排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
A mild,chemoselective oxidation of sulfides to sulfoxides using o-iodoxybenzoic acid and tetraethylammonium bromide as catalyst 总被引:2,自引:0,他引:2
A mild, selective, and high-yielding method for oxidation of sulfides to sulfoxides using IBX and tetraethylammonium bromide in a variety of solvents is described. The method offers the advantage of short reaction times, no over-oxidation to sulfones, and compatibility to a wide range of functional groups. 相似文献
2.
The x-ray diffraction intensities of Bragg reflections have been measured at room temperature for thulium selenide, samarium sulphide, samarium selenide and samarium telluride. On the basis of a common amplitude approximation, the Debye-Waller factor, the mean amplitude of vibration and the Debye temperature have been evaluated. The values of the Debye temperatures and mean amplitudes of vibration are 176±16°K, 0·185 ± 0·017 Å (TmSe), 155 ± 7°K, 0·244 ± 0·012 Å (SmS), 153 ± 14°K, 0·221 ± 0·020 Å (SmSe) and 151 ± 20°K, 0·204 ± 0·027 Å (SmTe). 相似文献
3.
Swapnil S. DeshmukhSameerana N. Huddar Ravindra R. JadhavKrishnacharya G. Akamanchi 《Tetrahedron letters》2011,52(35):4533-4536
Oxiranes undergo oxidative fragmentation when treated with hypervalent iodine(V) reagents particularly o-iodoxybenzoic acid in aqueous ammonia to give nitriles. The reaction goes via the formation of 1, 2-amino alcohols as intermediates followed by C-C bond cleavage. 相似文献
4.
位于藏东南的帕隆藏布流域,处在东喜马拉雅构造结的北缘,是新构造强烈隆升区,断层、褶皱等地质构造发育。在青藏高原隆升及气候变化等内外动力作用下,研究区内堆积体分布广泛,具有独特的工程地质特征并成为该区内地质灾害的主要物源。由于河流的下切及川藏公路的修建,形成了许多高陡的堆积体边坡,以冰碛边坡最为典型。由于其特殊的物源特征及形成过程,冰碛物具有粒度分布范围广、粗粒含量多等与其他沉积物不同的粒度特征。冰碛物粒度分布范围广的特征,导致随着研究尺度的不同,其结构特征也不相同,具有明显的尺度效应。冰碛土的力学强度一般强于其他堆积体,但受不同粒径颗粒的含量及分布、形成时代的影响,其力学特征也有所差异。作者对川藏公路沿线部分典型的剖面进行了量测,所量测的剖面虽然只是整个斜坡的一部分,与经验数据相比,仍表现出高陡的特征,而且很多边坡在既高且陡的形态下仍能保持稳定。本文以极限平衡理论为基础,采用多种方法对这类边坡的稳定性进行计算分析,求出边坡的安全系数。考虑各种地震烈度下边坡的稳定性,得出这些边坡的安全系数与地震加速度具有严格的指数相关关系。 相似文献
5.
Pravin C. Patil Dinesh S. Bhalerao Prasad S. Dangate Krishnacharya G. Akamanchi 《Tetrahedron letters》2009,50(42):5820-5822
Thioamides undergo oxidative dimerization on treatment with hypervalent iodine(V)-containing reagents, particularly o-iodoxybenzoic acid (IBX), in the presence of tetraethylammonium bromide (TEAB) to generate 3,5-disubstituted 1,2,4-thiadiazoles in excellent yield. 相似文献
6.
2,4‐Dinitroimidazole (2,4‐DNI), an important starting material for nitroimidazooxazole and nitroimidazooxazine types of antitubercular agents was synthesized by rearrangement of 1,4‐dinitroimidazole (1,4‐DNI) under microwave irradiation. Various new nitroimidazooxazoles analogues were prepared using 2,4‐DNI and were tested preliminarily against Mycobacterium tuberculosis, H37Rv strain. Some were found to be active. 相似文献
7.
Sulfated tungstate catalyzed environmentally benign, simple, one pot, and solvent-free method has been developed for the synthesis of 1,3,5-triarylbenzenes via cyclic self-condensation of three molecules of aryl ketones. High yields, short reaction time, easy work-up procedure and recycling of the catalyst endorse advantage. 相似文献
8.
Zubair M. Abdulla Radhakrishnan P. Iyer Krishnamachari G. Akamanchi Mariam S. Degani Evans C. Coutinho 《Journal of heterocyclic chemistry》2011,48(1):38-49
Open‐chain bis‐Reissert compounds 1 were converted to the corresponding bis‐oxazolium intermediates via acid‐catalyzed intramolecular cyclization. These oxazolium compounds exist in a variety of tautomeric structures in which the meso‐ionic form can be intercepted by reaction with dipolarophiles in a 1,3‐dipolar‐cycloaddition reaction to produce a variety of highly functionalized bis‐pyrrole esters 2 . In turn, the bis‐pyrrole esters could be converted to the corresponding bis‐pyrrole tetrols 3 in high yields. J. Heterocyclic Chem., 2011. 相似文献
9.
A systematic exploration of thiophilic ability of o-iodoxybenzoic acid (IBX) for oxidative desulfurization to trigger domino reactions leading to new methodologies for synthesis of different azoles is described. A variety of highly substituted oxadiazoles, thiadiazoles, triazoles, and tetrazoles have been successfully synthesized in good to excellent yields, starting from readily accessible thiosemicarbazides, bis-diarylthiourea, 1,3-disubtituted thiourea, and thioamides. 相似文献
10.
Gagana Karkada G Arun Maiya Praveen Arany Mohandas Rao KG Shalini Adiga Shobha U. Kamath 《Photochemistry and photobiology》2023,99(4):1172-1180
Individuals with diabetic foot ulcers have overlapped the inflammatory, proliferative and remodeling phase, making the tissue vulnerable to delayed healing responses. We aimed to establish the dose–response relationship of photobiomodulation therapy of different doses and matrix metalloproteinases in the healing dynamics of diabetic neuropathic ulcers. Diabetes was induced in 126 Albino Wistar rats, and neuropathy was induced to the hind paw by a sciatic nerve injury method. An excisional wound was created on the neuropathy-induced leg. Photobiomodulation therapy of dosages 4, 6, 8, 10, 12 and 15 J cm−2 and wavelength 655 nm and 808 nm was irradiated. Photobiomodulation therapy of dosages 4, 6 and 8 J cm−2 showed better wound healing properties with optimized levels of matrix metalloproteinases-1 and 8. We observed a strong dose response in the experimental group treated with 6 and 8 J cm−2. The findings from the present study conclude that photobiomodulation therapy of dosages 4, 6 and 8 J cm−2 is suggestive of usefulness in diabetic neuropathic ulcer healing. Markers like matrix metalloproteinases may give a clear direction on response to the therapy. Based on the findings from the present study, we recommend to validate the findings for safety and efficacy in future through human prospective randomized controlled clinical trials. 相似文献