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111.
Laila Rubab Sumbal Afroz Sajjad Ahmad Saddam Hussain Iram Nawaz Ali Irfan Fozia Batool Katarzyna Kotwica-Mojzych Mariusz Mojzych 《Molecules (Basel, Switzerland)》2022,27(5)
Coumarin is an important six-membered aromatic heterocyclic pharmacophore, widely distributed in natural products and synthetic molecules. The versatile and unique features of coumarin nucleus, in combination with privileged sulfonamide moiety, have enhanced the broad spectrum of biological activities. The research and development of coumarin, sulfonamide-based pharmacology, and medicinal chemistry have become active topics, and attracted the attention of medicinal chemists, pharmacists, and synthetic chemists. Coumarin sulfonamide compounds and analogs as clinical drugs have been used to cure various diseases with high therapeutic potency, which have shown their enormous development value. The diversified and wide array of biological activities such as anticancer, antibacterial, anti-fungal, antioxidant and anti-viral, etc. were displayed by diversified coumarin sulfonamides. The present systematic and comprehensive review in the current developments of synthesis and the medicinal chemistry of coumarin sulfonamide-based scaffolds give a whole range of therapeutics, especially in the field of oncology and carbonic anhydrase inhibitors. In the present review, various synthetic approaches, strategies, and methodologies involving effect of catalysts, the change of substrates, and the employment of various synthetic reaction conditions to obtain high yields is cited. 相似文献
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Kulsoom Zahara Yamin Bibi Saadia Masood Sobia Nisa Ahmad Sher Naushad Ali Sunjeet Kumar Abdul Qayyum Waseem Ahmed Rokayya Sami Amina A. M. Al-Mushhin Amani H. Aljahani 《Molecules (Basel, Switzerland)》2022,27(6)
The genus Bidens a member of family Compositae, is widely documented as an ethno-medicinally important genus of plants. In the present study, anticancer potential of three ethno-medicinally important species i.e., B. bipinnata, B. biternata and B. pilosa were tested. For in-vitro evaluation, an MTT (Thiazolyl blue tetrazolium bromide) assay was performed against cervical cancer cells (HeLa), hepatocellular carcinoma (HepG), and adenocarcinoma human alveolar basal epithelial cells (A549). For in vivo evaluation, Artemia salina, Danio rerio, and Caenorhabditis elegans were used. Among all the tested extracts, the ethanol extract of B. biternata appeared to have highest anticancer activity, and the compounds responsible for this activity were identified to be Tris (2,4-di-tert-butylphenyl), 4-hydroxy-2,4′-dimethoxychalcone, and 2,4-di-tert-butylphenol. This is the first report of the isolation of Tris (2,4-di-tert-butylphenyl) phosphate from the genus Bidens and the first report of 4-hydroxy-2,4′-dimethoxychalcone and 2,4-di-tert-butylphenol from B. biternata. Among the isolated compounds, 4-hydroxy-2,4′-dimethoxychalcone showed the highest anticancer activity with an LD50 value of 236.7 µg/mL. Therefore, this compound carries promising potential for being established as a pharmaceutical for chemoprevention and chemotherapy. 相似文献
114.
Seyed Ali Salehizadeh Dariush Souri 《Journal of Physics and Chemistry of Solids》2011,72(11):1381-1385
The glass transition temperature dependence to heating rate and therefore the activation energy (ΔH?) of the glass transition of (60-x)V2O5–xNiO–40TeO2 oxide glasses with 0≤x≤20 (in mol%) were investigated at heating rates φ (=3 6, 9, 10 and 12 K/min) using differential scanning calorimetry (DSC). The heating rate dependence of Tg was used to investigate the applicability of different theoretical models describing the glass transition. Using the application of Moynihan and Kissinger et al. models to the present data, different values of (ΔH?) at each different heating-rate regions were obtained. The fragility parameter (m=ΔH?/R Tg) was ∼24.98 for x=10 mol%, suggesting that this glass may be considered as a rather strong glass (fragility index m∼>20 is an indication of fragile glass). Also the compositional dependence of Tg and ΔH? was investigated. 相似文献
115.
We report on room temperature ferromagnetism in C-doped ZnO thin films prepared by electron beam evaporation. Magnetization, Hall effect, X-ray photoemission spectroscopy (XPS) and X-ray diffraction studies have been conducted to investigate the source and nature of ferromagnetism in C-doped ZnO. The samples were observed to have n-type conduction with the carrier concentration increasing with C doping. XPS does not give any evidence for C substituted at the O site, and is more consistent with the formation of C-O bonds and with the presence of C primarily in the +4 state. It is suggested that the ferromagnetism originates in the development of Zn vacancies that are stabilized due to the incorporation of C in a high valence state (C4+). 相似文献
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118.
Giovanna Calò Gaetano Bellanca Ali Emre Kaplan Paolo Bassi Vincenzo Petruzzelli 《Optical and Quantum Electronics》2018,50(6):261
In this paper we present a double plasmonic Vivaldi antenna for on-chip optical wireless communication. The proposed antenna is a two-element broadside array fed by a silicon waveguide. The designs of the power splitter and of the hybrid Si-plasmonic coupler used for antenna excitation are described in detail. The array radiation characteristics are optimized through Finite Difference Time Domain simulations and the performance of a point-to-point link is evaluated. The proposed double Vivaldi array increases the gain of 3 dB with respect to a single antenna, improving the received power on a link of 6 dB when the double antenna is used for both transmitting and receiving sections. 相似文献
119.
Ashkan Ghanbari Alireza Kashaninia Ali Sadr Hamed Saghaei 《Optical and Quantum Electronics》2018,50(11):411
In this paper, femtosecond optical pulses compression and supercontinuum generation in a triangular silicon photonic crystal fiber at 2500 nm are investigated. A region of large minimum anomalous group velocity dispersion, negligible higher order dispersions and unique nonlinearity of silicon are used to demonstrate compression of 100 fs initial input optical pulses to 2.5 fs and ultra-broadband supercontinuum generation with very low input pulse energy over short distances of the fiber. 相似文献
120.
Ali Asghar Mohammadi Salman Taheri Arman Amini Reza Ahdenov 《Molecular diversity》2018,22(4):999-1006
Triamide derivatives have been synthesized in good yields in a novel, one-pot, five-component, and efficient process by the reaction of Z-oxazolone, water, primary amines, aldehydes, isocyanides, in the presence of catalytic amount of KAl(SO4)2·12H2O (alum) as a non-toxic, reusable, inexpensive, and easily available reagent via Ugi reaction in aqueous solution. 相似文献