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41.
P. V. Raja Shekar D. Nagaraju V. Ganesh K. Kishan Rao 《Crystal Research and Technology》2009,44(6):652-656
Single crystals of Sr(NO3)2, Ba(NO3)2 and Pb(NO3)2 are grown from their aqueous solutions at a constant temperature of 35 °C by slow evaporation technique. Crystals of size 8 to 10 mm along one edge are obtained in a period of 10 days. Chemical etching technique has been employed to study the dislocations in these crystals. The dislocations are randomly distributed and the dislocation density is about 104 to 105 /cm2. Microhardness studies are made on as–grown (111) faces of these crystals upto a load of 100 g. The hardness of the crystals increases with an increase in load and thereafter it becomes independent of the applied load. These results are discussed on the basis of reverse indentation size effect. Meyer index number n for these crystals is estimated at both low and high load regions. An analysis of hardness data of these crystals as well as some other cubic crystals like alums and alkali halates are discussed using Gilman–Chin parameter Hv/C44, where Hv is the microhardness and C44 is the shear constant. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
42.
Nagaraju Kerru Sandeep V.H.S. Bhaskaruni Lalitha Gummidi Surya Narayana Maddila Surjyakanta Rana Parvesh Singh Sreekantha B. Jonnalagadda 《应用有机金属化学》2019,33(5)
An efficient approach for the synthesis of 10 novel pyrazole‐based 1,2,4‐triazolidin‐3‐one derivatives catalyzed by ZnO‐loaded ZrO2 as heterogeneous catalyst with ethanol as solvent is described. The structure of the mixed metal oxide catalyst was characterized by various instrumental techniques (scanning electron microscopy, transmission electron microscopy, X‐ray diffraction and Brunauer–Emmett–Teller). In smooth reactions, products were accomplished in excellent yields (90–94%) with short reaction times (≈ 45 min). ZnO/ZrO2 catalyst exhibited good recyclability. The catalyst is reused six times without any noticeable loss of activity. The major advantages of this method are operational simplicity, mild conditions, simple work‐up procedure and broad functional group tolerance. 相似文献
43.
Dongamanti Ashok M. Ram Reddy Katta Ramakrishna Nalaparaju Nagaraju Ravinder Dharavath Madderla Sarasija 《Journal of heterocyclic chemistry》2020,57(6):2528-2534
Herein, we reported a series of new 2-(5-methyl-1-aryl-1H-1,2,3-triazol-4-yl)imidazo[1,2-a]pyridines by using iodine and NH4OAc in good yields. The structures of the titled compounds were characterized by the elemental analysis, 1H NMR, 13C NMR, IR, and mass spectral analysis. All the titled compounds were screened for their in vitro antibacterial and antifungal activities by using streptomycin and Nystatin as standard drugs. The compounds 3k , 3l , 3g , and 3c exhibited potent activity against the tested bacterial strains and 3k , 3l , and 3c exhibited potent activity against the tested fungal strains than the reference drugs. 相似文献
44.
S.P. Vinay Udayabhanu H.N. Sumedha G. Nagaraju S. Harishkumar N. Chandrasekhar 《应用有机金属化学》2020,34(10):e5830
Silver oxide nanoparticles (Ag2O NPs) were prepared using cantaloupe (Cucumis melo) seeds as a fuel by employing a green synthesis method. The prepared Ag2O NPs were investigated using powder X-ray diffraction (PXRD), UV–visible spectrum, Fourier transform infrared analysis, transmission electron microscopy (TEM), scanning electron microscopy (SEM) with energy-dispersive spectroscopy, and photoluminescence studies. PXRD data reveal the establishment of cubic crystal structure of Ag2O NPs. According to SEM and TEM results, the morphology of the prepared NPs was agglomerated and spherical. The photodegradation activity of the prepared Ag2O NPs over methylene blue dye was promising under visible light irradiation. Furthermore, the antimicrobial assay of the synthesized Ag2O NPs was carried out by the disc diffusion method against Gram-positive and Gram-negative microbial strains. 相似文献
45.
Radha Rani Chinthaparthi Chandra Sekhar Reddy Gangireddy Veeranarayana Reddy Mudumala Mohan Gundluru Nagaraju Chamarthi Suresh Reddy Cirandur 《Tetrahedron letters》2013
An efficient and simple protocol is reported for the synthesis of a new class of 1-substituted-octahydro-[1,3,2]diazaphospholo[1,5-a]pyridine-1-oxides in good to excellent yield (88–95%) via Michaelis–Arbuzov rearrangement. Condensation of diamido phosphite with various halides at 60 °C using CeCl3·7H2O as a highly efficient catalyst afforded the products within a short period of reaction time. This procedure is mild, efficient, and non-toxic and stability of the catalyst is the merit of this process. Therefore, this protocol being environmentally benign and efficient, serves as an alternative procedure for the preparation of the title compounds. 相似文献
46.
