185259-36-3Relevant academic research and scientific papers
Imidazole synthesis by transition metal free, base-mediated deaminative coupling of benzylamines and nitriles
Das, Uttam Kumar,Shimon, Linda J. W.,Milstein, David
, p. 13133 - 13136 (2017)
A transition metal free, straightforward synthetic method for the preparation of substituted imidazoles is reported herein. Base promoted, deaminative coupling of benzylamines with nitriles results in the one-step synthesis of 2,4,5-trisubstituted imidazoles with liberation of ammonia. This protocol provides a practical strategy for the synthesis of valuable imidazole derivatives from readily available starting materials.
Transforming Sphingosine Kinase 1 Inhibitors into Dual and Sphingosine Kinase 2 Selective Inhibitors: Design, Synthesis, and in Vivo Activity
Childress, Elizabeth S.,Kharel, Yugesh,Brown, Anne M.,Bevan, David R.,Lynch, Kevin R.,Santos, Webster L.
, p. 3933 - 3957 (2017)
Sphingosine 1-phosphate (S1P) is a pleiotropic signaling molecule that interacts with its five G-protein coupled receptors (S1P1-5) to regulate cell growth and survival and has been implicated in a variety of diseases including cancer and sickle cell disease. As the key mediators in the synthesis of S1P, sphingosine kinase (SphK) isoforms 1 and 2 have attracted attention as viable targets for pharmaceutical inhibition. In this article, we describe the design, synthesis, and biological evaluation of aminothiazole-based guanidine inhibitors of SphK. Surprisingly, combining features of reported SphK1 inhibitors generated SphK1/2 dual inhibitor 20l (SLC4011540) (hSphK1 Ki = 120 nM, hSphK2 Ki = 90 nM) and SphK2 inhibitor 20dd (SLC4101431) (Ki = 90 nM, 100-fold SphK2 selectivity). These compounds effectively decrease S1P levels in vitro. In vivo administration of 20dd validated that inhibition of SphK2 increases blood S1P levels.
Convenient two-step synthesis of highly functionalized benzo-fused 1,4-diazepin-3-ones and 1,5-diazocin-4-ones by sequential Ugi and intramolecular SNAr reactions
Vézina-Dawod, Simon,Gerber, Nicolas,Liang, Xinxia,Biron, Eric
, p. 6347 - 6355 (2017)
Benzodiazepinones are an important family of heterocycles with very attractive pharmacological properties and peptidomimetic abilities. We report herein a rapid and efficient two-step synthesis of polysubstituted 1,4-benzodiazepin-3-ones and 1,5-benzodiazocin-4-ones using a multicomponent condensation/cyclization strategy. The approach uses an Ugi four-component reaction to condense readily available Nα-Fmoc-amino acids, amines and isocyanides with a 2-fluorobenzaldehyde derivative followed by a one-pot Fmoc-group removal, intramolecular aromatic nucleophilic substitution for ring closure and side chain deprotection. The described method gives access to benzo-fused 7- and 8-membered rings bearing a wide variety of functionalized substituents and was applied to efficiently prepare tri- and tetrasubstituted 1,4-benzodiazepin-3-ones and 1,5-benzodiazocin-4-ones in high yields in two straightforward steps.
Ammonium Chloride-Promoted Rapid Synthesis of Monosubstituted Ureas under Microwave Irradiation
Lan, Chunling Blue,Auclair, Karine
supporting information, p. 5135 - 5146 (2021/10/19)
Monosubstituted ureas are important scaffolds in organic chemistry. They appear in various biologically active compounds and serve as versatile precursors in synthesis. Monosubstituted ureas were originally prepared using toxic and hazardous phosgene equivalents. Modern methods include transamidation of urea and nucleophilic addition to cyanate salts, both of which suffer from a narrow substrate scope due to the need for a strong acid and prolonged reaction times. We hereby report that ammonium chloride can promote the reaction between amines and potassium cyanate to generate monosubstituted ureas in water. This method proceeds rapidly under microwave irradiation and tolerates a broad range of functional groups. Unlike previous strategies, it is compatible with other nucleophiles, acid-labile moieties, and most of the common protecting groups. The products precipitate out of solution, allowing facile isolation without column chromatography.
Immobilized palladium nanoparticles on a cyclodextrin-polyurethane nanosponge (Pd-CD-PU-NS): An efficient catalyst for cyanation reaction in aqueous media
Khajeh Dangolani, Soheila,Sharifat, Sara,Panahi, Farhad,Khalafi-Nezhad, Ali
supporting information, p. 256 - 265 (2019/06/07)
Immobilized palladium nanoparticles on a cyclodextrin-polyurethane nanosponge (Pd-CD-PU-NS) were found to be an efficient heterogeneous catalyst in the cyanation reaction of aryl halides in aqueous media. This catalyst system is containing palladium nanoparticles with a size of ～7 nm. Moreover, the CD-PU-NS support formed microsphere-shaped structures with a size of ～100–200 nm. The TEM images show that Pd nanoparticles were formed in near spherical shape morphology and were immobilized in the structure of the CD-PU-NS support. Under our optimized reaction conditions, aryl cyanides were obtained in high yields in the presence of the Pd-CD-PU-NS catalyst. Our results demonstrated that the Pd-CD-PU-NS catalyst is highly effective in the cyanation reaction in aqueous media. Furthermore, the catalyst could be simply extracted from the reaction mixture, providing an efficient methodology for the synthesis of aryl cyanides. The Pd-CD-PU-NS catalyst could be recycled four times with almost consistent catalytic efficiency.
