ECD

ECD
  • 文章类型: Journal Article
    从科迪亚的果实中,11个新的酚类化合物,二分法A-K,被隔离,连同19种已知化合物。通过详细的NMR数据和HRESIMS数据的分析,证实了所有化合物的平面结构。使用NMR计算,通过比较观察到的和计算的电子圆二色性(ECD)光谱,阐明了二分法A-K的绝对构型。将双光菌素H(8)和双光菌素I(9)确定为两对对映异构体。化合物8和9的对映体采用手性相高效液相色谱(HPLC)分离,并且通过类似地计算ECD来确定每个对映异构体的立体结构。化合物3、5、7、17、18、23-25和27-30在30μg/mL的浓度下使葡萄糖摄取增加1.04-至2.85倍。进一步的研究表明,化合物3和5对L6细胞中的葡萄糖转运蛋白4(GLUT4)易位活性具有中等作用。在30μg/mL时,化合物3显著增强AMPK磷酸化和GLUT4表达。作为一个整体,化合物3有可能成为治疗2型糖尿病(T2DM)的候选药物。
    From the fruits of Cordia dichotoma, 11 new phenolic compounds, dichotomins A-K, were isolated, together with 19 known compounds. Through the analysis of detailed NMR data and HRESIMS data, the planar structures of all compounds were confirmed. Using NMR calculations, the absolute configuration of dichotomins A-K was elucidated by comparing their observed and computed electronic circular dichroism (ECD) spectra. Dichotomin H (8) and dichotomin I (9) were determined as two pairs of enantiomers. The enantiomers of compounds 8 and 9 were separated using chiral-phase high-performance liquid chromatography (HPLC), and the stereostructure of each enantiomer was determined by similarly calculating the ECD. Compounds 3, 5, 7, 17, 18, 23-25, and 27-30 increased glucose uptake by 1.04- to 2.85-folds at concentrations of 30 μg/mL. Further studies revealed that compounds 3 and 5 had a moderate effect on glucose transporter 4 (GLUT4) translocation activity in L6 cells. At 30 μg/mL, compound 3 significantly enhanced AMPK phosphorylation and GLUT4 expression. As a whole, compound 3 has the potential to be a drug candidate for the treatment of type 2 diabetes mellitus (T2DM).
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  • 文章类型: Journal Article
    本研究利用密度泛函理论(DFT)和波函数分析探讨了量子尺寸对[n]芳烃(n=5、6、7、8)光学性质的影响。研究了单光子吸收(OPA)和双光子吸收(TPA)光谱中的电子跃迁机理,以及这些系统的电子圆二色性(ECD)的计算。过渡密度矩阵(TDM)和电子-空穴对密度图用于研究电子激发特性,揭示了一个值得注意的大小依赖关系。对跃迁电偶极矩(TEDM)和跃迁磁偶极矩(TMDM)的分析揭示了柱[n]芳烃内部的电磁相互作用机制。拉曼光谱计算进一步阐明振动模式,在使用静电势(ESP)分析研究与外部环境的相互作用时,在外部磁场下评估电子离域,提供对这些超分子结构中磁感应电流现象的见解。通过从头算分子动力学(AIMD)研究了柱[n]芳烃的热稳定性。
    This study explores the quantum size effects on the optical properties of pillar[n]arene (n = 5, 6, 7, 8) utilizing density functional theory (DFT) and wave function analysis. The mechanisms of electron transitions in one-photon absorption (OPA) and two-photon absorption (TPA) spectra are investigated, alongside the calculation of electron circular dichroism (ECD) for these systems. Transition Density Matrix (TDM) and electron-hole pair density maps are employed to study the electron excitation characteristics, unveiling a notable size dependency. Analysis of the transition electric dipole moment (TEDM) and the transition magnetic dipole moment (TMDM) reveals the electromagnetic interaction mechanism within pillar[n]arene. Raman spectra computations further elucidate vibrational modes, while interactions with external environments are studied using electrostatic potential (ESP) analysis, and electron delocalization is assessed under an external magnetic field, providing insights into the magnetically induced current phenomena within these supramolecular structures. The thermal stability of pillar[n]arene was investigated by ab initio molecular dynamics (AIMD).
