88-99-3Relevant articles and documents
Method for treating 4-AA intermediate waste liquid
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, (2022/03/17)
The invention belongs to the technical field of chemical synthesis, and discloses a method for treating 4-AA intermediate waste liquid. The method comprises the following three steps of: (1) heating N, N-bis (2-ethoxyl) phthalimide and a basic catalyst in an aqueous solution for reflux reaction to prepare a sodium phthalate feed liquid; (2) carrying out reduced pressure distillation on the sodium phthalate feed liquid in the step (1) to obtain ethanolamine, and preparing phthalic acid from residual residues through acid regulation; and (3) introducing ammonia gas or adding ammonia water into a reaction kettle containing the phthalic acid so as to perform heating reaction, performing cooling after the reaction is finished, adding water for washing, crystallizing, filtering and drying to obtain the phthalimide. According to the method disclosed by the invention, the byproduct hazardous wastes in the deprotection step of the enzymic method 4-AA are converted into the initial raw material of the enzymic method 4-AA, so that the hazardous wastes are turned into wealth, the raw material cost is effectively reduced, the storage, transportation and treatment expenses of the hazardous wastes are also effectively reduced, and the method has remarkable economic benefits and environmental benefits.
A visible light driven 3D hierarchical CoTiO3/BiOBr direct Z-scheme heterostructure with enhanced photocatalytic degradation performance
He, Shiwu,Li, Qiang,Lu, Xiaoxiao,Tian, Zhenfei,Wang, Lijie,Zhang, Jinfeng
, p. 124 - 135 (2021/12/30)
A series of novel three-dimensional (3D) CoTiO3/BiOBr (CTBB) hierarchical heterostructures were preparedviaa simple hydrothermal method. In comparison with pure CoTiO3and BiOBr, all the CTBB nanocomposites display enhanced photocatalytic performance toward dye decomposition. Particularly, CTBB-5 reveals the best photocatalytic efficiency for RhB removal with aKof 0.2030 min?1, which is about 50.75 and 3.02-fold higher than that of pure CoTiO3and BiOBr, respectively. The outstanding activity is further demonstrated by MO photodegradation. The dramatically enhanced activity can be attributed to the increased surface area and reduced recombination probability of charge carriers. Furthermore, CTBB-5 exhibits excellent stability after repetitively running four times. The h+and ˙O2?are identified as the dominating reactive species contributing to the oxidation reaction. Finally, a possible Z-scheme charge transfer mechanism is presented and analyzed in detail.
Chemical Modifications Induced by Phthalic Anhydride, a Respiratory Sensitizer, in Reconstructed Human Epidermis: A Combined HRMAS NMR and LC-MS/MS Proteomic Approach
Khong, Minh-Thuong,Berl, Valérie,Kuhn, Lauriane,Hammann, Philippe,Lepoittevin, Jean-Pierre
, p. 2087 - 2099 (2021/08/30)
Chemical skin and respiratory allergies are becoming a major health problem. To date our knowledge on the process of protein haptenation is still limited and mainly derived from studies performed in solution using model nucleophiles. In order to better understand chemical interactions between chemical allergens and the skin, we have investigated the reactivity of phthalic anhydride 1 (PA), a chemical respiratory sensitizer, toward reconstructed human epidermis (RHE). This study was performed using a new approach combining HRMAS NMR to investigate the in situ chemical reactivity and LC-MS/MS to identify modified epidermal proteins. In RHE, the reaction of PA appeared to be quite fast and the major product formed was phthalic acid. Two amide type adducts on lysine residues were observed and after 8h of incubation, we also observed the formation of an imide type cyclized adducts with lysine. In parallel, RHE samples topically exposed to phthalic anhydride (13C)-1 were analyzed using the shotgun proteomics method. Thus, 948 different proteins were extracted and identified, 135 of which being modified by PA, i.e., 14.2% of the extracted proteome. A total of 211 amino acids were modified by PA and validated by fragmentation spectra. We thus identified 154 modified lysines, 22 modified histidines, 30 modified tyrosines, and 5 modified arginines. The rate of modified residues, as a proportion of the total number of modifiable nucleophilic residues in RHE, was rather low (1%). At the protein level, modified proteins were mainly type I and type II keratins and other proteins which are abundant in the epidermis such as protein S100A, Caspase 14, annexin A2, serpin B3, fatty-acid binding protein 5, histone H2, H3, H4, etc. However, the most modified protein, mainly on histidine residues, was filaggrin, a protein that is of low abundance (0.0266 mol %) and rich in histidine.