1778-09-2Relevant articles and documents
S,S-Dialkyl Dithiocarbonates as a Convenient Source of Alkanethiolate Anions in Phase-Transfer-Catalysis Systems: An Improved Synthesis of Organic Sulfides
Degani, Iacopo,Fochi, Rita,Regondi, Valeria
, p. 630 - 632 (1983)
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Design, synthesis and biological evaluation of new imidazo[1,2-a]pyridine derivatives as selective COX-2 inhibitors
Abdel-Rahman, Hamdy M.,Ali, Mohammed R. A.,Amin, Noha H.,Elsaadi, Mohammed T.,Ismael, Ahmed S.
, (2021/10/22)
Three new series of methylsulfonyl-containing imidazo[1,2-a]pyridines 8a-d, 9a-d and 10a-d were designed and synthesized. Characterization of the chemical structure of these new compounds was performed using spectral and elemental analyses. The synthesized derivatives were tested for their ability to inhibit COX-1 and COX-2 isozymes in addition to their in vivo anti-inflammatory activity. The pyrazoline derivative 9a possessed the highest selectivity index among all compounds regarding COX-2 isozyme (SI = 39) and was almost three folds higher than celecoxib (SI = 13.76) with good in vivo anti-inflammatory activity (% edema inhibition = 11.16–32.64). Compound 10c showed the highest inhibitory activity towards COX-2 isozyme (IC50 = 1.06 μM) and it was the most potent anti-inflammatory derivative (% edema inhibition = 15.04–42.35) with ED50 value of 69.46 μmol/Kg which was approximately one and a half fold more potent than celecoxib (ED50 = 104.88 μmol/Kg). Also, the most potent anti-inflammatory compounds 9a, 9d, 10c and 10d were subjected to ulcerogenic liability and histopathological examinations. Compounds 9d and 10c showed ulcerogenic liability (% ulcerated area = 0.07 and 0.01, respectively) and histopathological changes close to celecoxib. Finally, molecular docking and computational prediction of physicochemical parameters were performed for the prepared compounds to support the biological results.
Bioinspired Radical-Mediated Transition-Metal-Free Synthesis of N-Heterocycles under Visible Light
K. Bains, Amreen,Ankit, Yadav,Adhikari, Debashis
, p. 324 - 329 (2020/11/30)
A redox-active iminoquinone motif connected with π-delocalized pyrene core has been reported that can perform efficient two-electron oxidation of a class of substrates. The design of the molecule was inspired by the organic redox cofactor topaquinone (TPQ), which executes amine oxidation in the enzyme, copper amine oxidase. Easy oxidation of both primary and secondary alcohols happened in the presence of catalytic KOtBu, which could reduce the ligand backbone to its iminosemiquinonate form under photoinduced conditions. Moreover, this easy oxidation of alcohols under aerobic condition could be elegantly extended to multi-component, one-pot coupling for the synthesis of quinoline and pyrimidine. This organocatalytic approach is very mild (70 °C, 8 h) compared to a multitude of transition-metal catalysts that have been used to prepare these heterocycles. A detailed mechanistic study proves the intermediacy of the iminosemiquinonate-type radical and a critical hydrogen atom transfer step to be involved in the dehydrogenation reaction.
Cobalt-Catalyzed Reductive C-O Bond Cleavage of Lignin β-O-4 Ketone Models via in Situ Generation of the Cobalt-Boryl Species
Gao, Kecheng,Xu, Man,Cai, Cheng,Ding, Yanghao,Chen, Jianhui,Liu, Bosheng,Xia, Yuanzhi
supporting information, p. 6055 - 6060 (2020/08/12)
An efficient and mild method for reductive C-O bond cleavage of lignin β-O-4 ketone models was developed to afford the corresponding ketones and phenols with PDI-CoCl2 as the precatalyst and diboron reagent as the reductant. The synthetic utility of the methodology was demonstrated by depolymerization of a polymeric model and gram-scale transformation. Mechanistic studies suggested that this transformation involves steps of carbonyl insertion, 1,2-Brook type rearrangement, β-oxygen elimination, and rate-limiting regeneration of the catalytic active Co-B species.
