- Synthesis and Structure of 1-Substituted Semithioglycolurils
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Two methods for the synthesis of previously unavailable 1-substituted semithioglycolurils were developed. These methods consist of the cyclocondensation of 1-substituted ureas with 4,5-dihydroxy- or 4,5-dimethoxyimidazolidine-2-thione or glyoxal, followed by the reaction of the resulting 1-substituted 4,5-dihydroxyimidazolidine-2-ones with HSCN in a two-step one-pot procedure. Two of the desired semithioglycolurils were obtained as conglomerates.
- Baranov, Vladimir V.,Galochkin, Anton A.,Kravchenko, Angelina N.,Makhova, Nina N.,Nelyubina, Yulia V.
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p. 2563 - 2571
(2020/09/07)
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- Industrial preparation method of beta-hydroxyethyl urea
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The invention relates to an industrial preparation method of beta-hydroxyethyl urea. The technical scheme includes that urea and 1-ethanol amine react in a reactor, 85% methanoic acid solution absorbsgenerated ammonia gas, reaction is finished, temperature is reduced to 70-80 DEG C, crystallization solvents are added and transferred into a crystallization kettle after heat insulation and hot filtration, the temperature is slowly reduced to 5 DEG C and kept for 3 hours, a large quantity of crystals are separated out, discharged to a centrifugal machine and washed by organic solvents until pH (potential of hydrogen) is 7-8, and vacuum drying is performed to obtain the beta-hydroxyethyl urea. The crystallization solvents are directly added to post-treatment, mechanical impurities led in by raw materials are removed by hot filtration, the crystals are directly separated out in a cooling manner by an 'all in one pot' method, technological processes are simplified, product quality is remarkably improved, high-quality use requirements of cosmetic grade raw materials are met, irritating odor and urea residues are avoided in long-time storage, and the problems of poor product stability andeasiness in discoloration caused by pH value change are solved.
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Paragraph 0022; 0016; 0024-0054; 0059-0064
(2019/03/08)
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- The ethylenically unsaturated group-containing isocyanate compound
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PROBLEM TO BE SOLVED: To provide a production method capable of obtaining an ethylenically unsaturated group-containing isocyanate compound with high yield, which is excellent in safety to human bodies or environments without using phosgene and in which the production processes and production facilities are simplified.SOLUTION: There is a method for producing an ethylenically unsaturated group-containing isocyanate compound which produces a compound having an ethylenically unsaturated bond and an isocyanate group in the molecule using an amino alcohol as a raw material, wherein the method has a step of producing a cyclic compound having a urethane bond in the molecule as an intermediate.
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Paragraph 0031; 0131; 0135
(2019/01/04)
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- PROCESS FOR STRAIGHTENING KERATIN FIBRES WITH A HEATING MEANS AND DENATURING AGENTS
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The invention relates to a process for straightening keratin fibres, comprising: (i) a step in which a straightening composition containing at least two denaturing agents is applied to the keratin fibres, (ii) a step in which the temperature of the keratin fibres is raised, using a heating means, to a temperature of between 110 and 250° C.
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- Synthesis of 2-monofunctionalized 2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7- diones
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New (1R*,5S*)-2-R-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7- diones containing the terminal carboxy or hydroxy group in the substituent R were synthesized by cyclocondensation of 4,5-dihydroxyimidazolidin-2-one with 1-R-ureas. Single-crystal X-ray diffraction analysis showed that 2-carboxyethyl-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione crystallizes as a racemate.
- Kravchenko,Maksareva,Belyakov,Sigachev,Chegaev,Lyssenko,Lebedev,Makhova
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p. 192 - 197
(2007/10/03)
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- Production of aminoethyl hydrogen sulfate
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Aminoethyl hydrogen sulfate is produced under acidic conditions by reating ammonium bisulfate or ammonium sulfate with an ethylene compound represented by either of the formulae: STR1 where A represents C=C or C=S.
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- PTERIDINES, LXX - SYNTHESIS AND PROPERTIES OF 1,8-ALKYLENE-BRIDGED LUMAZINES
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A new type of lumazine derivatives (24-30) with a 1,8-alkylene bridge has been synthesized to study the protonation site in lumazine (1) itself.Comparisons of UV-data, however, do not allow a clear decision in this respect but indicate possibly the presence of a mixture of at least two cationic species.The structures of the newly synthesized compounds have been proven by UV- and NMR-spectra as well as pKa measurements and elementary analyses. 8-β-Hydroxyethyl-7-oxo-7,8-dihydrolumazines (15-17) show an easy cyclization to the corresponding 1,8-ethano-bridged derivatives 18-20 on boiling with DMF.
- Uhlmann, Eugen,Pfleiderer, Wolfgang
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p. 437 - 453
(2007/10/02)
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