium(II) of the type [PdCl(SeCH₂CH₂NMe₂)]₃1, [PdCl(SeCH₂CH₂NMe₂)(PR₃)] 2, [Pd₂Cl₃(SeCH₂CH₂NMe₂)(PR₃)₂] 3 and [Pd(SeCH₂CH₂NMe₂)₂(PPh₃)₂] 4 have been synthesized and characterized by elemental analysis, IR and NMR (¹H, ³¹P, ⁷⁷Se) spectroscopy. The structures of orange 1 and of violet (λ_max = 514 nm) 2c have been established by single crystal X-ray diffraction analyses. The trimer 1 contains a six-membered Pd₃Se₃ ring in twist conformation. The thermal behaviour of three complexes, yielding Pd₁₇Se₁₅ has been investigated.

Organochalcogenido-bridged dimeric 2-methylallylpalladium complexes of the type [Pd₂(μ-ER)₂(η³-C₄H₇)₂] (1) [ER = SBu^t (1a), SPh (1b), SC₆F₅ (1c), SePh (1d), TePh (1e)] have been prepared. The structure of the SBu^t bridged complex has been established by single crystal X-ray diffraction analysis. The four-membered Pd₂S₂ ring adopts a non-planar conformation with the two η³-2-MeC₃H₄ (η³-C₄H₇) in a syn configuration. The thermal behaviour of these complexes has been investigated by thermogravimetric analysis. These complexes yield Pd₄E (E = S or Se) or Pd₃Te₂ at moderately low temperatures.

The past two decades of this century have faced half a dozen pandemics caused by different kinds of viruses, affecting millions of people globally. Among them three zoonotic viruses of the beta-coronavirus family, namely SARS-CoV-1, MERS-CoV and SARS-CoV-2, have emerged in a span of 17 years. Prevention of viral infection using vaccines is the foremost strategy to combat viral infection, but development of a vaccine for a virus remains a challenging task due to high genetic diversity and high mutation rates. Treatment of viral disease at different stages by antiviral drugs is another strategy. Several antiviral agents, primarily aiming to disrupt the viral life cycle, have been developed. Extensive research in different labs across the globe has shown that selenium deficiency has been associated with pathogenicity of several viruses like influenza viruses, HIV, HBV, HSV-1, etc. While dietary selenium supplementation has been practiced clinically, researchers are now focusing on developing new synthetic organoselenium compounds as novel antiviral agents. In this essay we have covered different classes of selenium compounds, viz. N-heterocyclic selenium derivatives, ebselen and its derivatives, organoselenium compounds, and selenium nanoparticles, which have been evaluated for effective management of viral infections.