38066-16-9Relevant articles and documents
Dipolar vinyl sulfur fluorescent dyes. Synthesis and photophysics of sulfide, sulfoxide and sulfone based D-π-A compounds
Mon?alves, Matias,Zanotto, Gabriel M.,Toldo, Josene M.,Rampon, Daniel S.,Schneider, Paulo H.,Gon?alves, Paulo F. B.,Rodembusch, Fabiano S.,Silveira, Claudio C.
, p. 8832 - 8842 (2017)
New vinyl sulfides and sulfoxides were obtained in good yields using the Horner-Wadsworth-Emmons (HWE) reaction. The vinyl sulfides and sulfoxides presented preferentially the E-stereochemistry. The respective vinyl sulfones were obtained in good yields from the vinyl sulfides by a simple oxidation step using mCPBA, solely as the E isomers. These derivatives presented absorption maxima in the UV-A region with molar absorptivity coefficients and radiative rate constant values ascribed to spin and symmetry-allowed 1π-π* electronic transitions. Experimentally, a small solvatochromic effect indicated an almost absent charge transfer character in the ground-state. A fluorescence emission in the violet-green region with a significative redshift on the maxima with increasing solvent polarity was observed, which could be related to a better electron delocalization in the excited state, as a result of an intramolecular charge transfer state. DFT and TD-DFT calculations were performed at the PBE1PBE and CAM-B3LYP levels of theory. No solvatochromic effect was observed in the ground state, but a bathochromic effect was detected in the emission maxima. Starting from sulfides to sulfones, the addition of oxygen atoms improved the charge separation, enabling an ICT state, mainly in P3 and P5. This charge separation was more efficient in the triphenylamino derivatives than among the pyrene derivatives since the first one has a better electron-donating character.
Synthesis of gem-Dimethylcyclopentane-Fused Arenes with Various Topologies via TBD-Mediated Dehydro-Diels-Alder Reaction
Zhang, Liyan,Jin, Tengda,Guo, Yingjie,Martin,Sun, Keju,Dudley, Gregory B.,Yang, Jingyue
, p. 16716 - 16724 (2021/11/16)
The development of efficient methods for the synthesis of substituted polycyclic arenes with various topologies is in high demand due to their excellent electrical and optical properties. In this work, a series of gem-dimethylcyclopentane-fused arenes with more than ten topologies were synthesized via a 1,5,7-Triazabicyclo[4.4.0]dec-5-ene (TBD)-mediated dehydro-Diels-Alder reaction with moderate to good yields. The introduction of the near-planar gem-dimethylcyclopentane moiety not only impacts the molecular conjugative system but also regulates the intermolecular π-πinteractions and crystal packing, which are critical for the photoelectric performance of arenes. The photophysical properties, molecular geometry, molecular packing of these compounds, and electrochemical properties were investigated by UV-vis absorption, fluorescence emission spectra, DFT calculations, single-crystal X-ray structure analysis, and cyclic voltammetry study.
Generation of potent Nrf2 activators via tuning the electrophilicity and steric hindrance of vinyl sulfones for neuroprotection
Song, Zi-Long,Hou, Yanan,Bai, Feifei,Fang, Jianguo
, (2020/12/21)
Oxidative stress is constantly involved in the etiopathogenesis of an ever-widening range of neurodegenerative diseases. As a consequence, effective repression of cellular oxidative stress to a redox homeostatic condition is a promising and feasible strategy to treat, or at least retard the progression of, such disorders. Nrf2, a primary orchestrator of cellular antioxidant response machine, is responsible for detoxifying and compensating for deleterious oxidative stress via transcriptional activation of a diverse array of antioxidant biomolecules. In the framework of our persistent interest in disclosing small molecules that interfere with cellular redox-regulating machinery, we report herein the synthesis, optimization, and biological assessment of 47 vinyl sulfone scaffold-bearing small molecules, most of which exhibit robust neuroprotective effect against H2O2-mediated lesions to PC12 cells. After initial screening, the most potent neuroprotective compounds 9b and 9c with marginal cytotoxicity were selected for the follow-up studies. Our results demonstrate that their neuroprotective effects are attributed to the up-regulation of a panel of antioxidant genes and corresponding gene products. Further mechanistic studies indicate that Nrf2 is indispensable for the cellular performances of 9b and 9c, arising from the fact that silence of Nrf2 gene drastically nullifies their protective action. Taken together, 9b and 9c discovered in this work merit further development as neuroprotective candidates for the treatment of oxidative stress-mediated pathological conditions.
