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81.
In reactions of 3-(2-amino-3-pyridyl)amino-5,5-dimethylcyclohex-2-en-1-one with aromatic aldehydes (2- and 4-hydroxy-, 2-hydroxy-3-methoxy-, 4-dimethylamino-, 4-methoxy-, 2,4- and 3,4-dimethoxy-, 3,4-methylenedioxy-, 4-bromo-, 4-fluoro-, 4-chloro-, 2-nitro- and 3-nitrobenzaldehydes, furfural, and 2-thiophenecarbaldehyde), we have obtained the corresponding 10-aryl-7,7-dimethyl-5,6,7,8,9,10-hexahydro-11H-pyrido[3,2-b][1,4]benzodiazepin-9-ones. 相似文献
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84.
Rumex confertus belongs to the genus Rumex and is classified as an invasive parasitic plant in agriculture. Despite other Rumex species being widely used in herbal medicine due to their antimicrobial, antioxidant, antitumor, and anti-inflammatory effects, there are almost no information about the potential of Rumex confertus for the treatment of various diseases. In this review we analyzed scientific articles revealing properties of Rumex plant’s substances against cancer, diabetes, pathogenic bacterial invasions, viruses, inflammation, and oxidative stress for the past 20 years. Compounds dominating in each composition of solvents for extraction were discussed, and common thin layer chromatography(TLC) and high performance liquid chromatography(HPLC) methods for efficient separation of the plant’s extract are included. Physico-chemical properties such as solubility, hydrophobicity (Log P), pKa of flavonoids, anthraquinones, and other derivatives are very important for modeling of pharmacokinetic and pharmacodynamics. An overview of clinical studies for abounded selected substances of Rumex species is presented. 相似文献
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Theoretical studies on structure and performance of [1,2,5]‐oxadiazolo‐[3,4‐d]‐pyridazine‐based derivatives 下载免费PDF全文
Ke Wang Yuanjie Shu Ning Liu Weipeng Lai Tao Yu Xiaoyong Ding Zongkai Wu 《Journal of Physical Organic Chemistry》2017,30(1)
Based on energetic compound [1,2,5]‐oxadiazolo‐[3,4‐d]‐pyridazine, a series of functionalized derivatives were designed and first reported. Afterwards, the relationship between their structure and performance was systematically explored by density functional theory at B3LYP/6‐311 g (d, p) level. Results show that the bond dissociation energies of the weakest bond (N–O bond) vary from 157.530 to 189.411 kJ · mol?1. The bond dissociation energies of these compounds are superior to that of HMX (N–NO2, 154.905 kJ · mol?1). In addition, H1, H2, H4, I2, I3, C1, C2, and D1 possess high density (1.818–1.997 g · cm?3) and good detonation performance (detonation velocities, 8.29–9.46 km · s?1; detonation pressures, 30.87–42.12 GPa), which may be potential explosives compared with RDX (8.81 km · s?1, 34.47 GPa ) and HMX (9.19 km · s?1, 38.45 GPa). Finally, allowing for the explosive performance and molecular stability, three compounds may be suggested as good potential candidates for high‐energy density materials. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
87.
现代红外光谱技术以其分析速度快、重现性好、成本低、且不消耗样品等特点正得到越来越广泛的应用,文章利用傅里叶红外技术,研究了9种含有吲哚基和苯基的3-取代苯基-5-(3'-吲哚基)-异(噁)唑啉衍生物的红外光谱的特征吸收规律,指出了这类化合物不同取代基对红外吸收谱带的影响;同时,利用核磁共振技术,对3-取代苯基-5-(3'-吲哚基)-异(噁)唑啉衍生物的1H NMR的共振谱带做了全面的归属,其化学位移的变化规律与红外光谱一致,为这类化合物的结构与谱学研究提供了一条很好的途径. 相似文献
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This paper is mainly concerned with elastic and acoustic properties of vitrous silica besides the computation of phonon frequencies.
Thus the phonon frequencies of vitrous silica have been calculated assuming the electronic bulk modulus,K
e, as equal to zero. New equations have been derived to relate the pressure derivatives of second order elastic constants to
the acoustic Gruneisen’s parameters using both Bhatia-Singh’s parameters and Schofield’s equations. The calculated longitudinal
and transverse Gruneisen’s parameters and the predicted absorption band spectra from Nagendranath’s equation and Bhatia Singh’s
parameters are in good agreement with experiment. The calculated mean acoustic mode Gruneisen’s parameter evaluated from the
pressure derivative of Nagendranath’s equation is also in good agreement with experiment.
An erratum to this article is available at . 相似文献
90.
将液晶基团引入到载流子传输材料中合成了新型液晶性噁二唑类衍生物E3和E6,利用偏光显微镜、差热扫描和广角X射线衍射的方法对其液晶性进行了研究,结果表明,E3为单向近晶型液晶,E6为双向近晶型液晶。同时,利用紫外—可见吸收光谱和电化学方法测定了材料的能级结构参数,其高的LUMO能级。低的HOMO能级(相对真空能级)及较大的带隙表明,它们不仅有利于电子从阴极的注入,还对空穴和激子具有一定的阻挡作用。由于材料在有序的近晶相比在无序的各向同性相将具有高的载流子迁移率,因此将液晶性与传输性相结合对提高材料载流子迁移率具有非常重要的意义。 相似文献