951-82-6Relevant articles and documents
One-Pot Biocatalytic In Vivo Methylation-Hydroamination of Bioderived Lignin Monomers to Generate a Key Precursor to L-DOPA
Birmingham, William R.,Galman, James L.,Parmeggiani, Fabio,Seibt, Lisa,Turner, Nicholas J.
, (2022/01/13)
Electron-rich phenolic substrates can be derived from the depolymerisation of lignin feedstocks. Direct biotransformations of the hydroxycinnamic acid monomers obtained can be exploited to produce high-value chemicals, such as α-amino acids, however the reaction is often hampered by the chemical autooxidation in alkaline or harsh reaction media. Regioselective O-methyltransferases (OMTs) are ubiquitous enzymes in natural secondary metabolic pathways utilising an expensive co-substrate S-adenosyl-l-methionine (SAM) as the methylating reagent altering the physicochemical properties of the hydroxycinnamic acids. In this study, we engineered an OMT to accept a variety of electron-rich phenolic substrates, modified a commercial E. coli strain BL21 (DE3) to regenerate SAM in vivo, and combined it with an engineered ammonia lyase to partake in a one-pot, two whole cell enzyme cascade to produce the l-DOPA precursor l-veratrylglycine from lignin-derived ferulic acid.
Preparation method of 3,4,5-triethoxy phenylacetic acid
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Paragraph 0011; 0012; 0015, (2017/12/30)
The invention relates to a preparation method of 3,4,5-triethoxy phenylacetic acid. The preparation method is characterized by comprising the following steps: mixing a preheated 3,4,5-triethoxy benzaldehyde, a phase transfer catalyst, chloroform and a preheated alkaline solution into a channel reactor for reaction, adjusting the pH value of a water phase of reaction liquid by virtue of concentrated hydrochloric acid, and cooling for crystallization, so as to obtain 3,4,5-triethoxy mandelic acid or salt; adding 3,4,5-triethoxy mandelic acid or salt and sodium iodide into a polar aprotic solvent, preheating, and inputting the mixture and trimethylchlorosilane into a tubular reactor, so as to obtain a reaction solution; mixing the reaction solution with organic acid, mixing zinc powder with the polar aprotic solvent, and introducing the two mixtures into the channel reactor for reaction so as to obtain reaction liquid; and cooling the reaction liquid for crystallization, filtering, washing a filter cake, combining filtrate, washing, evaporating to obtain a solvent, and carrying out vacuum drying, so as to obtain 3,4,5-triethoxy phenylacetic acid. The preparation method has the advantages that the safety is high, the pollution is low, the cost is low, the yield is high, and the continuous production can be realized.
Synthesis of salidroside analogues and their ability of DPPH radical scavenging activity
Zheng, Cheng,Guo, Yibing,Meng, Ying,Dou, Sufeng,Shao, Jian,Yang, Yumin
, p. 654 - 664 (2013/07/11)
Salidroside is a phenylpropanoid glycoside isolated from Rhodiolarosea L., a traditional Chinese medicinal plant, and has displayed a broad spectrum of pharmacological properties. In this paper, about 22 novel glycosides have been synthesized and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenge activity of each glycoside has been evaluated. 2-(3,4,5-Trihydroxyphenyl)ethyl β-D-galactopyranoside and 3-(3,4,5-trihydroxyphenyl)propyl β-D-glucopyranoside exhibit significant activity prior to salidroside and Vitamin C with EC50 values of 35.85 μM and 36.71 μM, respectively. The results indicate that the phenolic hydroxyl group of these compounds is important for radical scavenging activity and phenyl ring substitution by electron-donating substituents lead to increased antioxidant activity.
