54933-25-4Relevant academic research and scientific papers
Selective Photoinduced Reduction of Nitroarenes to N-Arylhydroxylamines
Kallitsakis, Michael G.,Ioannou, Dimitris I.,Terzidis, Michael A.,Kostakis, George E.,Lykakis, Ioannis N.
, p. 4339 - 4343 (2020)
We report the selective photoinduced reduction of nitroarenes to N-arylhydroxylamines. The present methodology facilitates this transformation in the absence of catalyst or additives and uses only light and methylhydrazine. This noncatalytic photoinduced transformation proceeds with a broad scope, excellent functional-group tolerance, and high yields. The potential of this protocol reflects on the selective and straightforward conversion of two general antibiotics, azomycin and chloramphenicol, to the bioactive hydroxylamine species.
Catalytic Syn-Selective Nitroaldol Approach to Amphenicol Antibiotics: Evolution of a Unified Asymmetric Synthesis of (-)-Chloramphenicol, (-)-Azidamphenicol, (+)-Thiamphenicol, and (+)-Florfenicol
Chen, Fener,Cheng, Dang,Huang, Huashan,Jiang, Meifen,Liu, Minjie,Qu, Hongmin,Xia, Yingqi,Xiong, Tong,Zhang, Yan
, p. 11557 - 11570 (2021/09/02)
A unified strategy for an efficient and high diastereo- and enantioselective synthesis of (-)-chloramphenicol, (-)-azidamphenicol, (+)-thiamphenicol, and (+)-florfenicol based on a key catalytic syn-selective Henry reaction is reported. The stereochemistry of the ligand-enabled copper(II)-catalyzed aryl aldehyde Henry reaction of nitroethanol was first explored to forge a challenging syn-2-amino-1,3-diol structure unit with vicinal stereocenters with excellent stereocontrol. Multistep continuous flow manipulations were carried out to achieve the efficient asymmetric synthesis of this family of amphenicol antibiotics.
Method for continuously preparing chloramphenicol by using micro-reaction system
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Paragraph 0030; 0032-0044, (2021/08/19)
The invention belongs to the technical field of pharmaceutical engineering, and particularly relates to a method for continuously preparing chloramphenicol by using a micro-reaction system. The method comprises the following steps: respectively and simultaneously pumping an organic solution of raw materials (1R, 2R)-2-amino-1-(4-aminophenyl) propane-1, 3-diol and an organic solution of methyl dichloroacetate into a micro-reaction system of a first micro-mixer and a first micro-channel reactor which are communicated with each other, and carrying out continuous amidation reaction; adding acetone, water and a buffer solution into the mixed solution flowing out, and then respectively and simultaneously pumping the mixed solution and the aqueous solution of the potassium hydrogen persulfate composite salt into a micro-reaction system of a second micro-mixer and a second micro-channel reactor which are communicated with each other for continuous oxidation reaction; and finally, carrying out quenching, extraction and other processes to obtain a chloramphenicol product. The method is short in reaction time, convenient to operate, continuous, controllable, free of amplification effect and high in technological process efficiency, the yield of the product chloramphenicol is larger than 90%, and the method has good industrial application prospects.
CmlI is an N-oxygenase in the biosynthesis of chloramphenicol
Lu, Haige,Chanco, Emmanuel,Zhao, Huimin
supporting information; experimental part, p. 7651 - 7654 (2012/09/08)
The N-oxygenation of an amine group is one of the steps in the biosynthesis of the antibiotic chloramphenicol. The non-heme di-iron enzyme CmlI was identified as the enzyme catalyzing this reaction through bioinformatics studies and reconstitution of enzymatic activity. In vitro reconstitution was achieved using phenazine methosulfate and NADH as electron mediators, while in vivo activity was demonstrated in Escherichia coli using two substrates. Kinetic analysis showed a biphasic behavior of the enzyme. Oxidized hydroxylamine and nitroso compounds in the reaction were detected both in vitro and in vivo based on LC-MS. The active site metal was confirmed to be iron based on a ferrozine assay. These findings provide new insights into the biosynthesis of chloramphenicol and could lead to further development of CmlI as a useful biocatalyst.
