6286-30-2Relevant articles and documents
Catalyst-Free 1,2-Dibromination of Alkenes Using 1,3-Dibromo-5,5-dimethylhydantoin (DBDMH) as a Bromine Source
Wang, Lei,Zhai, Lele,Chen, Jinyan,Gong, Yulin,Wang, Peng,Li, Huilin,She, Xuegong
supporting information, p. 3177 - 3183 (2022/02/23)
A direct 1,2-dibromination method of alkenes is realized using 1,3-dibromo-5,5-dimethylhydantoin (DBDMH) as a bromine source. This reaction proceeds under mild reaction conditions without the use of a catalyst and an external oxidant. Various sorts of alkene substrates are transformed into the corresponding 1,2-dibrominated products in good to excellent yields with broad substrate scope and exclusive diastereoselectivity. This method offers a green and practical approach to synthesize vicinal dibromide compounds.
Synthesis method of o-Dibromo compound
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Paragraph 0042-0051, (2022/01/04)
The present invention discloses a synthesis method of o-dibromo compounds, said synthesis method comprising the following steps: preparation of olefins, brominated salts and a mixed solution of bromate; to the mixed solution of dropwise addition of hydrochloric acid solution for reaction; to the end of the reaction, the extraction of o-dibromo compounds in the reaction product; the synthesis method to inexpensive brominated salts (industrial or recycled brominated salts) and bromate as a bromine source, enhance the full use of applicable resources; after the end of the reaction after a simple filtration treatment to obtain a sufficient purity of the product, It can reduce production costs; at the same time, facilitate the transportation and storage of raw materials, and improve the working environment. The synthesis method of the present invention is simple and easy to operate, high safety, small pollution, simple post-treatment, low production cost, product yield and purity can meet the production needs, is both cost advantages and safety and environmental advantages of the industrializable process.
Chemical validation of a druggable site on Hsp27/HSPB1 using in silico solvent mapping and biophysical methods
Makley, Leah N.,Johnson, Oleta T.,Ghanakota, Phani,Rauch, Jennifer N.,Osborn, Delaney,Wu, Taia S.,Cierpicki, Tomasz,Carlson, Heather A.,Gestwicki, Jason E.
, (2021/02/09)
Destabilizing mutations in small heat shock proteins (sHsps) are linked to multiple diseases; however, sHsps are conformationally dynamic, lack enzymatic function and have no endogenous chemical ligands. These factors render sHsps as classically “undruggable” targets and make it particularly challenging to identify molecules that might bind and stabilize them. To explore potential solutions, we designed a multi-pronged screening workflow involving a combination of computational and biophysical ligand-discovery platforms. Using the core domain of the sHsp family member Hsp27/HSPB1 (Hsp27c) as a target, we applied mixed solvent molecular dynamics (MixMD) to predict three possible binding sites, which we confirmed using NMR-based solvent mapping. Using this knowledge, we then used NMR spectroscopy to carry out a fragment-based drug discovery (FBDD) screen, ultimately identifying two fragments that bind to one of these sites. A medicinal chemistry effort improved the affinity of one fragment by ~50-fold (16 μM), while maintaining good ligand efficiency (~0.32 kcal/mol/non-hydrogen atom). Finally, we found that binding to this site partially restored the stability of disease-associated Hsp27 variants, in a redox-dependent manner. Together, these experiments suggest a new and unexpected binding site on Hsp27, which might be exploited to build chemical probes.
Stable and Highly Regioselective Anionic Polymerization of (Z)-1-Phenyl[3]dendralene
Miya, Masamitsu,Takagi, Tsukasa,Takenaka, Katsuhiko,Toda, Tomoyuki
, p. 4326 - 4332 (2021/05/29)
The anionic polymerization of (Z)-1-phenyl[3]dendralene (1Z-P3D) in THF with potassium naphthalenide (K-Naph) as an initiator was investigated. At -78 °C, a polymer of predictable molecular weight and narrow molecular-weight distribution (Mw/Mn = 1.26) was obtained quantitively in 24 h. The active chain-end carbanion derived from 1Z-P3D was significantly stabilized by conjugation with a phenyl substituent at the C1 position of the monomer; side reactions such as nucleophilic addition to the double bond in other polymer main chains were not observed over a wide temperature range (-78-0 °C). The microstructure of the obtained poly(1Z-P3D) contained a predominant amount of the 1,4 structure (>90%). Thus, the polymerizability of 1Z-P3D was different from that of previously reported 2-phenyl[3]dendralene (P3D), in terms of the nucleophilicity of the active chain end and regioselectivity in the propagation reaction.
Crystal structure, characterization, Hirshfeld surface analysis and DFT studies of two [propane 3-bromo-1-(triphenyl phosphonium)] cations containing bromide (I) and tribromide (II) anions: The anion (II) as a new brominating agent for unsaturated compounds
Nokhbeh, Seyed Reza,Gholizadeh, Mostafa,Salimi, Alireza,Sparkes, Hazel A.
