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1.
S. R. Jayapradha S. Muthusubramanian 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):32-38
Abstract The synthesis of a new set of 2,3,4,5-substituted isoxazolidines having a sulfur containing heterocyclic moiety has been described. The structural features of the compounds have been analyzed by 1H and 13C NMR spectroscopy as well as by single crystal X-ray studies. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: .cif file.] 相似文献
2.
An environmentally friendly process is reported for the palladium(II)‐catalyzed cyclofunctionalization of allylic hydroxylamine derivatives using a catalytic amount of copper(II) acetate and molecular oxygen as the cooxidant. 相似文献
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4.
Gagandeep Singh Naman Gupta Vivek Gupta Mohan Paul Singh Ishar 《Tetrahedron letters》2017,58(25):2456-2459
Reductive ring opening of isoxazolidine moiety of chromano–piperidine-fused isoxazolidines (3a–c) with HCOONH4 and 10% Pd/C in a mixture of solvents (THF/MeOH) at ambient temperature, affords novel 2-(methylamino)-4-oxo-N-phenyl-N-propyl-4H-chromene-3-carboxamide (4), which is apparently derived from reductive NO bond cleavage followed by tandem intramolecular rearrangements. Plausible mechanistic rationale for the formation of compound 4 is proffered. 相似文献
5.
《Journal of heterocyclic chemistry》2017,54(1):80-88
1,3‐Dipolar cycloaddition reactions of N‐cyclohexyl maleimide ( 1 ) with azomethine N‐oxide ( 2 ) have afforded novel isoxazolidine ( 3 ) in excellent yield. Their structures have been characterized from their IR, 1H‐NMR, 13C‐NMR, 1H,1H‐COSY, MS(ESI), and elemental analysis techniques. In vitro antibacterial activity of the synthesized compounds were investigated against a representative panel of pathogenic strains specifically two Gram‐positive bacteria (Staphylococcus aureus and Streptococcus pyogenes ) and two Gram‐negative bacteria (Pseudomonas aeruginosa and Escherichia coli ) using agar‐well diffusion assay. Some of the compounds ( 3a , 3k , 3n , and 3o ) exhibited promising antibacterial activities. All the synthesized compounds have also been screened for their antioxidant activities and were found to be significantly active. 相似文献
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Crystal structure of two brom containing aza-tetracyclic fused N-heterocycles including isoxazolidine ring compounds have been determined in single-crystal X-ray diffraction studies. The compound, C14H19BrN2O3, (1), and C12H15BrN2O3, (2), were obtained from a stereospecific[3+2] 1,3-cycloaddition of oxime based tandem nitrone generation reactions. The envelope conformation of the isoxazolidine rings are different, leading the substituents to be pseudoaxial in (1) and pseudoequatorial in (2). The stereochemistry of these fused compounds are exo- and endo-stereoisomer geometry contributed by exo and endo transition state of nitrone 1,3-dipolar cycloaddition reactions. The title compound (1) crystallizes in the monoclinic space group P2
1/n with a = 12.6221(5)Å, b = 7.5917(4) Å, c = 16.2350(9) Å, = 112.254(5)°, V = 1439.81(12) Å3, and D
calc = 1.583 Mg/m3 for Z = 4 and compound (2) crystallizes in the monoclinic space group P2
1/c with a = 11.6906(9) Å, b = 6.4255(7) Å, c = 17.2070(10) Å, = 109.264(5)°, V = 1220.2(2) Å3, and D
calc = 1.716 Mg/m3 for Z = 4. The antibacterial activity of both compounds were investigated for three Gram (+) and two Gram (–) bacteria by employing broth microdilution method and subsequently inhibitory activity against yeast-like fungi was also determined. 相似文献
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A high pressure mediated (3+2) cycloaddition polymerization strategy has been employed to afford linear poly(isoxazolidine) architectures. Under these high pressure conditions this cycloaddition process was found to afford primarily endo-heterocycles which when translated to the polymerization should ultimately affect the tacticity and resultant properties of the polymer. The stereoselectivity occurred as a result of a lower volume of activation for the endo-transition state and the application of a ‘type-I’ regime (HOMODipole-LUMODipolarophile) cycloaddition process that features secondary orbital interactions within the extended molecular orbitals. A variety of linker segments were employed in an attempt to affect the physical properties of the polymeric cycloadducts such as Tg and solubility in order to tailor these materials for use in coating applications. 相似文献
8.
《Journal of carbohydrate chemistry》2013,32(6):501-511
Synthesis of C-linked isoxazolidines was achieved by addition of nitrone to C-linked sugar butenolides, which in turn were prepared by iodolactonisation on the chiral template derived from diacetone glucose. 相似文献
9.
Microwave‐assisted stereoselective 1,3‐dipolar cycloaddition of C,N‐diarylnitrones (i.e., N‐(arylmethylidene)benzenamine N‐oxides) 2 to substituted bis(arylmethylidene)acetones (=1,5‐diarylpenta‐1,4‐dien‐3‐ones) 1 leading to diastereoisomer pairs of bis‐isoxazolidines 3 and 4 in good to excellent yield is described (Scheme 2 and Table 2). The configuration outcome of the reaction is discussed based on the NMR and X‐ray data of the products. 相似文献
10.
YUKSEKTEPE cigdem OZKAN Hamdi YAVUZ Serkan YANMAZ Volkan DiSLI Ali BUYUKGUNGOR Orhan 《结构化学》2012,31(9):1251-1262
The compound of dimethyl trans-3-(2-bromophenyl)-2-methylisoxazolidine-4,5-dicarboxylate has been synthesized and characterized by IR, 1H-NMR, 13C-NMR, 2D-NMR (COSY, NOESY, HMQC, HMBC) and UV-vis. spectroscopy techniques and single-crystal X-ray diffraction (XRD). The biological activities of the title compound have been investigated in detail. The new compound crystallizes in monoclinic, space group C2/c with a = 26.9263(10), b = 7.0970(2), c = 19.8554(7) ?, and β = 126.630(2). In addition to the single crystal structure, the molecular geometry, vibrational frequencies, chemical shifts, molecular electrostatic potential and frontier molecular orbital analysis of the title compound in the ground state have been calculated by Density Functional Theory (DFT) method. 相似文献