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  • 文章类型: Journal Article
    真菌在不同的培养条件下具有不同的遗传表达能力和生物合成途径,可以产生各种次生代谢产物。“一株多化合物”策略用于激活真菌的沉默生物合成基因以产生各种化合物,这是一种有效的方法。为了在食用菌Pholiotanameko中发现各种新化合物,已经采用了涉及前体进料和酶抑制剂添加的发酵策略。一种新的伊卢丹倍半萜(1),连同一种已知的吲哚二萜生物碱,从P.nameko的液体培养物的提取物中分离出克多孢菌素A(2)。通过1D和2DNMR的组合鉴定了新化合物,MS,旋光,和ECD计算。我们对所有分离的化合物对三种癌细胞系的细胞毒性进行了实验,但我们没有观察到任何显著的细胞毒性(IC50>40μM)。
    Fungi have different genetic expression abilities and biosynthetic pathways under different cultivation conditions, which can produce various secondary metabolites. The \"one strain many compounds\" strategy is used to activate silent biosynthetic genes of fungi to produce various compounds, which is an effective method. In order to discover various new compounds in the edible fungus Pholiota nameko, a fermentation strategy involving precursor feeding and enzyme inhibitor addition has been employed. A new illudane sesquiterpene (1), along with one known indole diterpenoid alkaloid, cladosporine A (2) were isolated from the extracts of liquid culture of P. nameko. The new compound was identified by combination of 1D and 2D NMR, MS, optical rotation, and ECD calculations. We conducted experiments on the cytotoxicity of all isolated compounds on three cancer cell lines, but we did not observe any significant cytotoxicity (IC50 > 40 μM).
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  • 文章类型: Journal Article
    从淫羊藿的叶子中分离出一种先前未描述的异戊烯化类黄酮(1)和三种已知类黄酮(2-4)。通过广泛的光谱分析并与文献中的NMR数据进行比较,确定了它们的结构。化合物1显示中等细胞毒性,IC50值为18.7μM,而已知的化合物2和3对Lewis肺癌细胞(LLC细胞)的IC50值分别为29.2和32.8μM,分别。
    One previously undescribed prenylated flavonoid (1) and three known ones (2-4) were isolated from leaves of Epimedium brevicornu maxim. Their structures were determined through extensive spectroscopic analysis and comparison with the NMR data in the literature. Compound 1 showed a moderate cytotoxicity with an IC50 value of 18.7 μM, while known compounds 2 and 3 elicited weak cytotoxicities with IC50 values of 29.2 and 32.8 μM against Lewis Lung cancer cells (LLC cells), respectively.
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  • 文章类型: Journal Article
    新疆阿魏(阿皮科)分布于新疆干旱的沙漠地区,其树脂是治疗消化道疾病的传统中药。为探索银杏的生物活性成分,分离出三种新的木脂素和13种已知成分。利用光谱分析和ECD计算建立了组分的结构阐明。Griess反应结果表明,新化合物1和2显著降低了LPS刺激的RAW264.7巨噬细胞中NO的产生,ELISA结果表明,它们通过抑制TNF-α有效减轻LPS诱导的炎症,IL-1β,和IL-6表达。计算机模拟方法证实化合物1以-5.84〜10.79kcal/mol的强结合能对接到受体中。此外,化合物6通过抑制细胞迁移和侵袭,抑制AGS胃癌细胞的增殖,IC50值为15.2μM。这项研究表明,新金鸡可能是生物活性成分的有希望的潜在资源。
    Ferula sinkiangensis K. M. Shen (Apiaceae) is distributed in arid desert areas of Xinjiang, and its resin is a traditional Chinese medicine to treat gastrointestinal digestive diseases. To explore bioactive components from F. sinkiangensis, three new lignans and thirteen known components were isolated. The structural elucidation of the components was established utilizing spectroscopic analyses together with ECD calculations. Griess reaction results indicated new compounds 1 and 2 significantly decreased NO production in LPS-stimulated RAW 264.7 macrophages, and ELISA results indicated that they effectively attenuated LPS-induced inflammation by inhibiting TNF-α, IL-1β, and IL-6 expressions. The in silico approach confirmed that compound 1 docked into the receptors with strong binding energies of -5.84~-10.79 kcal/mol. In addition, compound 6 inhibited the proliferation of AGS gastric cancer cells with IC50 values of 15.2 μM by suppressing the cell migration and invasion. This study disclosed that F. sinkiangensis might be a promising potential resource for bioactive components.