, p. 542 - 554 (2019/06/18)
In this study, propane 3-bromo-1- (triphenyl phosphonium) bromide, I, and propane 3-bromo-1- (triphenyl phosphonium) tribromide, II, (II as a new brominating agent) were synthesized and characterized by 1H NMR, 13C NMR, 31P NMR, FT-IR, spectroscopy, Thermogravimetric Analysis, Differential thermal analysis, Differential scanning calorimetry and single crystal X-ray analysis. Density functional theory calculations (energy, structural optimization and frequencies, Natural Bond Orbital, absorption energy and binding energy) were performed by using B3LYP/6-311 G++ (d, p) level of theory. Hirshfeld surface analysis and fingerprint plots were utilized to investigate the role of bromide and tribromide anions on the crystal packing structures of title compounds. The results revealed that the change of accompanying anionic moiety can affect the directional interactions of C-H?Br hydrogen bonds between anionic and cationic units in which the H?Br with a proportion of 53.8% and 40.9% have the major contribution in the stabilization of crystal structures of I and II, respectively. Furthermore, the thermal stability of new brominating agent II with tribromide anion was compared with compound I with bromide anion. Nontoxicity, short reaction time, thermal stability, simple working up and high yield are some of the advantages of these salts.
A Facile Access to trans -3-Styryl-4-hydrazinocyclopentenes via Palladium-Catalyzed Ring Opening of Diazanorbornenes with (Z)-β-Bromostyrenes/2,3-Dibromohydrocinnamic Acids
Saranya,Chand, S. Sarath,Gopalan, Greeshma,Jijitha,Radhakrishnan
, p. 184 - 192 (2017/10/13)
trans -3-Styryl-4-hydrazinocyclopentenes have been synthesized via palladium-catalyzed desymmetrization of diazanorbornenes with (Z)-β-bromostyrenes. The reaction also works well with (Z)-β-bromostyrenes generated in situ from 2,3-dibromohydrocinnamic acids. The synthesized hydrazinocyclopentenes provide an easy route towards synthetic intermediates of many scaffolds of biological potential.
Ir-Catalyzed Intramolecular Transannulation/C(sp2)-H Amination of 1,2,3,4-Tetrazoles by Electrocyclization
Das, Sandip Kumar,Roy, Satyajit,Khatua, Hillol,Chattopadhyay, Buddhadeb
supporting information, p. 8429 - 8433 (2018/07/09)
An efficient strategy for the intramolecular denitrogenative transannulation/C(sp2)-H amination of 1,2,3,4-tetrazoles bearing C8-substituted arenes, heteroarenes, and alkenes is described. The process involves the generation of the metal-nitrene intermediate from tetrazole by the combination of [CpIrCl2]2 and AgSbF6. It has been shown that the reaction proceeds via an unprecedented electrocyclization process. The method has been successfully applied for the synthesis of a diverse array of α-carbolines and 7-azaindoles.
Carbene-catalyzed LUMO activation of alkyne esters for access to functional pyridines
Mou, Chengli,Wu, Jichang,Huang, Zhijian,Sun, Jun,Jin, Zhichao,Chi, Yonggui Robin
supporting information, p. 13359 - 13362 (2017/12/26)
A carbene-catalyzed LUMO activation of α,β-unsaturated alkyne esters is reported. This catalytic process allows for effective reactions of alkyne esters with enamides to synthesize functional pyridines via simple protocols. A previously unexplored unsaturated alkyne acyl azolium intermediate is involved in the key step of the reaction.
Chloro/bromotrimethylsilane-Cu(NO3)2·3H2O: Safe and efficient reagent system for the decarboxylative ipso-nitration and dibromination of cinnamic acids
Roshandel, Sahar,Gurung, Laxman,Mathew, Thomas,Prakash, G.K. Surya
supporting information, p. 2842 - 2845 (2017/06/27)
Further synthetic potential of halotrimethylsilane-nitrate salt mixture is revealed. A mixture of TMSX-Cu(NO3)2·3H2O system is found to be an efficient reagent system for both the decarboxylative nitration (ipso-nitration) when X?=?Cl, and dibromination of cinnamic acids, with X?=?Br, under mild conditions. The reactions are safe and simple, affording the corresponding products (E)-β-nitrostyrenes, and anti-2,3-dibromo-3-phenylpropanoic acids in high yields with high selectivity in a relatively short time. Use of hazardous and toxic nitrating systems such as acetyl nitrate and brominating agents such as molecular bromine can be avoided.
Palladium-Catalyzed Two-Component Domino Coupling Reaction of (Z)-β-Bromostyrenes with Norbornenes: Synthesis of 1,5-Enynes
Mao, Jiangang,Li, Huifang,Wen, Herui,Li, Min,Fan, Xiaolin,Bao, Weiliang
supporting information, p. 1873 - 1879 (2016/07/06)
Polyfunctional molecules, 1,5-enynes, have been achieved via a palladium(0)-catalyzed domino coupling reaction of (Z)-β-bromostyrenes with norbornenes in the presence of cesium carbonate and N,N-dimethylformamide. The process involves a double Heck-type procedure, two-fold C(sp2) H activation and formation of two carbon-carbon bonds. There are possibilities of diversified transformation for the domino coupling of (Z)-β-bromostyrenes with norbornenes, the procedure is successfully driven to 1,5-enynes via accurate adjustment of the reaction conditions. (Figure presented.) .
