Synthesis of Functionalized Organoselenium Materials: Selenides and Diselenides Containing Cholesterol

Abstract

A simple and efficient procedure for the synthesis of three new series of chalcogen liquid crystals, based on selenides and diselenides, containing cholesterol in their structure, is described. Thermal and liquid crystalline properties were investigated by POM, DSC, TGA and XRD scattering. Six of the nine molecules synthesized showed liquid crystal properties, with smectic mesomorphism. All the compounds presented good thermal stability. The smectic mesomorphism was confirmed through XRD analysis. The morphology of the surface of the films was investigated by using atomic force microscopy (AFM). All prepared diselenides showed good glutathione peroxidase like activity and one of the diselenides was 3.3 times more active than the standard Ebselen.

Radical-Mediated Reactions of α-Bromo Aluminium Thioacetals, α-Bromothioesters, and Xanthates for Thiolactone Synthesis

“…In an effort to ascertain the mechanism by which alcohol 7 was formed, α-phenylselanyl carboxylic 8 was prepared from diphenyl diselenide in two steps according to a modified literature procedure [ 21 ]. The carboxylic acid was subsequently coupled with the allyl thiol 5 in good yield to give thioester 9 ( Scheme 2 B).…”

Cholesterol-Based Compounds: Recent Advances in Synthesis and Applications

“…In 2015, Frizon and coworkers described the synthesis of and preliminary studies on the thermal and photophysical properties of selenium liquid crystals containing cholesterols 247 , 249 , 251 , and 253 . The synthesis of three new series of selenide 247 / 251 and diselenide compounds 249 / 253 was accomplished via esterification of cholesterol 28 with the appropriate selenide 246 / 250 or diselenide acid 248 / 252 (Scheme 61) [63].…”

Synthesis of 2,1,3-Benzoxadiazole Derivatives as New Fluorophores—Combined Experimental, Optical, Electro, and Theoretical Study

“…As part of our continued involvement in the chemistry of Nheterocycles (Saba et al, 2015(Saba et al, , 2016(Saba et al, , 2017(Saba et al, , 2018(Saba et al, , 2020Rafique et al, 2016Rafique et al, , 2018aSilva et al, 2017;Bettanin et al, 2018;Peterle et al, 2018;Rodigues et al, 2018;Tornquist et al, 2018;Meirinho et al, 2019;Neto et al, 2020;Scheide et al, 2020) and material sciences (Frizon et al, 2014(Frizon et al, , 2015(Frizon et al, , 2016(Frizon et al, , 2018Bo et al, 2016Bo et al, , 2018Westrup et al, 2016;Matzkeit et al, 2018;Regis et al, 2018), herein, we report the synthesis and characterization of BOX derivatives containing electrondonor groups (alkylated tetrazole rings) connected to the 2,1,3-BOX group as an electron-acceptor unit. In addition, thermal, electrochemical, and theoretical predictions were made and photophysical analysis was performed to study the stability, likely geometry, and luminescence properties of these compounds in their ground and excited electronic states.…”