768-60-5Relevant academic research and scientific papers
Electrochemical Fluorination of Vinyl Boronates through Donor-Stabilized Vinyl Carbocation Intermediates**
Wigman, Benjamin,Lee, Woojin,Wei, Wenjing,Houk, Kendall N.,Nelson, Hosea M.
supporting information, (2022/02/10)
The electrochemical generation of vinyl carbocations from alkenyl boronic esters and boronates is reported. Using easy-to-handle nucleophilic fluoride reagents, these intermediates are trapped to form fully substituted vinyl fluorides. Mechanistic studies support the formation of dicoordinated carbocations through sequential single-electron oxidation events. Notably, this electrochemical fluorination features fast reaction times and Lewis acid-free conditions. This transformation provides a complementary method to access vinyl fluorides with simple fluoride salts such as TBAF.
Preparation and properties of high birefringence phenylacetylene isothiocyanato-based blend liquid crystals
He, Zemin,Wang, Haiyang,Zhang, Huimin,Zhang, Yongming,Zhao, Yang,Zhao, Yuzhen
, (2022/04/03)
A series of compounds of with high birefringence containing alkoxy–phenylacetylene–isothiocyanato structure were synthesized and characterized. The chemical structures of these compounds were confirmed by FT-IR and 1H-NMR, and transition temperatures and birefringence were measured. One of these compounds with good liquid crystal property and high birefringence was mixed with host liquid crystal to form blend liquid crystal. The effects of the concentration of the compound on phase temperature range, birefringence, resistivity, dielectric anisotropy and photoelectric properties were discussed. The results showed that blend liquid crystal (with 7 wt% compound) exhibited excellent comprehensive performance.
Acetylenic Replacement of Albicidin's Methacrylamide Residue Circumvents Detrimental E/Z Photoisomerization and Preserves Antibacterial Activity
Behroz, Iraj,Kleebauer, Leonardo,Hommernick, Kay,Seidel, Maria,Gr?tz, Stefan,Mainz, Andi,Weston, John B.,Süssmuth, Roderich D.
, p. 9077 - 9086 (2021/05/27)
The natural product albicidin is a highly potent inhibitor of bacterial DNA gyrase. Its outstanding activity, particularly against Gram-negative pathogens, qualifies it as a promising lead structure in the search for new antibacterial drugs. However, as we show here, the N-terminal cinnamoyl moiety of albicidin is susceptible to photochemical E/Z isomerization. Moreover, the newly formed Z isomer exhibits significantly reduced antibacterial activity, which hampers the development and biological evaluation of albicidin and potent derivatives thereof. Hence, we synthesized 13 different variants of albicidin in which the vulnerable para-coumaric acid moiety was replaced; this yielded photostable analogues. Biological activity assays revealed that diaryl alkyne analogues exhibited virtually undiminished antibacterial efficacy. This promising scaffold will therefore serve as a blueprint for the design of a potent albicidin-based drug.
Synthesis and Photochemical Application of Hydrofluoroolefin (HFO) Based Fluoroalkyl Building Block
Varga, Bálint,Tóth, Balázs L.,Béke, Ferenc,Csenki, János T.,Kotschy, András,Novák, Zoltán
supporting information, p. 4925 - 4929 (2021/07/01)
A novel fluoroalkyl iodide was synthesized on multigram scale from refrigerant gas HFO-1234yf as cheap industrial starting material in a simple, solvent-free, and easily scalable process. We demonstrated its applicability in a metal-free photocatalytic ATRA reaction to synthesize valuable fluoroalkylated vinyl iodides and proved the straightforward transformability of the products in cross-coupling chemistry to obtain conjugated systems.
Cu-mediated or metal-free alkylation of gem-dibromoalkenes with tertiary, secondary and primary alkyl Grignard reagents
Deng, Yupian,Zhang, Xuxue,Liu, Chuan,Cao, Song
, (2021/01/18)
A novel copper-mediated or transition-metal-free alkylation of gem-dibromoalkenes with tertiary, secondary and primary alkyl Grignard reagents was described. The outcomes of these reactions were found to be highly dependent on the reaction conditions and
Synthesis of alkynes under dry reaction conditions
Rao, Maddali L.N.,Shamim Islam, Sk
supporting information, (2021/04/19)
An easy synthetic method was developed under dry reaction conditions for the preparation of terminal alkynes from 1,1-dibromoalkenes and in the presence of succinimide which acts as a nucleophile and proton donor. It was demonstrated with the synthesis of a broad spectrum of terminal alkynes and extended to synthesize internal alkynes under tandem reaction conditions.