Sanjay Singh Rina Mahato Pragya Sharma Naveen Yadav Nagaraju Vodnala Dr. Chinmoy Kumar Hazra 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(14):e202104545
This work describes a mild and robust double hydroarylation strategy for the synthesis of symmetrical /unsymmetrical diaryl- and triarylmethanes in excellent yields using Lambert salt (0.2–1.0 mol%). Despite the anticipated challenges associated with controlling selective product formation, unsymmetrical diaryl- and triarylmethanes products are obtained unprecedentedly. A highly efficient gram scale reaction has also been reported (TON for symmetrical product=475 and for unsymmetrical product=390). The synthetic utility of the methodology is demonstrated by the preparation of several unexplored diaryl- and triarylmethane-based biologically relevant molecules, such as arundine, vibrindole A, turbomycin B, and certain anti-inflammatory agents. A total synthesis of an anti-breast-cancer agent is also demonstrated. Control experiments, Hammett analysis, HRMS and GC-MS studies reveal the reaction intermediates and reaction mechanism. 相似文献
47.
Sakkani Nagaraju Kota Sathish Neeli Satyanarayana Banoth Paplal Dhurke Kashinath 《Journal of heterocyclic chemistry》2020,57(1):469-476
Catalyst-free synthesis of the isoxazole-spirooxindole-tetrahydrothiophene hybrids is reported. Formation of 1,4-thia-Michael and intramolecular aldol reactions were observed (instead of 1,6-thia-Michael followed by vinylogous Henry reactions) in a regioselective fashion to give new isoxazole-spirooxindole-tetrahydrothiophene hybrids with excellent yields. 相似文献
48.
Murthy JN Nagaraju M Sastry GM Rao AR Sastry GN 《Journal of computer-aided molecular design》2005,19(12):857-870
Summary This study sheds new light on the role of acidic residues present in the active site cavity of human aromatase. Eight acidic
residues (E129, D222, E245, E302, D309, E379, D380 and D476) lining the cavity are identified and studied using comparative
modeling, docking, molecular dynamics as well as statistical techniques. The structural environment of these acidic residues
is studied to assess the stability of the corresponding carboxylate anions. Results indicate that the environment of the residues
E245, E302 and D222 is most suitable for carboxylate ion formation in the uncomplexed form. However, the stability of D309,
D222 and D476 anions is seen to increase on complexation to steroidal substrates. In particular, the interaction between D309
and T310, which assists proton transfer, is found to be formed following androgen/nor-androgen complexation. The residue D309
is found to be clamped in the presence of substrate which is not observed in the case of the other residues although they
exhibit changes in properties following substrate binding. Information entropic analysis indicates that the residues D309,
D222 and D476 have more conformational flexibility compared to E302 and E245 prior to substrate binding. Interaction similar
to that between D476 and D309, which is expected to assist androgen aromatization, is proposed between E302 and E245. The
inhibition of aromatase activity by 4-hydroxy androstenedione (formestane) is attributed to a critical hydrogen bond formation
between the hydroxy moiety and T310/D309 as well as the large distance from D476. The results corroborate well with earlier
site directed mutagenesis studies. 相似文献
49.
A Convenient and Facile Hantzsch Synthesis of Aryl Imidazo[1,2‐b]Isoxazolyl‐N‐aryl Thiazol Amines 下载免费PDF全文
E. Rajanarendar K. Thirupathaiah S. Ramakrishna D. Nagaraju 《Journal of heterocyclic chemistry》2016,53(6):1983-1989
The Hantzsch synthesis of novel aryl imidazo[1,2‐b]isoxazolyl‐N‐aryl thiazol amines 5 analogues were described. Reaction of 3‐aminoisoxazole 1 with substituted phenacyl bromides 2 in dry ethanol afforded the corresponding 6‐methyl‐3‐arylimidazo[1,2‐b]isoxazoles 3 in good yields. Compounds 3 on reaction with chloroacetyl chloride in 1,4‐dioxane furnished the corresponding 2‐chloro‐1‐(6‐methyl‐3‐arylimidazo[1,2‐b]isoxazol‐2‐yl)ethanones 4 . Compounds 4 on heating with N‐aryl thioureas in an oil bath underwent cyclization to afford the title compounds viz., imidazo[1,2‐b]isoxazolyl‐N‐aryl thiazol amines 5 in moderate to good yields by Hantzsch synthesis. 相似文献
50.
Gomathi Devi Lakshmipathi Naik Nagaraju Kottam Girish Kumar Shivashankar 《中国化学》2010,28(11):2151-2161
Mn2+ ion was doped into the TiO2 matrix and its photocatalytic activity was evaluated for the degradation of a mono azo dye methyl orange (MO) and a di‐azo dye brilliant yellow (BY) under UV/solar light. X‐ray diffraction results revealed the phase transformation from anatase to rutile due to the inclusion of Mn2+ ion into the TiO2 matrix. All the doped catalysts showed a red shift in the band gap to the visible region. The degradation reaction of the dyes was found to be dependent on its structure. It was found that mono azo dye degrades faster than di azo dye under UV/solar light. The rate constant under identical conditions calculated for the degradation of MO is 2.4 times (under UV light) and 4.5 times (under solar light) higher compared to BY. Among the photocatalysts studied, Mn2+(0.06 at.%)‐TiO2 showed higher activity under both UV and solar light illumination. The synergestic effect in the bicrystalline framework of anatase and rutile effectively suppresses the charge carrier recombination and enhances the photocatalytic activity. The degradation reaction was followed by UV‐visible spectroscopy and the photoproducts formed were analyzed by GC‐MS techniques. 相似文献