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71.
Synthesis and Antimicrobial Activities of Novel Series of 3‐(4‐(2‐substituted thiazol‐4‐yl)phenyl)‐2‐(4‐methyl‐2‐substituted thiazol‐5‐yl)thiazolidin‐4‐one Derivatives
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Shivaji H. Shelke Pravin C. Mhaske Sachin Narkhade Vivek D. Bobade 《Journal of heterocyclic chemistry》2014,51(4):1151-1156
In the present investigation, a novel series of 3‐(4‐(2‐substituted thiazol‐4‐yl)phenyl)‐2‐(4‐methyl‐2‐substituted thiazol‐5‐yl)thiazolidin‐4‐one derivatives were synthesized by condensation of 2‐substituted‐4‐methylthiazole‐5‐carbaldehyde with 4‐(2‐substituted thiazol‐4‐yl)benzenamine followed by cyclo‐condensation with thioglycolic acid in toluene. All the newly synthesized compounds were characterized by spectral (IR, 1H NMR, 13C NMR, and Mass) methods. The title compounds were screened for quantitative antibacterial activity (minimal inhibitory concentration). All compounds 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h and 8a , 8b , 8c , 8d , 8e , 8f , 8g , 8h show moderate to good antimicrobial activity, whereas compounds ( 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h ) also show moderate antifungal activity. 相似文献
72.
Pravin L. Kotian 《Tetrahedron letters》2011,52(3):365-368
Imino sugar compound 3 was prepared by two alternative routes starting from ribose and d-serine. From d-serine (3R,4R,5R)-3,4-dihydroxy-5-(hydroxymethyl)-3-methylpyrrolidin-2-one was prepared in five steps in 50% overall yield, which was further converted into (2R,3R,4S)-2-(hydroxymethyl)-4-methylpyrrolidine-3,4-diol in three steps in 23% overall yield. 相似文献
73.
Lvov YM Pattekari P Zhang X Torchilin V 《Langmuir : the ACS journal of surfaces and colloids》2011,27(3):1212-1217
Aqueous nanocolloids of poorly soluble materials were produced via sonicated layer-by-layer (LbL) encapsulation with polycation / polyanion shells. Synergy of simultaneous breaking powder particles with ultrasonication and coating them with polycations allowed for the production of 150-200 nm diameter polyelectrolyte coated nanoparticles with sufficient surface electrical potential for colloidal stability. This technique increases water dispersibility of low soluble materials ranging from anticancer drugs to anticorrosion agents, dyes and inorganic salts. 相似文献
74.
Pravin V. ShindeAmol H. Kategaonkar Bapurao B. ShingateMurlidhar S. Shingare 《Tetrahedron letters》2011,52(22):2889-2892
In the present work, successful implementation of ultrasound irradiation for the rapid synthesis of α-hydroxy and α-amino phosphonates under solvent-free conditions is demonstrated. Use of a novel catalyst (i.e., camphor sulfonic acid) in combination with ultrasound technique is reported for the first time. Comparative study for the synthesis of α-hydroxy and α-amino phosphonates using conventional as well as ultrasonication method is discussed. 相似文献
75.
Julien P.A. Makongo Dinesh K. Misra James R. Salvador Nathan J. Takas Guoyu Wang Michael R. Shabetai Aditya Pant Pravin Paudel Ctirad Uher Kevin L. Stokes Pierre F.P. Poudeu 《Journal of solid state chemistry》2011,184(11):2948-2960
Bulk Zr0.25Hf075NiSn half-Heusler (HH) nanocomposites containing various mole fractions of full-Heusler (FH) inclusions were prepared by solid state reaction of pre-synthesized HH alloy with elemental Ni at 1073 K. The microstructures of spark plasma sintered specimens of the HH/FH nanocomposites were investigated using transmission electron microscopy and their thermoelectric properties were measured from 300 K to 775 K. The formation of coherent FH inclusions into the HH matrix arises from solid-state Ni diffusion into vacant sites of the HH structure. HH(1–y)/FH(y) composites with mole fraction of FH inclusions below the percolation threshold, y∼0.2, show increased electrical conductivity, reduced Seebeck coefficient and increased total thermal conductivity arising from gradual increase in the carrier concentration for composites. A drastic reduction (∼55%) in κl was observed for the composite with y=0.6 and is attributed to enhanced phonon scattering due to mass fluctuations between FH and HH, and high density of HH/FH interfaces. 相似文献
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78.
Pravin G. Bhuta 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1964,15(6):647-652
Zusammenfassung Für einen beidseitig eingespannten schlanken Stab, dessen Enden sich auf einem Kreis verschieben können, wird die exakte Lösung entwickelt. Die Reaktionen sowie die elastische Linie lassen sich mit Hilfe von elliptischen Integralen erster und zweiter Gattung bestimmen. Ein numerisches Beispiel zeigt die Anwendung der behandelten Methode, die bei der Konstruktion gewisser drehbarer Einspannung von Interesse ist. 相似文献
79.
80.
An ultrahigh-molecular-weight polyethylene material covering a range of crystallinity from 42 to 79% increased in calorimetric crystallinity as a result of chain scission following ionizing irradiation. Carbonyl was formed by a diffusion-limited reaction of oxygen with long-lived free radicals. Trans-vinylene production was linear with radiation dose and was highest for the sample of highest crystallinity but was not sensitive to environment. 相似文献