Design, synthesis, antileishmanial, and antifungal biological evaluation of novel 3,5-disubstituted isoxazole compounds based on 5-nitrofuran scaffolds
Trefzger, Ozildéia S.,Barbosa, Natália V.,Scapolatempo, Renata L.,das Neves, Amarith R.,Ortale, Maria L. F. S.,Carvalho, Diego B.,Honorato, Ant?nio M.,Fragoso, Mariana R.,Shuiguemoto, Cristiane Y. K.,Perdomo, Renata T.,Matos, Maria F. C.,Chang, Marilene R.,Arruda, Carla C. P.,Baroni, Adriano C. M.
, (2019/12/27)
Nineteen 3,5-disubstituted-isoxazole analogs were synthesized based on nitrofuran scaffolds, by a [3 + 2] cycloaddition reaction between terminal acetylenes and 5-nitrofuran chloro-oxime. The compounds were obtained in moderate to very good yields (45–91%). The antileishmanial activity was assayed against the promastigote and amastigote forms of Leishmania (Leishmania) amazonensis. Alkylchlorinated compounds 14p–r were active on both the promastigote and amastigote forms, with emphasis on compound 14p, which showed strong activity against the amastigote form (IC50 = 0.6 μM and selectivity index [SI] = 5.2). In the alkyl series, compound 14o stands out with an IC50 = 8.5 μM and SI = 8.0 on the amastigote form. In the aromatic series, the most active compounds were those containing electron-donor groups, such as trimethoxy isoxazole 14g (IC50 = 1.2 μM and SI = 20.2); compound 14h, with IC50 = 7.0 μM and SI = 6.1; and compound 14j containing the 4-SCH3 group, with IC50 = 5.7 μM and SI = 10.2. In addition, the antifungal activity of 19 nitrofuran isoxazoles was evaluated against five strains of Candida (C. albicans, C. parapsilosis, C. krusei, C. tropicalis, and C. glabrata). Eleven isoxazole derivatives were active against C. parapsilosis, and compound 14o was found to be the most active (minimal inhibitory concentration [MIC] = 3.4 μM) for this strain. Compound 14p was active against all the strains tested, with an MIC = 17.5 μM for C. glabrata, lower than that of the fluconazole used as the reference drug.
Preparation of dendritic carboranyl glycoconjugates as potential anticancer therapeutics
Beriha, Swaraj Kumar,Dash, Barada P.,Jena, Bibhuti Bhusan,Mahanta, Chandra Sekhara,Nayak, Bismita,Satapathy, Rashmirekha,Swain, Biswa Ranjan
, p. 34764 - 34774 (2020/10/13)
A series of carborane-appended glycoconjugates containing three and six glucose and galactose moieties have been synthesizedviaCu(i)-catalyzed azide-alkyne [3 + 2] click cycloaddition reaction. The carboranyl glycoconjugates containing three glucose and g
Donor-acceptor substituted benzo-, naphtho- and phenanthro-fused norbornadienes
Fernandez, Lorette,Mans?, Mads,Moth-Poulsen, Kasper,Nielsen, Mogens Br?ndsted,Wang, Zhihang
, (2020/01/31)
The photochromic norbornadiene/quadricyclane (NBD/QC) couple has found interest as a molecular solar thermal energy (MOST) system for storage of solar energy. To increase the energy difference between the two isomers, we present here the synthesis of a selection of benzo-fused NBD derivatives that contain an aromatic unit, benzene, naphthalene or phenanthrene, fused to one of the NBD double bonds, while the carbon atoms of the other double bond are functionalized with donor and acceptor groups. The synthesis protocols involve functionalization of benzo-fused NBDs with bromo/chloro substituents followed by a subjection of these intermediates to a cyanation reaction (introducing a cyano acceptor group) followed by a Sonogashira coupling (introducing an arylethynyl donor group, -C≡CC6H4NMe2 or -C≡CC6H4OMe). While the derivatives have good absorption properties in the visible region (redshifted relative to parent system) in the context of MOST applications, they lack the ability to undergo NBD-to-QC photoisomerization, even in the presence of a photosensitizer. It seems that loss of aromaticity of the fused aromatics is too significant to allow photoisomerization to occur. The concept of destroying aromaticity of a neighboring moiety as a way to enhance the energy density of the NBD/QC couple thus needs further structural modifications, in the quest for optimum MOST systems.
Synthesis of Phenanthrenes via Palladium-Catalyzed Three-Component Domino Reaction of Aryl Iodides, Internal Alkynes, and o-Bromobenzoic Acids
Deng, Guobo,Liang, Yun,Luo, Xiai,Yang, Xiumei,Yang, Yuan,Yang, Yuzhong,Zhou, Liwei
supporting information, p. 1223 - 1230 (2020/04/15)
A new palladium-catalyzed domino alkyne insertion/C-H activation/decarboxylation sequence has been developed, which provides an efficient approach for synthesizing a variety of functionalized phenanthrenes in moderate to good yields. The method shows broad substrate scope and good functional group tolerance by employing readily available materials, including aryl iodides, internal alkynes, and o-bromobenzoic acids, as three-component coupling partners.
