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31.
Cosmetic industries are highly committed to finding natural sources of functional active constituents preferable to safer materials to meet consumers’ demands. Marine macroalgae have diversified bioactive constituents and possess potential benefits in beauty care products. Hence, the present study was carried out to characterize the biochemical profile of marine macroalga Chaetomorpha crassa by using different techniques for revealing its cosmetic potentials. In results, the FTIR study characterized the presence of different bioactive functional groups that are responsible for many skin-beneficial compounds whereas six and fifteen different important phycocompounds were found in GCMS analysis of ethanolic and methanolic extracts, respectively. In the saccharide profile of C. crassa, a total of eight different carbohydrate derivatives were determined by the HRLCMS Q-TOF technique, which showed wide varieties of cosmetic interest. In ICP AES analysis, Si was found to be highest whereas Cu was found to be lowest among other elements. A total of twenty-one amino acids were measured by the HRLCMS-QTOF technique, which revealed the highest amount of the amino acid, Aspartic acid (1207.45 nmol/mL) and tyrosine (106.77 nmol/mL) was found to be the lowest in amount among other amino acids. Their cosmetic potentials have been studied based on previous research studies. The incorporation of seaweed-based bioactive components in cosmetics has been extensively growing due to its skin health-promoting effects.  相似文献   
32.
Imidazolidine and thiazolidine-based isatin derivatives (IST-01–04) were synthesized, characterized, and tested for their interactions with ds-DNA. Theoretical and experimental findings showed good compatibility and indicated compound–DNA binding by mixed mode of interactions. The evaluated binding parameters, i.e., binding constant (Kb), free energy change (ΔG), and binding site sizes (n), inferred comparatively greater and more spontaneous binding interactions of IST-02 and then IST-04 with the DNA, among all compounds tested under physiological pH and temperature (7.4, 37 °C). The cytotoxic activity of all compounds was assessed against HeLa (cervical carcinoma), MCF-7 (breast carcinoma), and HuH-7 (liver carcinoma), as well as normal HEK-293 (human embryonic kidney) cell lines. Among all compounds, IST-02 and 04 were found to be cytotoxic against HuH-7 cell lines with percentage cell toxicity of 75% and 66%, respectively, at 500 ng/µL dosage. Moreover, HEK-293 cells exhibit tolerance to the increasing drug concentration, suggesting these two compounds are less cytotoxic against normal cell lines compared to cancer cell lines. Hence, both DNA binding and cytotoxicity studies proved imidazolidine (IST-02) and thiazolidine (IST-04)-based isatin derivatives as potent anticancer drug candidates among which imidazolidine (IST-02) is comparatively the more promising.  相似文献   
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34.
Using structure-based virtual screening approach, a coumarin derivative (1) was identified as β-glucuronidase inhibitor. A focused library of coumarin derivatives was synthesized by eco-benign version of chemical reaction, and all synthetic compounds were characterized by using spectroscopy. These compounds were found to be inhibitor of β-glucuronidase with IC50 values in a micromolar range. All synthetic compounds exhibited interesting inhibitory activity against β-glucuronidase, however, their potency varied substantially from IC50 = 9.9–352.6 µM. Of twenty-one compounds, four exhibited a better inhibitory profile than the initial hit 1. Interestingly, compounds 1e, 1k, 1n and 1p exhibited more potency than the standard inhibitor with IC50 values 34.2, 21.4, 11.7, and 9.9 µM, respectively. We further studied their dose responses and also checked our results by using detergent Triton ×-100. We found that our results are true and not affected by detergent.  相似文献   
35.
In the present article, Kantorovich variant of λ‐Bernstein operators with shifted knots are introduced. The advantage of using shifted knot is that one can do approximation on [0,1] as well as on its subinterval. In addition, it adds flexibility to operators for approximation. Some basic results for approximation as well as rate of convergence of the introduced operators are established. The rth order generalization of the operator is also discussed. Further for comparisons, some graphics and error estimation tables are presented using MATLAB.  相似文献   
36.
Catalytic carbene-transfer reactions constitute a class of highly useful transformations in organic synthesis. Although catalysts based on a range of transition-metals have been reported, the readily accessible nickel(II)-based complexes have been rarely used. Herein, an air-stable nickel(II)-carborane complex is reported as a well-defined, versatile and recyclable catalyst for selective carbene transfer reactions with low catalyst loading under mild conditions. This catalyst is effective for several types of reactions including diastereoselective cyclopropanation, epoxidation, selective X−H insertions (X = C, N, O, S, Si), particularly for the unprotected substrates. This represents a rare example of carborane ligands in base metal catalysis.  相似文献   
37.
Molecular Diversity - Novel ibuprofen derivatives 1–19 including ibuprofen hydrazide 1, and substituted thiourea derivatives 2–19 were synthesized and characterized by EI-MS, FAB-MS,...  相似文献   
38.
An improved method for the synthesis of L-amino acids as their benzoxymethyl esters has been reported. All the synthesized compounds were characterized by (1)H NMR, EI-MS and IR spectroscopic methods.  相似文献   
39.
A simplified method for determining the sequence and branching of oligosaccharides using infrared multiphoton dissociation (IRMPD) in a quadrupole ion trap (QIT) is described. An IR-active boronic acid (IRABA) reagent is used to derivatize the oligosaccharides before IRMPD analysis. The IRABA ligand is designed to both enhance the efficiency of the derivatization reaction and to facilitate the photon absorption process. The resulting IRMPD spectra display oligosaccharide fragments that are formed from primarily one type of diagnostic cleavage, thus making sequencing straightforward. The presence of sequential fragment ions, a phenomenon of IRMPD, permit the comprehensive sequencing of the oligosaccharides studied in a single stage of activation. We demonstrate this approach for two series of oligosaccharides, the lacto-N-fucopentaoses (LNFPs) and the lacto-N-difucohexaoses (LNDFHs).  相似文献   
40.
Two new flavonol glycosides, brachysides C and D, together with three known flavonol glycosides, were isolated from the leaves of Caragana brachyantha. The structures of brachysides C and D were elucidated on the basis of detailed spectroscopic analysis as quercetin 5-O-[α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside]-7-O-[α-l-rhamnopyranoside] and quercetin 5-O-[α-l-rhamnopyranosyl-(1 → 6)-β-d-glucopyranoside]-7-O-[α-l-rhamnopyranoside]-4′-O-[α-l-rhamnopyranoside], respectively. The presence of flavonol tetra- and triglycosides bearing a sugar moiety at position 5 was the first report from this genus Caragana.  相似文献   
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