• Title/Summary/Keyword: Macrocyclic

Search Result 233, Processing Time 0.031 seconds

Template Synthesis and Characterization of Copper(Ⅱ) Complexes of a Polyaza Non-Macrocyclic or a Bis(macrocyclic) Ligand

  • 강신걸;유기석;정수경;김창수
    • Bulletin of the Korean Chemical Society
    • /
    • v.17 no.4
    • /
    • pp.331-334
    • /
    • 1996
  • New copper(Ⅱ) complex of the pentaaza non-macrocyclic ligand 1-(2-aminoethyl)-3-(N-{2-aminoethyl}aminomethyl)-1,3-diazacyclohexane (2) and a dinuclear copper(Ⅱ) compex of the bis(macrocyclic) ligand 3, in which two 1,5,8,10,12,15-hexaazabicyclo[11.3.11.5]heptadecane subunits are linked together by an ethylene chain through the uncoordinated nitrogen (N10) atoms, have been prepared selectively by the reaction of the metal ion, 1,4,8-triazaoctane, ethylenediamine, and formaldehyde. The dinuclear complex [Cu2(3)]4+ has been also prepared by the reaction of [Cu(2)]2+ with ethylenediamine and formaldehyde. The reaction products largely depend on the molar ratio of the reactants employed. The mononuclear complex or each macrocyclic subunit of the dinuclear complex contains one 1,3-diazacyclohexane ring and has a square-planar geometry with a 5-6-5 or 5-6-5-6 chelate ring sequence. In acidic solution, the copper(Ⅱ) complex of 2 dissociates more slowly than those of other related non-cyclic polyamines.

In vivo Imaging Biodistribution Profile of a New Macrocyclic Gadolinium Chelate as a Highly Stable Multifunctional MRI Contrast Agent

  • Sung, Bo Kyung;Jo, Yeong Woo;Chang, Yongmin
    • Investigative Magnetic Resonance Imaging
    • /
    • v.23 no.1
    • /
    • pp.34-37
    • /
    • 2019
  • Gadolinium contrast agents (CAs) are integral components of clinical magnetic resonance imaging (MRI). However, safety concerns have arisen regarding the use of gadolinium CAs, due to their association with nephrogenic systemic fibrosis (NSF). Furthermore, recently the long-term retention of $Gd^{3+}-based$ CAs in brains patients with normal renal function raised another possible safety issue. The safety concerns of $Gd^{3+}-based$ CAs have been based on the ligand structure of $Gd^{3+}-based$ CAs, and findings that $Gd^{3+}-based$ CAs with linear ligand structures showed much higher incidences of NSF and brain retention of CAs than $Gd^{3+}-based$ CAs with macrocyclic ligand structure. In the current study, we report the in vivo biodistribution profile of a new highly stable multifunctional $Gd^{3+}-based$ CA, with macrocyclic ligand structure (HNP-2006). MR imaging using HNP-2006 demonstrated a significant contrast enhancement in many different organs. Furthermore, the contrast enhanced tumor imaging using HNP-2006 confirmed that this new macrocyclic CA can be used for detecting tumor in the central nervous system. Therefore, this new multifunctional HNP-2006 with macrocyclic ligand structure shows great promise for whole-body clinical application.

Resin Synthesis of Adsorbent Uranium(VI) Ion using 1-Aza-18-Crown-6 (1-Aza-18-Crown-6를 이용한 우라늄(VI) 이온 흡착제 수지 합성)

  • Kim, Sun-Hwa;Kim, Hae-Jin
    • Journal of environmental and Sanitary engineering
    • /
    • v.21 no.4 s.62
    • /
    • pp.49-60
    • /
    • 2006
  • The ion exchange resins have been synthesized from chlormethyl styrene - 1,4 - divinylbenzene(DVB) with 1%, 2%, 4% and 8%-crosslinking and 1-aza-18-crown-6 macrocyclic ligand by copolymerization method. Content of chlorine in styrene-DVB copolymer was decreased as crosslink increased and it is because as crosslink increased 1%, 2%, 4% and 8% DVB content increased and crosslink density increased and cavity was reduced. Functional group of resin almost disappeared as C-C1 peak around $700cm^{-1}$ was substituted with 1-aza-18-C-6 macrocyclic ligand and new peak of C-N around $1020cm^{-1}$ appeared, so it was confirmed that styrene-DVB copolymer and ligand were compounded. As crosslink increased in the analysis of element contents, it resulted in the reduction of nitrogen content and it is because as crosslink increased, it led to the reduction of chlorine content in the process of substitution reaction and it affected macrocyclic ligand substituted. Thermo analysis curve of functional synthetic resin decomposed three part of 1-aza-18-C-6, styrene, and DVB. Form of functional synthetic resin showed distortion of its particles as macrocyclic ligand was introduced to styrene-DVB copolymer and hydrogen of ligand caused substitution with chlorine element of styrene molecule.

