7635-53-2Relevant academic research and scientific papers
Synthesis method of acetaldehyde alcohol optical active ester
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Paragraph 0024-0026, (2021/05/08)
The invention provides a synthesis method of an acetaldehyde alcohol optical active ester, which comprises the following steps of: reacting L-menthol as a raw material with triphosgene to obtain L-menthyl chloroformate, reacting the L-menthyl chloroformate with 1, 4-cis-butenediol, recrystallizing, and carrying out oxidation reaction under an ozone condition to obtain the acetaldehyde alcohol optical active ester. In the whole synthesis process, the initial raw materials are low in price and easy to obtain, the synthesis process is simple, the synthesis conditions are mild, and the synthesis cost of the acetaldehyde alcohol optical active ester is greatly reduced. The raw materials are good in reaction selectivity and high in atom utilization rate, and the obtained acetaldehyde alcohol optical active ester has high yield and purity. Meanwhile, few three-waste pollutants are generated in the synthesis process, and the method is suitable for industrial large-scale production of the acetaldehyde alcohol optical active ester, so that large-scale synthesis of drugs such as emtricitabine and lamivudine is facilitated.
Spiro Scaffold Chiral Organocatalyst of 3,2′-Pyrrolidinyl Spiro-oxindole Amine and Its Catalytic Evaluation in the Enantioselective Aldol Condensation between 3-(3-Hydroxy-1 H-pyrazol-1-yl)-Oxindole and Paraformaldehyde
Zou, Ying,Huang, Zhi-Cheng,Xiang, Min,Li, Chen-Yi,Li, Xia,Tian, Fang,Wang, Li-Xin
, p. 17371 - 17379 (2021/12/02)
The spiro scaffold chiral organocatalyst of 3,2′-pyrrolidinyl spiro-oxindole amine was successfully prepared from racemic spiro-oxindole amine using l-menthol as a chiral pool in 4 steps in 28%-40% overall yields with at least 99% ee in scale-up preparation, and its catalytic activity was evaluated in the enantioselective aldol condensation between 3-(3-hydroxy-1H-pyrazol-1-yl)-oxindole and paraformaldehyde. The spiro organocatalyst showed superior catalytic activity and selectivity compared with its counterparts, and most substrates offered good to excellent results with up to 96% yield in 96% ee.
Concise synthesis and applications of enantiopure spirobiphenoxasilin-diol and its related chiral ligands
Liu, Tao,Wang, Biqin,Wang, Peng,Wu, Yichen,Xu, Wen-Qiang,Yang, Lei
supporting information, p. 13365 - 13368 (2021/12/17)
The development of chiral architectures for chiral ligand and catalyst discovery is essential for asymmetric catalysis. Herein, we report the concise synthesis of a Si-centered spirocyclic skeleton, spirobiphenoxasilin-diol (SPOSiOL), and its derived chiral ligands. Using the chemical resolution method, the optical SPOSiOL could be obtained in high yield on a gram scale. Preliminary studies indicated that this ligand scaffold has great potential in transition metal-catalyzed asymmetric reactions. This finding further highlights that the Si-centered spirocyclic scaffolds are of great value in asymmetric catalysis. This journal is
Synthetic method of acetaldehyde alcohol optical active ester
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Page/Page column 0038-0039; 0043-0044; 0048-0049, (2021/09/04)
The invention discloses a synthetic method of acetaldehyde alcohol optical active ester. The method comprises the following steps: under the condition of a catalyst solvent, carrying out a reaction on triphosgene andn L-menthol to obtain a reaction product containing L-menthyl chloroformate; adding 1, 4-cis-butenediol into the reaction product obtained in the step 1, adding a proper amount of a catalyst and a proper amount of a solvent, carrying out a reaction to obtain a reaction product containing menthyl dicarbonate, and carrying out post-treatment on the reaction product to obtain purified menthyl dicarbonate; and dissolving the obtained menthyl dicarbonate in a solvent, and introducing ozone to oxidize the menthyl dicarbonate into the acetaldehyde alcohol optical active ester. According to the invention, the conditions of the reaction steps are mild, the operation is simple and convenient, the initial raw materials are cheap and easy to obtain, the reaction steps are short, the generated three-waste pollutants are less, the yield is high, the method is suitable for industrial large-scale production, the reaction steps are simplified to a certain extent, and the subsequent reaction is facilitated.
