3-[(5-Chloro-2-hydroxyphenyl)methyl]-5-[4-(trifluoromethyl)phenyl ]-1,3,4-oxadiazol-2(3H)-one, BMS-191011: Opener of Large-Conductance Ca2+-Activated Potassium (Maxi-K) Channels, Identification, Solubility, and SAR
摘要:
Compound 8a (BMS-191011), an opener of the cloned large-conductance, Ca2+-activated potassium (maxi-K) channel, demonstrated efficacy in in vivo stroke models, which led to its nomination as a candidate for clinical evaluation. Its maxi-K channel opening properties were consistent with its structural topology, being derived by combining elements from other known maxi-K openers. However, 8a suffered from poor aqueous solubility, which complicated elucidation of SAR during in vitro evaluation. The activity of 8a in in vivo stroke models and studies directed toward improving its solubility are reported herein. Enhanced solubility was achieved by appending heterocycles to the 8a scaffold, and a notable observation was made that inclusion of a simple amino group (anilines 8k and 8l) yielded excellent in vitro maxi-K ion channel opening activity and enhanced brain-to-plasma partitioning compared to the appended heterocycles.
Electrochemical Activation of Diverse Conventional Photoredox Catalysts Induces Potent Photoreductant Activity**
作者:Colleen P. Chernowsky、Alyah F. Chmiel、Zachary K. Wickens
DOI:10.1002/anie.202107169
日期:2021.9.20
Herein, we disclose that electrochemical stimulation induces new photocatalytic activity from a range of structurally diverse conventional photocatalysts. These studies uncover a new electron-primed photoredox catalyst capable of promoting the reductive cleavage of strong C(sp2)−N and C(sp2)−O bonds. We illustrate several examples of the synthetic utility of these deeply reducing but otherwise safe
Reductive Amination of Aldehydes and Ketones with Sodium Triacetoxyborohydride. Studies on Direct and Indirect Reductive Amination Procedures<sup>1</sup>
作者:Ahmed F. Abdel-Magid、Kenneth G. Carson、Bruce D. Harris、Cynthia A. Maryanoff、Rekha D. Shah
DOI:10.1021/jo960057x
日期:1996.1.1
triacetoxyborohydride is presented as a general reducing agent for the reductiveamination of aldehydes and ketones. Procedures for using this mild and selective reagent have been developed for a wide variety of substrates. The scope of the reaction includes aliphatic acyclic and cyclic ketones, aliphatic and aromatic aldehydes, and primary and secondary amines including a variety of weakly basic and
N−N Bond Formation Using an Iodonitrene as an Umpolung of Ammonia: Straightforward and Chemoselective Synthesis of Hydrazinium Salts
作者:Arianna Tota、Marco Colella、Claudia Carlucci、Andrea Aramini、Guy Clarkson、Leonardo Degennaro、James A. Bull、Renzo Luisi
DOI:10.1002/adsc.202001047
日期:2021.1.5
The formation of hydrazinium salts by N−N bond formation has typically involved the use of hazardous and difficult to handle reagents. Here, mild and operationally simple conditions for the synthesis of hydrazinium salts are reported. Electrophilic nitrogen transfer to the nitrogen atom of tertiary amines is achieved using iodosylbenzene as oxidant and ammonium carbamate as the N‐source. The resulting
Highly efficient Amination in Neat Water of Benzyl Chlorides with Dialkylformamides Catalysed by <i>N</i>-Heterocyclic Carbene-Palladium(II)-1-Methylimidazole Complex
作者:Wen-Xin Chen、Cai-Yun Zhang、Jian-Mei Lu
DOI:10.3184/174751913x13787959859344
日期:2013.10
Dialkylformamides are excellent N-sources in the amination of benzylchlorides when catalysed by a NHC-Pd(II)-Im complex. In the presence of NaOH and the catalyst, variously substituted benzylchlorides and five different dialkylformamides reacted smoothly to afford the corresponding N,N-dialkyl-benzylamines in good to almost quantitative yields in eco-friendly solvent water at 50 °C within 3 h.
Thiourea‐Catalyzed C−F Bond Activation: Amination of Benzylic Fluorides
作者:Camille Houle、Paul R. Savoie、Clotilde Davies、Damien Jardel、Pier Alexandre Champagne、Brigitte Bibal、Jean‐François Paquin
DOI:10.1002/chem.202001905
日期:2020.8.17
thiourea catalyst and Ti(OiPr)4 as a fluoride scavenger allows the amination of benzylic fluorides to proceed in moderate to excellent yields. Preliminary results with S‐ and O‐based nucleophiles are also presented. DFT calculations reveal the importance of hydrogen bonds between the catalyst and the fluorineatom of the substrate to lower the activation energy during the transition state.
我们描述了第一个硫脲催化的CF键活化。使用硫脲催化剂和Ti(O i Pr)4作为氟化物清除剂可使苄基氟化物的胺化反应以中等至极好的收率进行。还介绍了基于S和O的亲核试剂的初步结果。DFT计算揭示了催化剂和底物氟原子之间氢键对于降低过渡态活化能的重要性。