Antifungal Activities of Biorelevant Complexes of Copper(II) with Biosensitive Macrocyclic Ligands

  • Raman N.;Joseph J.;Velan A. Senthil Kumara;Pothiraj C.
    • Mycobiology
    • /
    • v.34 no.4
    • /
    • pp.214-218
    • /
    • 2006
  • Four copper(II) complexes have been prepared using macrocyclic ligands. The macrocyclic ligands have been synthesized by the condensation reaction of diethyl phthalate with Schiff bases derived from o-phenylene diamine and Knoevenagel condensed ${\beta}-ketoanilides$ (obtained by the condensation of acetoacetanilide and substituted benzaldehydes). The ligands and copper complexes have been characterized on the basis of Microanalytical, Mass, UV-Vis., IR and CV spectral studies, as well as conductivity data. On the basis of spectral studies, a square-planar geometry for the copper complexes has been proposed. The in vitro antifungal activities of the compounds were tested against fungi such as Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans. All the synthesized copper complexes showed stronger antifungal activities than free ligands. The minimum inhibitory concentrations (MIC) of the copper complexes were found in the range of $8{\sim}28\;{\mu}g/ml$. These compounds represent a novel class of metal-based antifungal agents which provide opportunities for a large number of synthetic variations for modulation of the activities.

Designing and Synthesis of Antifungal Active Macrocyclic Ligand and Its Complexes Derived from Diethylphthalate and Benzidine

  • Raman, N.;Parameswari, S.
    • Mycobiology
    • /
    • v.35 no.2
    • /
    • pp.65-68
    • /
    • 2007
  • Three novel complexes of Cu(II), Co(II) and Zn(II) using a macrocyclic ligand derived by the condensation of diethylphthalate and benzidine have been designed, synthesized and characterized by UV-Vis., IR, Mass and Elemental analyses data in order to find out their antifungal activities. The stoichiometry of the complexes has been found to be 1:1 (Metal: Ligand). The analytical data indicate that the complexes exhibit square-planar geometry. The antifungal activity of the macrocyclic ligand and its metal complexes has been screened in vitro against fungi such as Aspergillus niger, A. flavus, Trichoderma harizanum, T. viridae and Rhizoctonia solani.

Studies on Reactions of a Nickel Complex of a New Completely Conjugated Macrocyclic Ligand

  • Park, Young-Ae W.;Oh, Soon-Song
    • Bulletin of the Korean Chemical Society
    • /
    • v.8 no.6
    • /
    • pp.476-479
    • /
    • 1987
  • The macrocyclic nickel complex of the molecular formula[Ni($C_{32}H_{26}N_4$)] has been synthesized from the template condensation reaction between 1-benzoylacetone and o-phenylenediamine in the presence of nickel acetate. Protonation and deuterium exchange reactions of the demetallated macrocyclic ligand and the nickel complex have been carried out. The infrared, electronic and proton magnetic resonance spectral data of both compounds are compared and discussed; protonation of the macrocyclic ligand take place at the nitrogen atoms and all the amine protons undergo very rapid deuterium exchange while the methine protons undergo very slow exchange. On the other hand, protonation of the nickel complex occurs at the nitrogen atoms and only amine protons undergo rapid deuterium exchange. Protonation and deprotonation of the nickel complexes proceed reversibly.

Template Synthesis and Characterization of Binuclear Nickel(Ⅱ) and Copper(Ⅱ) Complexes of Double-ring Macrocyclic Ligands

  • Shin-Geol Kang;Soo-Kyung Jung;Jae Keun Kweon
    • Bulletin of the Korean Chemical Society
    • /
    • v.12 no.2
    • /
    • pp.219-224
    • /
    • 1991
  • New binuclear Ni(Ⅱ) and Cu(Ⅱ) complexes with various alkyl derivatives of 1,2-bis(1,3,6,8,10,13-hexaaza-1-cyclotetradecyl) ethane, in which two fully saturated 14-membered hexaaza macrocyclic subunits are linked together by an ethylene chain, have been synthesized by the one step template condensations of formaldehyde with ethylenediamine and appropriate primary alkyl amines in the presence of the metal ions. Each macrocyclic subunit of the double-ring macrocyclic complexes contains one alkyl pendant arm and has a square planar geometry with a 5-6-5-6 chelate ring sequence. The visible spectra and oxidation properties indicate that the metal-metal interaction of the binuclear complexes are not significant. Synthesis, characterization, and the properties of the complexes are presented.