22687-06-5Relevant academic research and scientific papers
A green synthesis of nitrones in glycerol
Shariatipour, Monire,Jadidinejad, Masoumeh,Heydari, Akbar
, (2019/11/11)
Abstract: An eco-friendly and efficient synthesis of nitrones is presented by condensation of an equimolar amount of aldehydes and N-substituted hydroxylamine hydrochlorides in glycerol as a recyclable solvent-catalyst. This novel protocol provides rapid and mild access to a series of nitrone derivatives in good to excellent yields in the absence of catalyst and base. Graphic abstract: SYNOPSIS In this study, a base-free protocol by using glycerol as the solvent-catalyst was applied for an eco-friendly synthesis of nitrones from the condensation of aldehydes and N-substituted hydroxylaminehydrochlorides.[Figure not available: see fulltext.].
α,β-Unsaturated Amides as Dipolarophiles: Catalytic Asymmetric exo-Selective 1,3-Dipolar Cycloaddition with Nitrones
Zhang, Ming,Kumagai, Naoya,Shibasaki, Masakatsu
supporting information, p. 12450 - 12455 (2017/09/18)
1,3-Dipolar cycloaddition is a commonly exploited method to access 5-membered chemical entities with a variety of peripheral functionalities and their stereochemical arrangements. Nitrones are isolable 1,3-dipoles that exhibit sufficient reactivity toward electron-deficient olefins in the presence of Lewis acids to deliver highly substituted isoxazolidines. Herein we document that α,β-unsaturated amides, generally regarded as barely reactive in a 1,3-dipolar reaction manifold, were effectively activated using the designed 7-azaindoline auxiliary in an In(OTf)3/bishydroxamic acid catalytic system. The broad substrate scope and clean removal of the 7-azaindoline auxiliary from the product highlight the synthetic utility of the present catalysis.
Synthesis and cytotoxic evaluation of novel platinum(II) complexes with C2-asymmetric and C2-symmetric chiral vicinal diamines
Zhang, Chen,Liu, Hongrui,Yang, Qing,Chang, Jun,Sun, Xun
, p. 154 - 158 (2013/08/24)
A series of new platinum(II) complexes with C2-asymmetric and C2-symmetric 1,2-diamines were designed and synthesized by convenient methods, involving samarium diiodide induced reductive coupling as the key step. The results of cytotoxicity showed that compounds (R,R)-11a and (S,S)-11a, two novel platinum(II) complexes with asymmetric 1,2-diamines, exhibited more potent cytotoxicity than that of oxaliplatin against all leukemia cell lines. Interestingly, (R,R)-11a and (S,S)-11a demonstrated less potent activity against three solid cancer cell lines than that of oxaliplatin, which indicated that these two compounds may only selectively inhibit the leukemia cell lines. In contrast, (R,R)-15a and (S,S)-15a, two platinum(II) complexes with symmetric 1,2-diamines, showed similar cytotoxicity to that of oxaliplatin against all leukemia cell lines and more potent activity against solid cancer cell lines. Further flow cytometry data indicated that (R,R)-11a could obviously arrest leukemia K562 cells in G2/M phases. A series of new platinum(II) complexes with C2-asymmetric and C2-symmetric 1,2-diamines were designed and synthesized by convenient methods, involving samarium diiodide induced reductive coupling as the key step. The cytotoxicity of these analogs against four leukemia and three solid cancer cell lines was evaluated and the preliminary structure-activity relationship is also discussed. Flow cytometry data indicated that (R,R)-11a could obviously arrest leukemia K562 cells in G2/M phases. Copyright
Indium (Zinc)-copper-mediated barbier-type alkylation reaction of nitrones in water: Synthesis of amines and hydroxylamines
Yang, Yong-Sheng,Shen, Zhi-Liang,Loh, Teck-Peng
supporting information; experimental part, p. 1209 - 1212 (2009/08/07)
An efficient method for the Barbier-type alkylation reaction of various nitrones (including chiral version) and alkyl halides in water is described. The amines and hydroxylamines can be obtained in good yields, depending on the judicious choice of the metal complexes used.
Enantioselective nitrone cycloadditions of α,β-unsaturated 2-acyl imidazoles catalyzed by bis(oxazolinyl)pyridine-cerium(IV) triflate complexes
Evans, David A.,Song, Hyun-Ji,Fandrick, Keith R.
, p. 3351 - 3354 (2007/10/03)
Enantioselective nitrone cycloadditions with β-substituted α,β-unsaturated 2-acyl imidazoles catalyzed by bis(oxazolinyl) pyridine-cerium(IV) triflate complexes 1 have been reported. The isoxazolidine products were efficiently transformed into densely functionalized β′-hydroxy-β-amino acid derivatives.
Reduction of 2,3-dihydroisoxazoles to β-amino ketones and β-amino alcohols
Aschwanden, Patrick,Kvaerno, Lisbet,Geisser, Roger W.,Kleinbeck, Florian,Carreira, Erick M.
, p. 5741 - 5742 (2007/10/03)
(Chemical Equation Presented) We report the reduction of 2,3-dihydroisoxazoles to β-amino ketones and β-amino alcohols. The latter are obtained in high diastereoselectivity with preference for the syn isomer.
