138500-87-5Relevant academic research and scientific papers
Guanosine Borate Hydrogel and Self-Assembled Nanostructures Capable of Enantioselective Aldol Reaction in Water
Chen, Zhaohang,Zhou, Pengcheng,Guo, Yuanxia,Anna, None,Bai, Jiakun,Qiao, Renzhong,Li, Chao
supporting information, p. 2624 - 2631 (2022/02/16)
A guanosine-based hydrogel formed by the self-assembly of guanosine and 4-((l-prolinamide)methyl)phenylboronic acid was constructed. The G quartets were selectively stabilized by K+ ions to form a self-supporting transparent hydrogel. These guanosine-derived assemblies were used to catalyze the aldol reaction in water without any additives, affording desirable conversion and enantioselectivity of the product. The controlled assays of small-molecule components indicated that the stable assemblies were the definite species that achieved high enantioselective catalysis. The current catalytic system can be readily recovered by simple extraction and still acquired good performance of the reaction after four cycles.
Chemoselective Electrosynthesis Using Rapid Alternating Polarity
Baran, Phil S.,Carlson, Ethan,Edwards, Jacob T.,Hayashi, Kyohei,Kawamata, Yu,Saito, Masato,Shaji, Shobin,Simmons, Bryan J.,Waldmann, Dirk,Zapf, Christoph W.
supporting information, p. 16580 - 16588 (2021/10/20)
Challenges in the selective manipulation of functional groups (chemoselectivity) in organic synthesis have historically been overcome either by using reagents/catalysts that tunably interact with a substrate or through modification to shield undesired sites of reactivity (protecting groups). Although electrochemistry offers precise redox control to achieve unique chemoselectivity, this approach often becomes challenging in the presence of multiple redox-active functionalities. Historically, electrosynthesis has been performed almost solely by using direct current (DC). In contrast, applying alternating current (AC) has been known to change reaction outcomes considerably on an analytical scale but has rarely been strategically exploited for use in complex preparative organic synthesis. Here we show how a square waveform employed to deliver electric current - rapid alternating polarity (rAP) - enables control over reaction outcomes in the chemoselective reduction of carbonyl compounds, one of the most widely used reaction manifolds. The reactivity observed cannot be recapitulated using DC electrolysis or chemical reagents. The synthetic value brought by this new method for controlling chemoselectivity is vividly demonstrated in the context of classical reactivity problems such as chiral auxiliary removal and cutting-edge medicinal chemistry topics such as the synthesis of PROTACs.
Pd-Catalyzed Site-Selective Borylation of Simple Arenes via Thianthrenation?
Chen, Xiao-Yue,Huang, Yu-Hao,Zhou, Jian,Wang, Peng
, p. 1269 - 1272 (2020/08/13)
Site-selective borylation of simple arenes was realized in one pot via an electrophilic thianthrenation/Pd-catalyzed borylation sequence. The key to achieve this operatically simple process is the use of Pd catalysis, which could tolerate the solvent and acidic conditions used in the thianthrenation step. This protocol features mild conditions, broad functional group tolerance, and simple manipulations, and is suitable for late-stage functionalization of a wide range of pharmaceuticals and complex bioactive molecules.
Synthesis of boron-containing primary amines
Chung, Sheng-Hsuan,Lin, Ting-Ju,Hu, Qian-Yu,Tsai, Chia-Hua,Pan, Po-Shen
, p. 12346 - 12367 (2013/11/06)
In this study, boron-containing primary amines were synthesized for use as building blocks in the study of peptoids. In the first step, Gabriel synthesis conditions were modified to enable the construction of seven different aminomethylphenyl boronate esters in good to excellent yields. These compounds were further utilized to build peptoid analogs via an Ugi four-component reaction (Ugi-4CR) under microwave irradiation. The prepared Ugi-4CR boronate esters were then successfully converted to the corresponding boronic acids. Finally, the peptoid structures were successfully modified by cross-coupling to aryl/heteroaryl chlorides via a palladium-mediated Suzuki coupling reaction to yield the corresponding derivatives in moderate to good yields.
METHOD FOR THE PRODUCTION OF LOSARTAN
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Page/Page column 20; 32, (2008/06/13)
The invention relates to a novel method for the production of losartan, an imidazol derivative with the chemical name 2-n-butyl-4-chloro-5-hydroxymethyl-1-{[2'-(1H-tetrazol-5-yl)biphenyl-4-]methyl}imidazol and the pharmacologically active salts thereof. The invention also relates to novel intermediate products which are suitable for the production of losartan, and to novel methods for the production of intermediate compounds which are suitable for the production of losartan. One aspect of the invention is a method for the production of a compound of general formula (I), which can arise as an intermediate step in the inventive representation of losartan.