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  • 文章类型: Journal Article
    在这项工作中,介绍了三种高效圆偏振发光材料的物理机理。绘制了UV-vis光谱;使用跃迁密度矩阵(TDM)和电荷差密度(CDD)的组合研究了其电子在激发态下的跃迁性质;结合电子云的分布,阐述了三种结构中电荷转移激发的本质。计算了三种结构在S1和S2激发态下的共振拉曼光谱。M,M-4和M,通过电子圆二色性(ECD)光谱发现M-5结构产生新颖的手性,以及M的手性的原因,M-4和M,通过分析不同取向的跃迁电/磁偶极矩(TEDM/TMDMs)的密度,讨论了M-5结构。最后,M的拉曼光学活性(ROA),M-4和M,计算M-5,并绘制光谱。本研究将为碳基纳米材料在有机电子器件中的应用提供指导,太阳能电池,和光电子。
    In this work, the physical mechanisms of three highly efficient circularly polarized luminescent materials are introduced. The UV-vis spectra are plotted; the transition properties of their electrons at the excited states are investigated using a combination of the transition density matrix (TDM) and the charge difference density (CDD); combining the distribution of electron clouds, the essence of charge transfer excitation in three structures is explained. The resonance Raman spectrum of the three structures at the S1 and S2 excited states are calculated. The M, M-4 and M, M-5 structures are found to produce novel chirality by electronic circular dichroism (ECD) spectrum, and the reasons for the chirality of the M, M-4 and M, M-5 structures are discussed by analyzing the density of transition electric/magnetic dipole moments (TEDM/TMDMs) in different orientations. Finally, the Raman optical activity (ROA) of M, M-4, and M, M-5 are calculated, and the spectra are plotted. This study will provide guidance for the application of carbon-based nanomaterials in organic electronic devices, solar cells, and optoelectronics.
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  • 文章类型: Journal Article
    新型达玛烷型三萜皂苷,命名为22(R)-三七皂苷Ab1(1),从黑参的EtOH提取物中分离出13种已知的达玛烷型三萜皂苷(2-14),并根据一维和二维NMR(包括1H-NMR,13C-NMR,HSQC,HMBC,ROESY)并计算了ECD。其中,化合物1-2和6-8为首次从人参和黑参中分离得到。此外,首次通过ECD区分了22(R)-和22(S)-三七皂苷Ab1的绝对结构。
    New dammarane-type triterpenoid saponin, named 22(R)-notoginsenoside Ab1 (1), together with thirteen known dammarane-type triterpenoid saponins (2-14) was isolated from the EtOH extract of black ginseng and their structures were elucidated on the basis of one- and two-dimensional NMR (including 1H-NMR, 13C-NMR, HSQC, HMBC, ROESY) and calculated ECD. Among them, compounds 1-2 and 6-8 were isolated for the first time from ginseng and black ginseng. Besides, the absolute structure of 22(R)- and 22(S)- notoginsenoside Ab1 were distinguished by ECD for the first time.
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  • 文章类型: Case Reports
    背景:Erdheim-Chester病(ECD)是一种罕见的组织细胞疾病,其特征是多系统黄色肉芽肿性浸润被脂质负载的组织细胞。我们报告了两例涉及眼眶的ECD病例,并描述了其临床病理因素,治疗,和预后。一例是罕见的ECD并发原发性血小板增多症。
    方法:本研究描述了两名双侧眼眶ECD患者。均表现为眼球突出和视力丧失;影像学发现显示双侧眶内肿块。两者均有不同程度的全身症状(胸腔积液,心包积液,腹水,和心力衰竭)之前出现眼部症状,并且在眼科肿瘤切除和病理活检之前未找到原因。经病理活检和检测BRAFV600E突变后确诊为ECD。患者2还患有原发性血小板增多症并且具有CALR突变以及BRAFV600E突变。建议两名患者接受靶向治疗。患者1出于经济原因拒绝靶向治疗,仅在局部放疗后出院。患者的两只眼睛都没有光感知,全身症状也没有改善。患者2在诊断后开始靶向治疗,2周后达到出院标准。他目前情况良好,但不幸的是,由于他的视觉功能受到不可逆转的损害,他的视力没有改善。
    结论:ECD罕见且临床表现多样,易误诊和漏诊。轨道受累在ECD中很常见,手术是最常用的方法。尽管手术切除并不能治愈,其意义在于活检以建立诊断和/或手术减积以减轻肿块效应,尽量减少视觉功能的进一步损害。靶向治疗是BRAF突变基因阳性患者最有效的治疗方法。在启动难治性ECD的靶向治疗之前,评估伴随的骨髓性肿瘤也至关重要。
    BACKGROUND: Erdheim-Chester disease (ECD) is a rare histiocytic disorder characterized by multisystem xanthogranulomatous infiltration by lipid-laden histiocytes. We report two cases of ECD involving the orbit and describe their clinicopathologic factors, treatments, and prognosis. One was a rare case of ECD complicated with primary thrombocytosis.
