- Facile Synthesis of Hydroxy-Substituted Thiacrown Ethers via Nucleophilic Ring Opening of Epoxides
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The title thiacrown ethers were prepared in a one-step procedure to give a series of unique macrocycles possessing two unsubstituted hydroxy groups that can be easily functionalized. In addition, epoxides and macrocycles derived from Cookson's birdcage diketone, were prepared. The nucleophilic ring opening of epoxides synthesis can be classified in the frame of click chemistry. Surprisingly, some of the prepared allyl substituted polyglycols as well as bis-epoxides, especially sulfur analogues, were prepared for the first time.
- Stefaniak, Monika,Romański, Jaros?aw
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p. 2214 - 2220
(2019/05/10)
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- Polyoxyethylene ether carboxylic acid dimeric surfactant type drag reducer as well as preparation method and application thereof
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The invention discloses a polyoxyethylene ether carboxylic acid dimeric surfactant type drag reducer as well as a preparation method and application thereof. The polyoxyethylene ether carboxylic aciddimeric surfactant type drag reducer has a structure formula m=2, 3, 4, and n=1, 2, 3. The drag reducer disclosed by the invention is a dimeric surfactant type drag reducer which has a head group of carboxylic acid, and the head group has the advantages of being very good in temperature resistance, salt resistance, environment protection and the like, and is capable of overcoming influence of a high-salt environment upon drag reduction performance, so that the drag reducer disclosed by the invention is high in drag reduction efficiency, good in shearing resistance, long-lasting and stable in drag reduction rate and good in salt resistance; and polyoxyethylene ether carboxylic acid dimeric surfactants of different mass concentrations are dissolved into water, a drag reduction solution whichis high in drag reduction efficiency, good in shearing resistance, long-lasting and stable in drag reduction rate and good in salt resistance can be prepared without any other compounded chemical reagent, solution blending steps are simple, the drag reducer is very convenient to use, and meanwhile, the salt resistance is greatly improved.
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Paragraph 0114; 0117-0118; 0123; 0126-0127; 0132; 0135-0136
(2019/09/13)
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- Application of HPLC for the screening of separation of new macrocyclic systems
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The efficient synthesis of new macrocyclic systems via nucleophilic ring opening reaction of epoxides by thiols was described. Initially new macrocyclic compounds were obtained as a mixture of diastereomers. Preparative thin layer chromatography was applied to separate meso and pairs of enantiomer. The identification of products using a chiral HPLC column and mass spectroscopy was utilized.
- Stefaniak, Monika,Romański, Jaros?aw
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p. 245 - 248
(2017/01/22)
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- One-pot Three Component Synthesis of ω-(oxathiolan-2-thion-5-yl)-α-oxazolidin-2-ones
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We report a practical and one-pot synthesis of novel series of ω-(oxathiolan-2-thione-5-yl)-α- oxazolidin-2-ones (3a-h). The obtained compounds have been designed, synthesized via reaction of oligoethylene glycols diglycidyl ethers, isocyanate and carbon disulfide in the presence of catalytic amount of lithium bromide. A variety of important oxazolidinone derivatives can be obtained from simple starting materials in good yields and the biological activity of these new products will be investigated in complementary study.
- Ghrab, Saad,Aroua, Lotfi,Beji, Mohamed
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p. 2397 - 2404
(2017/07/25)
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- Solvent-free synthesis of dihydroxy dithiacrown ethers
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The solvent-free reaction of oligoethylene glycol diglycidyl ethers with dimercaptoethane in the presence of benzyltrimethylammonium hydroxide (Triton B) gave, via regiospecific epoxide opening reactions, dihydroxy dithiacrown ethers in excellent yields and in short reaction times.
- Zoghlami, Houcine,Romdhani-Younes, Moufida,Chaabouni, Mohamed Moncef,Baklouti, Ahmed
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scheme or table
p. 881 - 883
(2011/03/20)
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- Dinuclear macrocyclic polyamine zinc(II) complexes linked with flexible spacers: Synthesis, characterization, and DNA cleavage
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Dinuclear macrocyclic polyamine zinc(II) complexes, which have two cyclen groups linked by flexible spacers, have been synthesized as DNA cleavage agents. The structures of these new dinuclear complexes are consistent with the data obtained from elemental analysis, MS and 1H NMR spectroscopy. The catalytic activity of these dinuclear complexes on DNA cleavage was studied. The results showed that the dinuclear zinc(II) complexes can catalyze the cleavage of supercoiled DNA (pUC 19 plasmid DNA) (Form I) under physiological conditions to produce selectively nicked DNA (Form II).
- Peng, Wei,Liu, Pei-Yan,Jiang, Ning,Lin, Hong-Hui,Zhang, Guo-Lin,Liu, Yi,Yu, Xiao-Qi
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p. 374 - 385
(2008/02/01)
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- Polyoxyalkylene substituted and bridged triazine, benzotriazole and benzophenone derivatives as UV absorbers
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Triazine, benzotriazole and benzophenone derivatives which are substituted or bridged with polyoxyalkylene groups, according to claim1,and their use as UV absorbers, especially in photographic materials, in inks, including inkjet inks and printing inks, in transfer prints, in paints and varnishes, organic polymeric materials, plastics, rubber, glass, packaging materials, in sunscreens of cosmetic preparations and in skin protection compositions.
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Page column 68
(2010/11/29)
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