PROCESS FOR PRODUCING CHLOROFORMATE COMPOUND
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Paragraph 0068; 0069; 0078, (2019/06/20)
The present invention provides a method for safely producing a large amount of chloroformate compound with high yield. The chloroformate compound can be produced by mixing and reacting a solution of triphosgene, an amine and an alcohol compound in a flow reactor. The chloroformate compound can also be produced by mixing and reacting a solution of triphosgene with a solution comprising an amine and an alcohol compound in a flow reactor. The amine is preferably tributylamine, and preferably used in an amount of 0.8 to 3 equivalents relative to an amount of the alcohol compound.
A preparation method of lamivudine
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Paragraph 0042; 0046-0048, (2019/04/02)
The invention discloses a method for preparation of lamivudine. Refined pure 5 S - (cytosine base - 1 ') - 1, 3 - oxathiolane - 2 - ethoxy carbonyl - (1' R, 2'S, 3' R) - menthyl ester; in the weak base and the solvent removed under the condition of chiral L - menthol to get a product of lamivudine. The material of the invention is cheap, the reagents used in the environmental protection, steps is relatively short, mild reaction conditions, atom utilization rate high, high yield, high chemical purity of the obtained product, reach the medical standard, suitable for large-scale production of lamivudine preparation method.
A Suitqable to preparation method
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Paragraph 0042; 0046-0048, (2019/04/02)
The invention discloses a Suitqable to preparation method. Refined pure 5 S - (5 '- fluorocytosine yl - 1') - 1, 3 - oxathiolane - 2 - ethoxy carbonyl - (1 'R, 2'S, 3' R) - menthyl ester; in the weak base and the solvent removed under the condition of chiral L - menthol get products Suitqable to. The invention required the starting raw material is cheap, mild reaction conditions, the atom utilization rate is high, the operation technique is simple, the reagents used in the environmental protection, the resulting high purity, reach the medical standard, is suitable for the industrial production of kindness or gemcitabine.
Safe and Efficient Phosgenation Reactions in a Continuous Flow Reactor
Yasukouchi, Hiroaki,Nishiyama, Akira,Mitsuda, Masaru
supporting information, p. 247 - 251 (2018/02/23)
Phosgene is widely used in organic synthesis owing to its high reactivity, utility, and cost efficiency. However, the use of phosgene in batch processes on the industrial scale is challenging owing to its toxicity. An effective method to minimize reaction volumes and mitigate the safety risks associated with hazardous chemicals is the use of flow reactors. Consequently, we have established a flow reaction system using triphosgene and tributylamine, which affords a homogeneous reaction that avoids clogging issues. In addition, we have demonstrated that this methodology can be applied to a wide variety of phosgene reactions, including the preparation of pharmaceutical intermediates, in good to excellent yields.
Levorotatory meptazinol prodrug as well as preparation method and purpose thereof
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Paragraph 0119; 0121; 0122, (2017/07/19)
The invention provides a levorotatory meptazinol prodrug as well as a preparation method and a purpose thereof, wherein the levorotatory meptazinol prodrug is a compound as shown in a formula I or a stereoisomer, a geometrical isomer, a tautomer, oxynitride, a hydrate, a solvate, a metabolite or a pharmaceutically acceptable salt of the compound as shown in the formula I. The compound is low in hepatic first pass effect and high in bioavailability; a medicine which uses the compound as an active component can be used for treating a neurodegenerative disease or various kinds of acute and chronic pain, such as a wound, postoperative, obstetrical and cancer pain, hemicrania, neuropathic pain and the like.
Variochelins, Lipopeptide Siderophores from Variovorax boronicumulans Discovered by Genome Mining
Kurth, Colette,Schieferdecker, Sebastian,Athanasopoulou, Kalliopi,Seccareccia, Ivana,Nett, Markus
, p. 865 - 872 (2016/05/24)
Photoreactive siderophores have a major impact on the growth of planktonic organisms. To date, these molecules have mainly been reported from marine bacteria, although evidence is now accumulating that some terrestrial bacteria also harbor the biosynthetic potential for their production. In this paper, we describe the genomics-driven discovery and characterization of variochelins, lipopeptide siderophores from the bacterium Variovorax boronicumulans, which thrives in soil and freshwater habitats. Variochelins are different from most other lipopeptide siderophores in that their biosynthesis involves a polyketide synthase. We demonstrate that the ferric iron complex of variochelin A possesses photoreactive properties and present the MS-derived structures of two degradation products that emerge upon light exposure.
