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491.
Avnesh Kumari Sudesh Kumar Yadav Yogesh B. Pakade Vineet Kumar Bikram Singh Abha Chaudhary Subhash Chandra Yadav 《Colloids and surfaces. B, Biointerfaces》2011,82(1):224-232
The plant isolated antioxidant quercitrin has been encapsulated on poly-d,l-lactide (PLA) nanoparticles by solvent evaporation method to improve the solubility, permeability and stability of this molecule. The size of quercitrin-PLA nanoparticles is 250 ± 68 nm whereas that PLA nanoparticles is 195 ± 55 nm. The encapsulation efficiency of nanoencapsulated quercitrin evaluated by HPLC and antioxidant assay is 40%. The in vitro release kinetics of quercitrin under physiological condition reveals initial burst release followed by sustained release. Less fluorescence quenching is observed with equimolar concentration of PLA encapsulated quercitrin than free quercitrin. The presence of quercitrin specific peaks on FTIR of five times washed quercitrin loaded PLA nanoparticles provides an extra evidence for the encapsulation of quercitrin into PLA nanoparticles. These properties of quercitrin nanomedicine provide a new potential for the use of such less useful highly active antioxidant molecule towards the development of better therapeutic for intestinal anti-inflammatory effect and nutraceutical compounds. 相似文献
492.
Dr. Soumen Dutta Akshay Gurumoorthi Shinbi Lee Sun Woo Jang Dr. Nitee Kumari Yu-Rim Hong Prof. Dr. Wonyong Choi Prof. Dr. Chang Yun Son Prof. Dr. In Su Lee 《Angewandte Chemie (International ed. in English)》2023,62(28):e202303890
Herein, by choosing few-nm-thin two-dimensional (2D) nanocrystals of MOF-5 containing in-planner square lattices as a modular platform, a crystal lattice-guided wet-chemical etching has been rationally accomplished. As a result, two attractive pore patterns carrying Euclidean curvatures; precisely, plus(+)-shaped and fractal-patterned pores via ⟨100⟩ and ⟨110⟩ directional etching, respectively, are regulated in contrast to habitually formed spherical-shaped random etches on MOF surface. In agreement with the theoretical calculations, a diffusion-limited etching process has been optimized to devise high-yield of size-tunable fractal-pores on the MOF surface that tenders for a compatibly high payload of catalytic ReI-complexes using the existing large edge area once modified into a free amine-group-exposed inner pore surface. Finally, on benefiting from the long-range fractal opening in 2D MOF support structure, while loaded on an electrode surface, a facilitated cross-interface charge-transportation and well-exposure of immobilized ReI-catalysts are anticipated, thus realizing enhanced activity and stability of the supported catalyst in photoelectrochemical CO2-to-CO reduction. 相似文献
493.
Varaprasad Bodala Rajitha Lakshmi Podugu Kumari Yettula Dr. Padmarao Gollamudi Dr. Siddaiah Vidavalur Dr. Shyamala Pulipaka 《化学:亚洲杂志》2023,18(1):e202201004
A direct access to unsymmetrical and symmetrical multi-substituted pyridines has been accomplished via iron-catalysed [3+3] annulation of oxime acetates with enaminones. This protocol is featured by easily available starting materials, no requirement of expensive additives and ligands, operational simplicity, and good tolerance with diverse functional groups. 相似文献
494.
495.
Harshita Shet Manisha Patel Jyoti M. Waikar Dr. Pavan M. More Dr. Yogesh S. Sanghvi Dr. Anant R. Kapdi 《化学:亚洲杂志》2023,18(1):e202201006
The dimethylamino functionality has significant importance in industrially relevant molecules and methodologies to install these efficiently are highly desirable. We report herein a highly efficient, room-temperature dimethylamination of chloroheteroarenes performed via the in-situ generation of dimethylamine using N,N-dimethylformamide (DMF) as precursor wiith a large substrate scope that includes various heteroarenes, purines as well as commercially relevant drugs such as altretamine, ampyzine and puromycin precursor. 相似文献
496.
A one‐pot four component condensation of isatin, sarcosine, 2‐[2‐oxo‐1‐(prop‐2‐ynyl)indolin‐3‐ylidene]malononitrile and aryl azides has been reported for the synthesis of novel dispirooxindole pyrrolidine linked 1,2,3‐triazole conjugates using Cu(I) as a catalyst in PEG‐400 by stereoselective [3 + 2] azide‐alkyne cycloaddition followed by [3 + 2] azomethine ylide and alkene cycloaddition. Structures have been confirmed by spectral and X‐ray studies. Crystal packing of 5a has also been reported. Rapid reaction, easy work‐up and high yields are the salient features of the present protocol. 相似文献