Urea-based organocatalyst catalyzed direct C–H bond arylations of unactivated arenes
Zhao, Huaiqing,Xu, Xiangwen,Wu, Wei,Zhang, Wei,Zhang, Yunxian
, p. 95 - 99 (2018/04/24)
A simple 1,3-diethylurea was demonstrated to catalyze transition-metal-free arylations of unactivated aromatic C–H bonds with aryl iodides in the presence of t-BuOK. A broad range of aryl iodides with different arenes could couple in moderate to excellent yields. The mechanistic experiment results indicated that the radical is involved in this transformation.
From Anilines to Aryl Ethers: A Facile, Efficient, and Versatile Synthetic Method Employing Mild Conditions
Wang, Dong-Yu,Yang, Ze-Kun,Wang, Chao,Zhang, Ao,Uchiyama, Masanobu
, p. 3641 - 3645 (2018/03/13)
We have developed a simple and direct method for the synthesis of aryl ethers by reacting alcohols/phenols (ROH) with aryl ammonium salts (ArNMe3+), which are readily prepared from anilines (ArNR′2, R′=H or Me). This reaction proceeds smoothly and rapidly (within a few hours) at room temperature in the presence of a commercially available base, such as KOtBu or KHMDS, and has a broad substrate scope with respect to both ROH and ArNR′2. It is scalable and compatible with a wide range of functional groups.
Solid-phase syntheses of peptoids using Fmoc-protected N-substituted glycines: The synthesis of (retro)peptoids of leu-enkephalin and substance P
Kruijtzer, John A.W.,Hofmeyer, Lovina J.F.,Heerma, Wigger,Versluis, Cornelis,Liskamp, Rob M.J.
, p. 1570 - 1580 (2007/10/03)
A particularly interesting class of oligomeric peptidomimetics is formed by the peptoids, which consist of N-substituted glycine residues. A solid- phase synthesis method for peptoids is presented in which these residues are introduced using their Fmoc derivatives. This 'monomer' method allowed the monitored synthesis of relatively large quantities of pure peptoids as well as the translation of, in principle, any peptide into the corresponding peptoid. The required Fmoc-substituted glycines were accessible by convenient synthesis, and a number of monomers including those containing side chains with functional groups have been synthesized. The use of Fmoc monomers also allowed implementation of a solid-phase synthesis protocol on a commercial peptide synthesizer. The method was exempli- fled by the solid-phase syntheses of the (retro)peptoids of Leu-enkephalin and substance P. Mass spectrometric studies of (retro)peptoids were essential for their characterization, and the presence of the B- and Y'- type ions allows sequence analysis. Substance P (retro)peptoids were biologically active. HPLC analysis showed an increased hydrophobicity, and pepsin treatment resulted in greatly reduced degradation compared with the corresponding peptide.
Synthesis of aryl ethers
-
, (2008/06/13)
A method for preparing an aryl ether compound is provided in which an alcohol is reacted with an aromatic compound in the presence of a base, and a transition metal catalyst selected from the group consisting of platinum and nickel to form an aryl ether.
Nickel- vs Palladium-Catalyzed Synthesis of Protected Phenols from Aryl Halides
Mann, Grace,Hartwig, John F.
, p. 5413 - 5418 (2007/10/03)
We report the nickel-catalyzed formation of alkyl and silyl ethers from aryl halides in one step. These ethers can act as precursors to phenols by reaction with Bronsted or Lewis acids or with fluoride. A combination of Ni(COD)2 and DPPF mediates the formation of tert-butyl aryl, methyl aryl, and tert-butyldimethyl silyl aryl ethers efficiently from aryl halides and sodium alkoxides or sodium siloxides under mild reaction conditions. Reactions to form the tert-butyl aryl ethers mediated by nickel complexes have lower turnover numbers than the analogous palladium-catalyzed reactions. However, reactions to form methyl aryl ethers show higher yields when catalyzed by a combination of Ni(COD)2 and BINAP than when catalyzed by BINAP or DPPF and palladium catalyst precursors. Similarly, the formation of silyl aryl ethers occurs in higher yields and under milder conditions when catalyzed by a combination Ni(COD)2 and DPPF than when catalyzed by palladium complexes. We also report improved yields from our previous results for the palladium-catalyzed conversion of aryl halides to tert-butyl aryl ethers.