    METHODS: This study describes two patients with bilateral orbital ECD. Both presented with proptosis and visual loss; imaging findings showed bilateral intraorbital masses. Both had different degrees of systemic symptoms (pleural effusion, pericardial effusion, ascites, and heart failure) before the ocular symptoms and did not find the cause before ophthalmic tumor resection and pathological biopsy. The diagnosis of ECD was confirmed after pathological biopsy and detection of BRAFV600E mutation. Patient 2 also with primary thrombocytosis and had a CALR mutation as well as the BRAFV600E mutation. Both patients were recommended to receive targeted therapy. Patient 1 refused targeted therapy for financial reasons and was discharged after local radiotherapy only. The patient had no light perception in either eye and no improvement in systemic symptoms. Patient 2 began targeted treatment after diagnosis and reached the discharge criteria 2 weeks later. He is in good condition at present, but unfortunately, his eyesight has not improved because of the irreversible damage to his visual function.
    CONCLUSIONS: ECD is easily misdiagnosed and missed because of its rarity and diverse clinical manifestations. Orbital involvement is common in ECD, and surgery is the most frequently employed approach. Despite the surgical resection is not curative, its significance lies in biopsy to establish diagnosis and/or surgical debulking to relieve mass effect, minimizing further impairment of visual function. Targeted therapy is the most effective treatment for patients with a positive BRAF mutation gene. Evaluation of a concomitant myeloid neoplasm is also critical before initiating targeted therapies for refractory ECD.
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  • 文章类型: Journal Article
    基于二维(2D)材料的范德华(vdW)异质结,石墨烯和过渡金属二硫属化合物(TMD),是未来光电和激子器件的研究热点。无键vdW相互作用是2D材料异质结器件可靠性和稳定性的关键。然而,目前对二维叠层材料异质结构的研究主要集中在光学性质和电子结构上。此外,基于文献中的定性描述和能量范围,研究和理解了2D异质结构中的vdW相互作用。基于对2D堆叠材料之间vdW相互作用的定量强度和微观机理的实际计算,对vdW相互作用的性质研究很少。因此,本文探讨了二维材料堆叠双层结构之间的vdW相互作用,包括双层石墨烯,石墨烯/MoS2和石墨烯/WS2异质结构,重点对vdW相互作用的能量成分进行定量分析。我们首先通过非共价相互作用(NCI)分析,在三个堆叠的双层结构中观察到弱相互作用,并发现相互作用集中在两层结构之间的结合区域。我们主要通过基于力场(EDA-FF)方法的能量分解分析,对三个2D材料双层异质结构中的弱相互作用能进行分解,并获得了三个成分-静电能的能量值和比例,交换二维堆叠双层结构之间总结合能的排斥能和分散能。vdW相互作用能是交换排斥能和分散能的总和,vdW相互作用的分散能占2D双层堆叠结构之间弱相互作用的结合能的60%以上。双层结构中的vdW强度约为177.07、123.85和133.93kJ/mol,比经典定义的vdW能量0.1-10kJ/mol大大约1-2个数量级。此外,我们计算三个二维堆叠结构的状态密度,并进一步获得HOMO-LOMO信息;进一步了解石墨烯/MoS2和石墨烯/WS2异质结构的电子结构,我们计算了它们的光学吸收光谱和电子圆二色性(ECD)光谱。根据计算结果,这两个异质结构在可见光区都有很强的吸收峰,强吸收峰的电荷转移形式可以根据电荷转移图确定。ECD谱表明石墨烯/MoS2和石墨烯/WS2异质结构的构型具有较大的手性。我们的工作有助于更深入地了解2D堆叠材料中弱相互作用和光学特性的性质,这对构建稳定的2D异质结构结构和开发多功能2D器件具有根本性的推动作用。该研究有利于进一步推动强光电和激子2D异质结器件的基础研究和实际开发。
    van der Waals (vdW) heterojunctions based on two-dimensional (2D) materials, graphene and transition metal dichalcogenides (TMDs), are a research hotspot for future optoelectronic and exciton devices. Bond-free vdW interactions are key to 2D material heterojunction device reliability and stability. However, most of the current research on 2D stacked materials heterostructures mainly focuses on optical properties and electronic structure. Furthermore, vdW interaction in 2D heterostructures is studied and understood on the basis of qualitative description and energy ranges from the literature. There are few studies on the nature of vdW interaction based on practical calculations of the quantitative strength and microscopic mechanism of vdW interaction between 2D stacked materials. Therefore, this paper explores