: Selenium promoted-cyclization of unsaturated substrates containing internal nitrogen nucleophiles, such as different amines and amides, including the examples of its application in the synthesis of more complex polycyclic compounds is reviewed. Selenocyclization reactions of some more specific polyfunctional substrates, like Biginelli hybrids and hydantoins, are also covered.

The 3-arylidene-2-thiohydantoin derivative, 3-[(2-hydroxybenzylidene) amino]-2-thioxoimidazolidin-4-one, was synthesized in a two-step condensation reaction of 2-hydroxybenzaldehyde, thiosemicarbazide and ethyl chloroacetate. The ligand was structurally characterized by NMR and IR spectroscopy, as well as by elemental analysis. In the reaction of the well-known polymeric trans-[CuCl2(DMSO)2]n complex with the polydentate thiohydantoin type ligand, instead of the corresponding copper thiohydantoin complex, unexpectedly, the dinuclear cis-[{CuCl(DMSO)2}(?-Cl)]2 complex (1) was formed predominantly as the final stable product. The structure of the complex 1 was confirmed by single crystal X-ray diffraction analysis. The cis-complex is obtained through assisted isomerization of the trans-form, in which the thiohydantoin derivative has a crucial role.

5-Alkenyl hydantoins and alkenyl spirohydantoins are converted into bicyclic and tricyclic hydantoins, under indirect electrochemical conditions, generating the phenylselenyl cation in situ. The reactions proceeded in good to exelent yields. The influence of electrochemical conditions on regio- and diastereoselectivity of the selenocyclization reactions is investigated.

The knowledge of the essential role of copper in the human body, especially in its involvement in various important metalloenzymes, such as cytochrome c oxidase, copper-zinc superoxide dismutase, tyrosinase, lysyl oxidase and other, has greatly stimulated research interest in copper coordination compounds from both chemical and medicinal perspectives. Dinuclear copper complexes, in particular, have shown considerable therapeutic potential, as the unique combination of copper chemistry and dinuclear structural modifications has given rise to various highly bioactive compounds and new medicinal possibilities. In this paper, biological activities of medicinally attractive homodinuclear and heterodinuclear copper complexes are reviewed and their therapeutic potential and future perspectives are discussed. An in-depth analysis of key elements that impact their structure-activity relationships was performed and through a rational design approach, supported by the available literature, concluding remarks were given, that could possibly lead to more optimal therapeutic dinuclear copper complex structures. Known limitations regarding copper toxicity, bioavailability, metabolism and clearance were analyzed and possible strategies to mitigate them were discussed as well, including the possibe use of dinuclear copper complexes in targeted therapy and stimuli-responsive drug delivery systems. Finally, the prospects of using dinuclear copper complexes in personalized or combination therapy are postulated.

Several 2-thiohyd?nt?in?Shiff base derivatives were prepared as ecofriendly corrosion inhibitors for mild steel in acid environment. Their anticorrosion properties were studied on mild steel in 0.5 M HCl solution as corrosion electrolyte by using usu?l gr?vim?tri? and different el??tr??hemic?l techniques (w?ight l?ss m??sur?m?nt, p?t?nti?dyn?mi? p?l?riz?ti?n and p?t?nti?st?ti? ?l??tr??h?mic?l imp?d?n?? s???tr?sc???). Mild steel surface was characterized using two analytical techniques, scanning electron microscopy for surface morphology and elemental composition and atomic force microscopy. The study has shown that the inhibiting action of these environmentally benign inhibitors synthesized from inexpensive commercially available starting materials could be attributed to adsorption on the metal surface.