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Environmental Impact Metrics
Published in John Andraos, Synthesis Green Metrics, 2018
Determine the acids produced when the following compounds decompose in water. Acetic anhydrideChlorineMethyl chloroformateCarbon dioxideDiphosgenePhosphorus oxychloridePhosgeneSulfur dioxideSulfur trioxideTriphosgene
Macrocyclic Receptors Synthesis, History, Binding Mechanism: An Update on Current Status
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
Peyrard et al. introduced -extended electron-withdrawing moieties such as COOH moiety at the ortho position of methoxy group attached directly to the cyclotriveratrylene core structure (Peyrard et al. 2012). The reaction proceeded through a lithiation reaction (Scheme 44), with ethyl chloroformate and finally, hydrolysis of ester group to provide carboxylic acid-based cyclotriveratrylene receptor 72 in 54% yield.
Arsenals of Pharmacotherapeutically Active Proteins and Peptides: Old Wine in a New Bottle
Published in Debarshi Kar Mahapatra, Swati Gokul Talele, Tatiana G. Volova, A. K. Haghi, Biologically Active Natural Products, 2020
Acylation: In the process of acylation, the amino acids are subjected to reaction with acid chlorides or acid anhydrides in presence of alkaline medium [1]. Acylation helps in protecting the amino group form nucleophilic substitution reaction. Amino acids are protected during peptide synthesis by acylation with benzyl chloroformate by formation of benzyloxycarbonyl derivative [100].
An insight on the different synthetic routes for the facile synthesis of O/S-donor carbamide/thiocarbamide analogs and their miscellaneous pharmacodynamic applications
Published in Journal of Sulfur Chemistry, 2023
Faiza Asghar, Bushra Shakoor, Babar Murtaza, Ian S. Butler
Researchers next looked into the breadth of Zr(IV)-catalyzed carbonate-carbamate after they had effective circumstances. In general, reactions were carried out in the presence of 5 mol % Zr(Ot-Bu)4 and 10 mol % HYP at 80°C with 1.0 equivalent amine and 1.5 equivalent dialkyl carbonate for 12 h. In reactions with benzylamine, four distinct carbonates (Me, Et, Bn, and Allyl) indicated similar reactivity. Chemoselectivity for aliphatic vs. aromatic amines was revealed in the reaction of 2-aminobenzylamine with dimethylcarbonate. On the other hand, 2-aminobenzylamine has been observed to react with methyl chloroformate to yield the equivalent biscarbamate without selectivity. Under the reaction circumstances, functional groups such as acetonide, indole, and cyclic ketal were shown to be endured. Cyclic urea products were not found in diamine substrates [34].
Self-assembly of a cholesteryl-derived diphenylalanine in ethylenediamine-water mixed medium
Published in Journal of Dispersion Science and Technology, 2021
Juntan Zhou, Jingxuan Yang, Li Zhao, Ce Wang, Baocai Xu
In this work, a cholesteryl-tailed FF molecule at the N-terminus was designed and synthesized (Chol-FF) (Scheme 1). The carboxyl group was first protected by esterification. Upon the reaction between the amine group of FF and acyl chloride of cholesteryl chloroformate, Chol-FF was obtained after a hydrolysis reaction. The amphiphilic Chol-FF was dissolved in ethylenediamine (EDA)/water mixed solvents, and emulsions formed, which may be primarily ascribed to the delicate hydrophilic-hydrophobic balance of Chol-FF. Upon shaking, the emulsion droplets broke up and one-dimensional micron-sized fibers were formed in EDA/water (9-1, v/v) system. A lamellar molecular packing mode was verified driven mainly by three forces, i.e., intermolecular π-π stacking, hydrogen bonding, and van der Waals forces.
Self-assembling behaviour of new functional photosensitive cinnamoyl-based reactive mesogens
Published in Liquid Crystals, 2020
Alexej Bubnov, Martin Cigl, Nela Sedláčková, Damian Pociecha, Zuzana Böhmová, Věra Hamplová
4-hydroxybezoic acid (27.60 g, 0.20 mol) was dissolved in a mixture of sodium hydroxide (20.0 g, 0.50 mol) and water (300 ml) and cooled to 0°C. Then, methyl chloroformate (28.30 g, 0.30 mol) was added dropwise with stirring, keeping the temperature at 0°C. The reaction mixture was then stirred for ca. 2 h while a white precipitate was gradually formed. Resulting mixture was acidified by a small amount of hydrochloric acid (pH 4–5) and white solid was filtered off and washed with cold water. After drying, the solid was recrystallised from ethanol and dried under vacuum. Obtained 4-(methoxycarbonyloxy)benzoic acid was suspended in thionyl chloride (40 ml) and a catalytic amount of DMF was added. The reaction mixture was refluxed for 2 h. The excess of thionyl chloride was distilled off. Oily residue was diluted with toluene and the solvent removed on rotatory evaporator. Obtained benzoyl chloride 11 was used in the next synthetic step without further purification. 1H NMR (CDCl3): 8.18 (2H, d, J = 8.8, H-2, H-6), 7.37 (2H, d, J = 8.8, H-3, H-5), 3.96, (3H, s, OCH3).