Synthesis Of Macrocyclic Ligands Research Articles

Front Cover: Siloxane Coordination Revisited: Si−O Bond Character, Reactivity and Magnificent Molecular Shapes (Eur. J. Inorg. Chem. 29/2021)

The Front Cover shows some of the most beautiful “blooms” as well as “exotic birds” obtained in the course of the coordination of siloxanes to metal and non-metal cations. The accompanying review article summarizes the dynamic development of siloxane coordination chemistry in recent years and discusses the special properties of Si−O bonding. The elusive Si-O bond character on the one hand limits possible coordination, but on the other hand, it has promoted research around siloxane bonding and activation. This has led to new preparative possibilities in the synthesis of macrocyclic ligands and their complexes. Credit (cover background): pixabay. More information can be found in the Review by F. Dankert and C. von Hänisch.

In situ synthesis, characterization, bovine serum albumin (BSA) binding studies of FeII/CoII/NiII complexes derived from a new double bis-triazole macrocyclic ligand

The design and synthesis of macrocyclic ligands has become a hot research field of coordination chemistry for their novel structures and intriguing properties. Starting from bis (5-amion-1H-1,2,4-triazole) ligand (L1), three macrocyclic complexes with a novel double bis-triazole macrocyclic ligand (L2), [MCl2L2] (M = Fe, Co, Ni), were designed and synthesized by in situ reaction. In the process of reaction, metal ions played a key role for contributing to the formation of novel macrocyclic structures. The molecular structures of complexes were characterized by single-crystal X-ray diffraction, and the detailed description of synthesis is presented in this paper. The fluorescence quenching spectra and UV–vis spectra were used to study the interaction of complexes with bovine serum albumin (BSA). The results showed that the fluorescence quenching of BSA by these complexes was the presence of static quenching.

Spectral, Electrochemical, Fluorescence, Kinetic and Anti-microbial Studies of Acyclic Schiff-base Gadolinium(III) Complexes

Centre for Advanced Studies in Botany, University of Madras, Guindy Maraimalai Campus, Chennai 600 025, IndiaReceived June 5, 2012, Accepted August 1, 2012A new series of acyclic mononuclear gadolinium(III) complexes have been prepared by Schiff-base con-densation derived from 5-methylsalicylaldehyde, diethylenetriamine, tris(2-aminoethyl) amine, triethylene-tetramine, N,N-bis(3-aminopropyl)ethylene diamine, N,N-bis(aminopropyl) piperazine, and gadolinium nitrate.All the complexes were characterized by elemental and spectral analyses. Electronic spectra of the complexesshow azomethine (CH=N) within the range of 410-420 nm. The fluorescence efficiency of Gd(III) ion in thecavity was completely quenched by the higher chain length ligands. Electrochemical studies of the complexesshow irreversible one electron reduction process around −2.15 to −1.60 V The reduction potential ofgadolinium(III) complexes shifts towards anodic directions respectively upon increasing the chain length. Thecatalytic activity of the gadolinium(III) complexes on the hydrolysis of 4-nitrophenylphosphate was determin-ed. All gadolinium(III) complexes were screened for antibacterial activity. Key Words : Schiff-base ligands, Gadolinium(III) complexes, Fluorescence, Kinetic, Anti-microbialIntroductionIn the past decade, a great attention has been devoted tothe design and the synthesis of macrocyclic ligands and theirlanthanide complexes are a fascinating area of research,owing to their importance in basic and applied chemistry. Inparticular, acyclic Schiff bases have successfully been pro-posed as excellent systems in the formation of mono, homo,hetero nuclear lanthanide complexes.

Synthesis and efficacy of divalent metal complexes with ligand derived from 2,2-dihydroxyindane and aromatic diaminopyridines against fungi

The synthesis of macrocyclic ligands and their metal complexes is a fast developing area of research in bioinorganic and inorganic chemistry as witnessed by biologically important systems. A new series of divalent copper, nickel, iron and cobalt complexes has been prepared templately with 2,2-dihydroxyindane-1,3-dione and isomeric diaminopyridines and efficacy of these complexes is studied against Alternaria alternata and Fusarium oxysporum. The complexes have been characterized by the aid of elemental analyses, molar conductance, electronic spectra, ESR, magnetic measurements and IR spectral data has been collected. The complexes are proposed to be distorted octahedral. The value of molar conductance (11–13 Ω −1 cm 2 mol −1) indicates them to be non-electrolytes. The fungicidal properties of these complexes has been compared with the standard indofil M-45 and bavistin. Some of the complexes have been found to be anti-fungal in nature.

Synthesis of Diquinolineno[1,3,7,9]Tetraazacyclododecine-7, 15 (14H, 16H)-Dibenzene, and DNA Binding Studies of Macrocyclic Co(II), Cu(II) Complexes: As New Class of Antimicrobial Agent

The synthesis of macrocyclic ligand, diquinolineno[1,3,7,9]tetraazacyclododecine-7, 15 (14H, 16H)-dibenzene(L), is described. The metal complexes of the type [MLX2], where (M = Co(II) (1), Cu(II) (2) and X = (Cl), have been synthesized by the reaction of ligand(L) with the corresponding metal salts, and characterized by elemental analysis, FT-IR, 1H-NMR and electronic spectra. The binding property of the complexes with CT-DNA was studied by absorption spectra, viscosity measurements, as well as thermal denaturation studies. The absorption spectral results indicate that the complexes (1) and (2) are binds with base pairs of DNA. The intrinsic binding constant Kb had the value 3.8 × 104M −1 for (1) and 3.3 × 104 M−1 for (2), respectively, in 5 mM Tris-HCl/50 mM NaCl buffer at pH 7.2. The viscosity measurement results show the viscosity of sonicated rod-like DNA fragments increased when the complex were added to the solution of calf thymus-DNA. The synthesized ligand and its metal complexes have been screened for antibacterial and antifungal activities.

