10507-69-4Relevant articles and documents
Photoorganocatalytic One-Pot Synthesis of Hydroxamic Acids from Aldehydes
Papadopoulos, Giorgos N.,Kokotos, Christoforos G.
, p. 6964 - 6967 (2016)
An efficient one-pot synthesis of hydroxamic acids from aldehydes and hydroxylamine is described. A fast, visible-light-mediated metal-free hydroacylation of dialkyl azodicarboxylates was used to develop the subsequent addition of hydroxylamine hydrochloride. A range of aliphatic and aromatic aldehydes were employed in this reaction to give hydroxamic acids in high to excellent yields. Application of the current methodology was demonstrated in the synthesis of the anticancer medicine vorinostat.
Alternating Current Electrolysis as Efficient Tool for the Direct Electrochemical Oxidation of Hydroxamic Acids for Acyl Nitroso Diels–Alder Reactions
F?hrmann, Jan,Hilt, Gerhard
, p. 20313 - 20317 (2021)
The acyl nitroso Diels–Alder reaction of 1,3-dienes with electrochemically oxidised hydroxamic acids is described. By using alternating current electrolysis, their typical electro-induced decomposition could be suppressed in favour of the 1,2-oxazine cycloaddition products. The reaction was optimised using Design of Experiments (DoE) and a sensitivity test was conducted. A mixture of triethylamine/hexafluoroisopropanol served as supporting electrolyte in dichloromethane, thus giving products of high purity after evaporation of the volatiles without further purification. The optimised reaction conditions were applied to various 1,3-dienes and hydroxamic acids, giving up to 96 % isolated yield.
Straightforward synthesis of 4,5-bifunctionalized 1,2-oxazinanes via Lewis acid promoted regio- and stereo-selective nucleophilic ring-opening of 3,6-dihydro-1,2-oxazine oxides
Huang, Xiu-Rong,Zhang, Yu-Mei,Wan, Ting-Biao,Zhang, Piao,Zhang, Xiu-Xiu,Wang, Fang-Ming,Xu, Defeng,Shen, Mei-Hua,Xu, Hua-Dong
, (2019)
Functionalized 1,2-oxazinanes are interesting and valuable heterocycles with potential applications in synthetic and medicinal chemistry. A straightforward strategy for quick access to unprecedented trans-4-hydroxyl-5-azido/cyano/amino 1,2-oxazinanes are developed: N-COR 3,6-dihydro- 1,2-oxazine oxides are prepared with ease from related dihydro- 1,2-oxazines and opened by nucleophiles TMSN3, TMSCN and aryl/alkyl amines. Appropriate Lewis acid catalysts are found playing a vital role for both reaction rate and regioselectivity. The N-COR group can be removed under mild conditions to provide highly desirable NH 1,2-oxazinanes inaccessible via previous methods.
Carbonic anhydrase inhibitors. Inhibition of the β-class enzymes from the fungal pathogens Candida albicans and Cryptococcus neoformans with branched aliphatic/aromatic carboxylates and their derivatives
Carta, Fabrizio,Innocenti, Alessio,Hall, Rebecca A.,Mühlschlegel, Fritz A.,Scozzafava, Andrea,Supuran, Claudiu T.
, p. 2521 - 2526 (2011)
The inhibition of the β-carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic fungi Cryptococcus neoformans (Can2) and Candida albicans (Nce103) with a series of 25 branched aliphatic and aromatic carboxylates has been investigated. Human isoforms hCA I and II were also included in the study for comparison. Aliphatic carboxylates were generally millimolar hCA I and II inhibitors and low micromolar/submicromolar β-CA inhibitors. Aromatic carboxylates were micromolar inhibitors of the four enzymes but some of them showed low nanomolar activity against the fungal pathogenic enzymes. 4-Hydroxy- and 4-methoxy-benzoate inhibited Can2 with KIs of 9.5-9.9 nM. The methyl esters, hydroxamates, hydrazides and carboxamides of some of these derivatives were also effective inhibitors of the α- and β-CAs investigated here.
P(III)-Assisted Electrochemical Access to Ureas via in situ Generation of Isocyanates from Hydroxamic Acids
Meng, Haiwen,Sun, Kunhui,Xu, Zhimin,Tian, Lifang,Wang, Yahui
supporting information, p. 1768 - 1772 (2021/03/26)
An external oxidant-free protocol for the generation of isocyanates from hydroxamic acids assisted by trivalent phosphine under mild electrochemical conditions was reported. The process started with the anodic oxidation of hydroxamic acids, followed by reacting with phosphine to form corresponding alkoxyphosphoniums and subsequent rearrangement with the release of tri-substituted phosphine oxide as the driving force to give isocyanates, which were trapped by N-based nucleophiles to produce various ureas. This method provides a broadly applicable procedure to access isocyanate intermediates under mild electrochemical conditions.
Palladium-Catalyzed 5-exo-dig Cyclization Cascade, Sequential Amination/Etherification for Stereoselective Construction of 3-Methyleneindolinones
Zuo, Youpeng,He, Xinwei,Tang, Qiang,Hu, Wangcheng,Zhou, Tongtong,Hu, Wenbo,Shang, Yongjia
, p. 2117 - 2123 (2020/12/22)
An cascade intramolecular 5-exo-dig cyclization of N-(2-iodophenyl)propiolamides and sequential amination/etherification (with N-hydroxybenzamides, phenyl hydroxycarbamate) protocol for the synthesis of amino- and phenoxy-substituted 3-methyleneindolinones using unexpensive Pd(PPh3)4 as catalyst has been developed. The protocol enables the assembly of structurally important oxindole cores featuring moderate functional group tolerance (particularly the halo group), affording a broad spectrum of products with diverse substituents in good to excellent yields. (Figure presented.).
