29866-05-5Relevant academic research and scientific papers
Highly efficient Meerwein-Ponndorf-Verley reductions over a robust zirconium-organoboronic acid hybrid
Song, Jinliang,Hua, Manli,Huang, Xin,Visa, Aurelia,Wu, Tianbin,Fan, Honglei,Hou, Minqiang,Zhang, Zhaofu,Han, Buxing
, p. 1259 - 1265 (2021/02/26)
The Meerwein-Ponndorf-Verley (MPV) reaction is an attractive approach to selectively reduce carbonyl groups, and the design of advanced catalysts is the key for these kinds of interesting reactions. Herein, we fabricated a novel zirconium organoborate using 1,4-benzenediboronic acid (BDB) as the precursor for MPV reduction. The prepared Zr-BDB had excellent catalytic performance for the MPV reduction of various biomass-derived carbonyl compounds (i.e., levulinate esters, aldehydes and ketones). More importantly, the number of borate groups on the ligands significantly affected the catalytic activity of the Zr-organic ligand hybrids, owing to the activation role of borate groups on hydroxyl groups in the hydrogen source. Detailed investigations revealed that the excellent performance of Zr-BDB was contributed by the synergetic effect of Zr4+and borate. Notably, this is the first work to enhance the activity of Zr-based catalysts in MPV reactions using borate groups.
Regioselectivity of Cobalamin-Dependent Methyltransferase Can Be Tuned by Reaction Conditions and Substrate
Pompei, Simona,Grimm, Christopher,Farnberger, Judith E.,Schober, Lukas,Kroutil, Wolfgang
, p. 5977 - 5983 (2020/10/06)
Regioselective reactions represent a significant challenge for organic chemistry. Here the regioselective methylation of a single hydroxy group of 4-substituted catechols was investigated employing the cobalamin-dependent methyltransferase from Desulfitobacterium hafniense. Catechols substituted in position four were methylated either in meta- or para-position to the substituent depending whether the substituent was polar or apolar. While the biocatalytic cobalamin dependent methylation was meta-selective with 4-substituted catechols bearing hydrophilic groups, it was para-selective for hydrophobic substituents. Furthermore, the presence of water miscible co-solvents had a clear improving influence, whereby THF turned out to enable the formation of a single regioisomer in selected cases. Finally, it was found that also the pH led to an enhancement of regioselectivity for the cases investigated.
SUBSTITUTED NAPHTHYRIDINONE COMPOUNDS USEFUL AS T CELL ACTIVATORS
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Page/Page column 833, (2020/01/24)
Disclosed are compounds of Formula (I) or a salt thereof, wherein: R1, R2, R3, R4, R5, and m are defined herein. Also disclosed are methods of using such compounds to inhibit the activity of one or both of diacylglycerol kinase alpha (DGKα) and diacylglycerol kinase zeta (DGKζ), and pharmaceutical compositions comprising such compounds. These compounds are useful in the treatment of viral infections and proliferative disorders, such as cancer.
ECO-FRIENDLY MATERIALS AND METHODS FOR RENEWABLE AND SUSTAINABLE APPLICATIONS IN MATERIAL CHEMISTRY
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Page/Page column 42, (2017/09/27)
The invention relates to novel hydrazide-based templates, methods of making the same, and methods of using the hydrazide-based templates as molecular scaffolds for asymmetric light driven transformations, light driven material synthesis, and biological applications. Furthermore, the present invention relates to photoinitiators, monomers, and polymers derived from biomass, together with methods and methods of using the same.
Enantioselective synthesis of 1,4-dihydrobenzoxathiins via sulfoxide-directed borane reduction
Waters, Marjorie S.,Onofiok, Ekama,Tellers, David M.,Chilenski, Jennifer R.,Song, Zhiguo Jake
, p. 3389 - 3396 (2008/02/11)
A novel sulfoxide-directed borane reduction was shown to give a variety of 2-substituted 1,4-dihydrobenzoxathiins. For all substrates evaluated, the reaction is completely stereospecific. Application of this methodology to the chiral synthesis of an artif
Tobacco smoke chemistry. 2. Alkyl and alkenyl substituted guaiacols found in cigarette smoke condensate.
Arnarp,Bielawski,Dahlin,Dahlman,Enzell,Pettersson
, p. 44 - 50 (2007/10/02)
A series of alkyl and alkenyl substituted guaiacols, which comprise a group of biologically and organoleptically active compounds, have been synthesized. Mass spectra and GC retention times for these have been recorded and compared with those obtained for constituents of a weakly acidic fraction of smoke condensate derived from American blend type cigarettes. On the basis of these results, 25 guaiacols have been identified, 18 of which have not been detected in tobacco smoke condensate previously.
