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131.
Phenols are condensed with cinnamic acids in the presence of trifluoroacetic acid to give high yields of the corresponding 2(3H) benzofuranones. 相似文献
132.
Dushyant Singh Raghuvanshi Krishna Nand Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2243-2248
A simple, rapid, and efficient method for the synthesis of some new thiazolidinone and thiohydantoin derivatives of isatins along with some Mannich bases has been achieved in excellent yield from indole-2,3-dione-3-thiosemicarbazone employing microwave irradiation. 相似文献
133.
Alok Chaturvedi Chandra S. Sharma Padam N. Nagar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1923-1929
Reactions of triorganotin chlorides with potassium salt of O-alkyl trithiophosphate [ROP(S)(SK)2; R = Me, Pri, Ph] in 2:1 molar ratio in anhydrous benzene yield triorganotin O-alkyl trithiophosphate of the type ROP(S) [SSnR′3]2 R = Me, Pri; Ph, R′ = Prn, Bun, Ph] which are found to be monomeric in nature. These complexes are soluble in common organic solvents. Similar reactions of diorganotin chloride with dipotassium salt of S-alkyl trithiophosphate yield diorganotin-S-alkyl trithiophosphate of the type [(RS)P(O)S2]2SnR′2; R = Me, Pri; R′ = Me, Et, Ph, which also are found to be monomeric in nature and are soluble in common organic solvents. The newly synthesized derivatives have been characterized by physicochemical and spectroscopic techniques, IR, NMR (1H, 31P, and 119Sn). 相似文献
134.
Satish Kumar Singh Krishna Nand Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):94-97
Abstract A new, mild, and efficient protocol for the one-pot synthesis of O-alkyl-S-methyl dithiocarbonates (xanthates) has been described in reasonably good yields from a variety of alcohols employing carbon disulfide and methyl iodide using superoxide ion at room temperature. GRAPHICAL ABSTRACT 相似文献
135.
Semi‐interpenetrating polymeric networks of chitosan and poly(vinyl alcohol) [PVA] were prepared by varying the ratio of the constituents. The hydrogels were crosslinked using genipin, a naturally occurring nontoxic cross‐linking agent. The swelling behavior of these hydrogels was studied by immersing the films in deionized water at various temperatures and in buffer solutions of different pH. The states of water in the hydrogels, swollen at 25°C and pH 7, were determined using Differential Scanning Calorimetry (DSC). The swelling behavior of the gels was found to be dependent on temperature and pH of the medium. The amount of freezing water in the swollen hydrogels increased, whereas the amount of nonfreezing bound water remained more or less the same with increasing PVA concentration. 相似文献
136.
Juwar Doley Lakshya Veer Singh G. Ravi Kumar Aditya Prasad Sahoo Lovleen Saxena Uttara Chaturvedi Shikha Saxena Rajiv Kumar Prafull Kumar Singh R. S. Rajmani Lakshman Santra S. K. Palia S. Tiwari D. R. Harish Arvind Kumar G. S. Desai Smita Gupta Shishir K. Gupta A. K. Tiwari 《Applied biochemistry and biotechnology》2014,172(1):497-508
The canine parvovirus type 2 (CPV-2) causes an acute disease in dogs. It has been found to induce cell cycle arrest and DNA damage leading to cellular lysis. In this paper, we evaluated the apoptotic potential of the “new CPV-2a” in MDCK cells and elucidated the mechanism of the induction of apoptosis. The exposure of MDCK cells to the virus was found to trigger apoptotic response. Apoptosis was confirmed by phosphatidylserine translocation, DNA fragmentation assays, and cell cycle analysis. Activation of caspases-3, -8, -9, and -12 and decrease in mitochondrial potential in CPV-2a-infected MDCK cells suggested that the CPV-2a-induced apoptosis is caspase dependent involving extrinsic, intrinsic, and endoplasmic reticulum pathways. Increase in p53 and Bax/Bcl2 ratio was also observed in CPV-2a-infected cells. 相似文献
137.
Gosvami NN Feldmann M Peguiron J Moseler M Schirmeisen A Bennewitz R 《Physical review letters》2011,107(14):144303
Nanometer-scale friction measurements on a Au(111) surface have been performed at temperatures between 30 and 300?K by means of atomic force microscopy. Stable stick slip with atomic periodicity is observed at all temperatures, showing only weak dependence on temperature between 300 and 170?K. Below 170?K, friction increases with time and a distortion of the stick-slip characteristic is observed. Low friction and periodic stick slip can be reestablished by pulling the tip out of contact and subsequently restoring the contact. A comparison with molecular dynamics simulations indicates that plastic deformation within a growing gold junction leads to the observed frictional behavior at low temperatures. The regular stick slip with atomic periodicity observed at room temperature is the result of a dynamic equilibrium shape of the contact, as microscopic wear damage is observed to heal in the sliding contact. 相似文献
138.
Physics of Atomic Nuclei - Neutrino oscillation is an experimentally established phenomenon by which neutrinos undergo flavor transformations periodically as they propagate large enough distances.... 相似文献
139.
Hardeep Singh Tuli Ajay Kumar Seema Ramniwas Renuka Coudhary Diwakar Aggarwal Manoj Kumar Ujjawal Sharma Nidarshana Chaturvedi Parashar Shafiul Haque Katrin Sak 《Molecules (Basel, Switzerland)》2022,27(21)
Despite the immense therapeutic advances in the field of health sciences, cancer is still to be found among the global leading causes of morbidity and mortality. Ethnomedicinally, natural bioactive compounds isolated from various plant sources have been used for the treatment of several cancer types and have gained notable attention. Ferulic acid, a natural compound derived from various seeds, nuts, leaves, and fruits, exhibits a variety of pharmacological effects in cancer, including its proapoptotic, cell-cycle-arresting, anti-metastatic, and anti-inflammatory activities. This review study presents a thorough overview of the molecular targets and cellular signaling pathways modulated by ferulic acid in diverse malignancies, showing high potential for this phenolic acid to be developed as a candidate agent for novel anticancer therapeutics. In addition, current investigations to develop promising synergistic formulations are also discussed. 相似文献
140.