70746-04-2Relevant academic research and scientific papers
Efficient Synthesis of Benzothiazinone Analogues with Activity against Intracellular Mycobacterium tuberculosis
Richter, Adrian,Narula, Gagandeep,Rudolph, Ines,Seidel, Rüdiger W.,Wagner, Christoph,Av-Gay, Yossef,Imming, Peter
supporting information, (2021/12/27)
8-Nitrobenzothiazinones (BTZs) are a promising class of antimycobacterial agents currently under investigation in clinical trials. Starting from thiourea derivatives, a new synthetic pathway to BTZs was established. It allows the formation of the thiazinone ring system in one synthetic step and is applicable for preparation of a wide variety of BTZ analogues. The synthetic procedure furthermore facilitates the replacement of the sulphur atom in the thiazinone ring system by oxygen or nitrogen to afford the analogous benzoxazinone and quinazolinone systems. 36 BTZ analogues were prepared and tested in luminescence-based assays for in vitro activity against Mycobacterium tuberculosis (Mtb) using the microdilution broth method and a high-throughput macrophage infection assay.
Ammonium Chloride-Promoted Rapid Synthesis of Monosubstituted Ureas under Microwave Irradiation
Lan, Chunling Blue,Auclair, Karine
supporting information, p. 5135 - 5146 (2021/10/19)
Monosubstituted ureas are important scaffolds in organic chemistry. They appear in various biologically active compounds and serve as versatile precursors in synthesis. Monosubstituted ureas were originally prepared using toxic and hazardous phosgene equivalents. Modern methods include transamidation of urea and nucleophilic addition to cyanate salts, both of which suffer from a narrow substrate scope due to the need for a strong acid and prolonged reaction times. We hereby report that ammonium chloride can promote the reaction between amines and potassium cyanate to generate monosubstituted ureas in water. This method proceeds rapidly under microwave irradiation and tolerates a broad range of functional groups. Unlike previous strategies, it is compatible with other nucleophiles, acid-labile moieties, and most of the common protecting groups. The products precipitate out of solution, allowing facile isolation without column chromatography.
Regioselective Formal [3+2] Cycloadditions of Urea Substrates with Activated and Unactivated Olefins for Intermolecular Olefin Aminooxygenation
Wu, Fan,Alom, Nur-E,Ariyarathna, Jeewani P.,Na?, Johannes,Li, Wei
supporting information, p. 11676 - 11680 (2019/07/31)
A new class of intermolecular olefin aminooxygenation reaction is described. This reaction utilizes the classic halonium intermediate as a regio- and stereochemical template to accomplish the selective oxyamination of both activated and unactivated alkenes. Notably, urea chemical feedstock can be directly introduced as the N and O source and a simple iodide salt can be utilized as the catalyst. This formal [3+2] cycloaddition process provides a highly modular entry to a range of useful heterocyclic products with excellent selectivity and functional-group tolerance.
Some Extensions of von Braun (BrCN) Reaction on Organic Bases, Part IV
Siddiqui, Salimuzzaman,Haider, S. Imtiaz,Ahmad, S. Salman,Siddiqui, B. Shaheen
, p. 546 - 549 (2007/10/02)
Extensions of von Braun cyanogen bromide reaction have been undertaken on some aliphatic and heterocyclic amines.Monocyanamides of all these bases yielded their respective urea and carboxamide derivatives on hydrolysis with dilute hydrochloric acid.They also gave the amido derivatives on reaction with Zn/HCl, as in the case of diisobutyl and di-2-butyl cyanamides. - Key words: von Braun Cyanogen Bromide Reaction
