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131.
M. Nasim S. K. Tripathi S. B. Mishra B. L. Khandelwal 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):1019-1034
Abstract A series of phenol-substituted acyclic Schiff bases, 2,6-{RE(CH2) n N═C(CH3)}2-C6H2(4-CH3)(OH), (E = Te: R = C6H5, n = 2(L a), 3(L b); R = C6H4-4-OCH3, n = 2(L c), 3(L d); E = Se: R = C6H5, n = 2(L e), 3(L f)), of the type E2N2O have been synthesized by condensation of 2,6-diacetyl-4-methylphenol with arylchalcogenoalkylamines. This ligand framework is useful for designing molecular complexes with a variety of coordination modes depending upon the nature of the central metal atom. The reactivity of the tellurium-bearing macroacyclics ligands towards Zn(II), Cd(II), and Hg(II) has been examined. The ligands L a?L d with Zn(II) and Cd(II), and only L a and L b with Hg(II) form complexes of composition M2X4L, (X = Cl or Br), whereas L c and L d with Hg(II) give products of composition HgBr2L. The modes of ligand interaction with Zn(II) and Cd(II) are different than that with Hg(II). Following a multistep reaction involving abstraction of bridged Br atoms and subsequent addition of more ligand, the mercury complex, Hg2Br4L has been used for developing metallocyclic system of the type [Hg2Br2L2]2+. The latter has been found to encapsulate Zn(II) and Cd(II) to give multimetallic systems. 相似文献
132.
Mohammad Anary-Abbasinejad Hamidreza Dehghanpour Farashah Hossein Anaraki-Ardakani Nasim Shams 《合成通讯》2013,43(13):1877-1884
A new and efficient one-pot synthesis of polysubstituted pyrrole derivatives by three-component reaction of dialkyl acetylenedicarboxylates, triphenylphosphine, 2-aminothiazole or 2-aminobenzothiazole in the presence of arylglyoxals is described. The reactions were performed in dichloromethane at room temperature and neutral conditions and afforded good yields of products. 相似文献
133.
Harmon AM Lash MH Tishbi N Lent D Mintzer EA Uhrich KE 《Langmuir : the ACS journal of surfaces and colloids》2011,27(15):9131-9138
Surfactant amphiphilic macromolecules (AMs) were complexed with a 1:1 ratio of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE), either by a coevaporation (CE) or postaddition (PA) method, to form AM-lipid complexes with enhanced drug delivery applications. By characterizing the surfactant-lipid interactions, these heterogeneous drug delivery systems can be better controlled and engineered for optimal therapeutic outcomes. In this study, the physical interactions between DOPE:DOTAP liposomes and AM surfactants were investigated. Langmuir film balance and isothermal calorimetry studies showed cooperative intermolecular interactions between pure lipids and AM in monolayers and high thermostability of structure formed by the addition of AM micelles to DOTAP:DOPE vesicles in buffer solution respectively. Increasing the AM weight ratio in the complexes via the CE method led to complete vesicle solubilization--from lamellar aggregates, to a mixture of coexisting vesicles and micelles, to mixed micelles. Isothermal calorimetry evaluation of AM-lipid complexes shows that, at higher AM weight ratios, PA-produced complexes exhibit greater stability than complexes at lower AM weight ratios. Similar studies show that AM-lipid complexes produced by the CE methods display stronger interactions between AM-lipid components than complexes produced by the PA method. The results suggest that the PA method produces vesicles with AM molecules associated with its outer leaflet only (i.e., an AM-coated vesicle), while the CE method produces complexes ranging from mixed vesicles to mixed micelle in which the AM-lipid components are more intimately associated. These results will be helpful in the design of AM-lipid complexes as structurally defined, stable, and effective drug delivery systems. 相似文献
134.
Nasim Alem Rolf Erni Christian Kisielowski Marta D. Rossell Peter Hartel Bin Jiang Will Gannett A. Zettl 《固体物理学:研究快报》2011,5(8):295-297
Atomically thin hexagonal boron nitride (h‐BN) is investigated using aberration‐corrected ultra‐high resolution electron microscopy under 80 kV electron beam. This study focuses on the in situ formation, growth and migration of vacancies in h‐BN. This study also reveals interaction dynamics of edges and vacancies with adatoms and molecules under the electron beam. According to this investigation, boron monovacancies migrate through their second neighbor to reduce the surface energy of the membrane. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
135.
Prof. Dr. Lena Keller Dr. Emilia Oueis Dr. Amninder Kaur Dr. Nasim Safaei Dr. Susanne H. Kirsch Dr. Antonia P. Gunesch Dr. Sibylle Haid Dr. Ulfert Rand Prof. Dr. Luka Čičin-Šain Dr. Chengzhang Fu PD Dr. Joachim Wink Prof. Dr. Thomas Pietschmann Prof. Dr. Rolf Müller 《Angewandte Chemie (International ed. in English)》2023,62(6):e202214595
A new family of highly unusual sesquarterpenoids (persicamidines A–E) exhibiting significant antiviral activity was isolated from a newly discovered actinobacterial strain, Kibdelosporangium persicum sp. nov., collected from a hot desert in Iran. Extensive NMR analysis unraveled a hexacyclic terpenoid molecule with a modified sugar moiety on one side and a highly unusual isourea moiety fused to the terpenoid structure. The structures of the five analogues differed only in the aminoalkyl side chain attached to the isourea moiety. Persicamidines A–E showed potent activity against hCoV-229E and SARS-CoV-2 viruses in the nanomolar range together with very good selectivity indices, making persicamidines promising as starting points for drug development. 相似文献