Synthesis of macrocyclic ligands incorporating sulfur and furan subunits

Abstract Polyammonium macrocycles containing sulfur and furan units in the macrocyclic ring have been synthesized and studied for ATPase activity. The synthetic methodology involved using tosyl protection for the amines and the formation of macrocyclic Lactams, followed by reduction using borane in THF. Deprotection of the tosylated forms of the macrocycle was accomplished using sodium in butanol for the furan macrocycles, and HBr in HOAc for the sulfur containing macrocycle. The macrocycles were found to be poor catalysts for ATP hydrolysis compared to other similar polyammonium macrocycles.

ChemInform Abstract: Design and Synthesis of Macrocyclic Ligands and Their Complexes of Lanthanoids and Actinoids

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Design and Synthesis of Macrocyclic Ligands and Their Complexes of Lanthanides and Actinides

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDesign and Synthesis of Macrocyclic Ligands and Their Complexes of Lanthanides and ActinidesV. AlexanderCite this: Chem. Rev. 1995, 95, 2, 273–342Publication Date (Print):March 1, 1995Publication History Published online1 May 2002Published inissue 1 March 1995https://doi.org/10.1021/cr00034a002RIGHTS & PERMISSIONSArticle Views6301Altmetric-Citations661LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (11 MB) Get e-Alerts Get e-Alerts

The Synthesis of Three New Macrocyclic Ligands and Preparation of Some of Their Cationic Complexes

Abstract In this study the synthesis of macrocyclic ligands 15,21-dinitro-2,5,8,ll-tetraoxatricyclo(17,4,0,012′17) tricosa-1 (23),12,14,16,19,21-hexaene-3,10-dione (I); 18,24-dinitro-2,5,8,1l,14-pentaoxatricyclo(20,4,0,015,20) hexacosa-l(26),15, 17,19,22,24-hexaene-3,13-dione (II) and 15,21-di-t-butyl-2,5,8,11-tetraoxatricyclo(17,4,0,012,17) tricosa-1(23),12,14,16, 19,21-hexaene-3,10-dione (III) are described. Attemption of the preparation of their complexes in crystalline form with NaClO4.H2O, KC1O4, and Ba(C1O4)2.3H2O are discussed.

Proton-ionizable crown compounds. 11. Synthesis of macrocyclic ligands containing two sulfonamide groups and chloro substituents or pyridine subcyclic units and a preliminary study of cation transport by three of these ligands

Five new macrocyclic ligands each containing two sulfonamide groups have been prepared. Three of these compounds contain one or two chloro substituents and the other two have one or two pyridine subcyclic units. A seventeen-membered ring ligand (4) was found to be an excellent transport agent for all alkali metal cations in a water-methylene chloride-water bulk liquid membrane system when the pH of the source phase was 13 or higher. The chlorine-substituted analog (5) was a poor transport agent for the alkali metal cations possibly because the chlorine atom blocked entry to the macrocycle cavity. An open-chain analog containing two sulfonamide groups was particularly effective in transporting cesium ions.

The template synthesis and characterization of hexaaza 18-membered macrocyclic complexes of cerium(III), praseodymium(III) and neodymium(III) nitrates

We have previously described the preparation and characterization of heavier trivalent lanthanide (Tb to Lu) complexes containing 14-membered quadridentate macrocyclic ligands [ 11. The lighter lanthanide ions (La to Gd) have been found to be ineffective as templates for the synthesis of this macrocycle. The important factor which must be taken into account in the planning of the synthesis of macrocyclic compounds with the aid of metal ion is the ratio of cation diameter to ligand cavity size. The cavity of 1Cmembered macrocycle is too small to enclose the lighter lanthanides. It was therefore interesting to investigate the template action of these ions in the synthesis of macrocyclic ligands with greater ring size. We found that the lanthanum ion may act as a template for the synthesis of 18-membered hexaaza sexidentate macrocyclic compounds [2, 31. The formation of the lanthanide complexes of some macrocyclic Schiff bases has recently been reported [4,5] . This paper reports the preparation and characterization of Ce(III), Pr(II1) and Nd(III) macrocyclic complexes derived from 2,6-diacetylpyridine and o-phenylenediamine. The complexes of 2,7,13,18-tetramethyl4,5:15, 16dibenzo-3,6,14,17,23,24-hexaazatricyclo[l7.3.1 l.81’2]fetrakoza-1(23),2,4,6,8,lO,l2(24),l3,15,l7,l9, 21 dodecaene ligand (L) have been prepared by

Synthesis of macrocyclic ligands containing the indole ring system

2,7-Diformyl-3-methyl-4,6-dimethoxyindole (6) has been synthesized and converted by metal template reactions into the macrocyclic complexes (10–12).