the vdW interaction between 2D material stacked bilayer structures, including bilayer graphene, graphene/MoS2 and graphene/WS2 heterostructures, focusing on quantitative analysis of the energy components of the vdW interaction. We first visually observed the weak interactions in the three stacked bilayer structures through noncovalent interaction (NCI) analysis, and found that the interactions are concentrated in the binding region between the two-layer structures. We mainly decomposed the weak interaction energy in the three 2D material bilayer heterostructures through energy decomposition analysis based on the force field (EDA-FF) method and obtained the energy values and proportions of the three components-electrostatic energy, exchange repulsion energy and dispersion energy of the total binding energy between the 2D stacked bilayer structures. The vdW interaction energy is the sum of the exchange repulsion energy and dispersion energy, and the dispersion energy of the vdW interaction accounts for more than 60% of the binding energy of the weak interaction between the 2D bilayer stacked structures. The vdW strengths in the bilayer structures are on the order of 177.07, 123.85, and 133.93 kJ/mol, approxmately 1-2 orders of magnitude larger than the classically defined vdW energies of 0.1-10 kJ/mol. Furthermore, we calculate the density of states of the three 2D stacked structures, and further obtained HOMO-LOMO information; to further understand the electronic structures of the graphene/MoS2 and graphene/WS2 heterostructures, we calculated their optical absorption spectra and electron circular dichroism (ECD) spectra. According to the calculation results, the two heterostructures have strong absorption peaks in the visible region, and the charge transfer forms at the strong absorption peak can be determined according to the charge transfer diagram. The ECD spectra indicate that the configurations of the graphene/MoS2 and graphene/WS2 heterostructures have large chirality. Our work contributes to a deeper understanding of the nature of the weak interactions and optical properties in 2D stacked materials, which plays a fundamental role in promoting the construction of stable 2D heterostructure configurations and the development of multifunctional 2D devices. The research is conducive to further promoting the basic research and practical development of strong optoelectronic and excitonic 2D heterojunctions devices.
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  • 文章类型: Journal Article
    六种新的环烯醚萜类衍生物(1-6),以及十二个已知化合物(7-18),从CatalpaOvataG.Don的干果中分离并鉴定。它们的化学结构主要通过相对光谱数据来确定,同时在电子圆二色性计算上阐明了化合物2和3的绝对构型。通过体外激活293T细胞中的Nrf2转录途径来评估它们的抗氧化活性。其中,与25μM的对照组相比,化合物1、3、4、6-8、10-12、14、15、17和18显示出显著的Nrf2激动作用。最后,讨论了1-13的假想生物合成途径。
    Six new iridoid derivatives (1-6),together with twelve known compounds (7-18), were isolated and identified from the dried fruits of Catalpa ovata G. Don. Their chemical structures were mainly established through the relative spectroscopic data, while the absolute configurations of compounds 2 and 3 were elucidated on the electronic circular dichroism calculations. Their antioxidant activities were evaluated by activating the Nrf2 transcriptional pathway in 293 T cells in vitro. Among them, Compounds 1, 3, 4, 6-8, 10-12, 14, 15, 17 and 18 showed significant Nrf2 agonistic effect compared with the control group at 25 μM. Finally, The hypothetical biosynthetic pathway for 1-13 was discussed.
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