Pentaaza Macrocyclic Ligands Research Articles

Insight on spectral, thermal and biological behaviour of some Cu(II) complexes with saturated pentaazamacrocyclic ligands bearing amino acid residues

A novel series of Cu(II) complexes with formula M(HLn)(ClO4)2·mH2O [HLn: 13-membered pentaazamacrocyclic ligand resulted from condensation of N,N′-bis(2-aminoethyl)ethane-1,2-diamine, l-tyrosine (HL1)/l-tryptophan (HL2)/l-phenylalanine (HL3) and formaldehyde] were synthesized by one-pot method. Techniques such as ESI–MS, IR, UV–Vis and EPR spectroscopy provided data characterizing the complexes as mononuclear species. The course of thermal decomposition was followed using TG/DSC–MS analysis in air atmosphere. The TG curves showed a gradual decomposition in several stages that comprise dehydration, decomposition of perchlorate ions as well as fragmentation and oxidative degradation of the organic part. The intermediates formed after first stage of water elimination are stable on 40, 15 and 80 °C interval for complexes (1), (2) and (3), respectively. The compounds were tested on the eukaryotic unicellular organism Saccharomyces cerevisiae, showing variable actions in terms of toxicity, cellular uptake and capacity to alleviate growth defects associated with Cu, Zn-superoxide dismutase (SOD1) depletion.

Insight on thermal, spectral, magnetic and biological behaviour of new Ni(II), Cu(II) and Zn(II) complexes with a pentaazamacrocyclic ligand derived from nicotinamide

New species of type [MLCl2]·nH2O (M:Ni, n = 0; M:Cu, n = 1 and M:Zn, n = 0; L: 1,3,5,8,11-pentaazacyclotridecane-3-yl-(pyrid-3-yl)-methanone resulted by N,N’-bis(2-aminoethyl)ethane-1,2-diamine, nicotinamide and formaldehyde) were synthesised by one-pot condensation. Chemical analysis, ESI–MS, IR, 1H NMR, 13C NMR, UV–Vis–NIR, EPR spectroscopy as well as magnetic data at room temperature were used in order to characterise the compounds. The data provided by IR, ESI–MS and NMR spectra are consistent with the macrocycle formation. Electronic spectra indicate that both Ni(II) and Cu(II) adopt an octahedral stereochemistry data furthermore confirmed by magnetic moments and EPR spectrum at room temperature. The electrochemical behaviour of the compounds was investigated by cyclic voltammetry. Processes as water and chloride elimination as well as oxidative degradation of the macrocyclic ligand were observed by simultaneously TG–DTA measurements. The final residue as the most stable metallic oxide was identified by X-ray powder diffraction. The compound [CuLCl2]·H2O (2) exhibits fungicidal and anti-biofilm activity on Candida albicans strains. The complexes exhibit a low cytotoxicity on HEp 2 cells, except for Cu(II) species that induce the cellular cycle arrest in the G2/M phase.

Transition metal complexes of a new 15-membered [N5] penta-azamacrocyclic ligand with their spectral and anticancer studies

Novel penta-azamacrocyclic 15-membered [N5] ligand [L] i.e. 1,5,8,12-tetetraaza-3,4: 9,10-dibenzo-6-ethyl-7-methyl-1,12-(2,6-pyrido)cyclopentadecan-5,7 diene-2,11-dione and its transition metal complexes with Co(II), Ni(II), Cu(II), Ru(III) and Pd(II) have been synthesized and structurally characterized by elemental analysis, spectral, thermal as well as magnetic and molar conductivity measurements. On basis of IR, MS, UV–Vis 1H NMR and EPR spectral studies an octahedral geometry has been proposed for all complexes except Co(II), Cu(II) nitrate complexes and Pd(II) chloride complex that adopt tetrahedral, square pyramidal and square planar geometries, respectively. The antitumor activity of the synthesized ligand and some complexes against human breast cancer cell lines (MCF-7) and human hepatocarcinoma cell lines (HepG2) has been studied. The complexes (IC50=2.04–9.7, 2.5–3.7μg/mL) showed potent antitumor activity comparable with their ligand (IC50=11.7, 3.45μg/mL) against the above mentioned cell lines, respectively. The results evidently show that the activity of the ligand becomes more pronounced and significant when coordinated to the metal ion.

Comparative study of carbon paste electrodes modified by new pentaaza macrocyclic ligands and gold nanoparticles embedded in three-dimensional sol–gel network for determination of trace amounts of Ag(I)

Two new Ag(I) chemically modified carbon paste electrodes were prepared with comparative potentiometric study of 1,3,6,10,13-pentaaza-2,14-(2,6-pyridyl)-cyclotetradecane-4,12-dione (PPCT) and 1,3,6,9,11,12-pentaaza-2,13-(2,6-pyridyle)-bicycle[2,2,9]pentadecane-4,11-dione (PPBP) as ionophore. These sensors have been modified with sol–gel–Au nanoparticles to obtain a wide concentration range for potentiometric determination of Ag(I) in aqueous solutions. The sensors exhibit significantly enhanced selectivity toward Ag(I) ions over a wide concentration range of 4.0 × 10−9–2.2 × 10−2 and 2.2 × 10−7–2.0 × 10−2 mol L−1 with a lower detection limit of 2.5 × 10−9 and 2.0 × 10−7 mol L−1 for PPCT and PPBP modified electrodes respectively. The electrodes are highly selective to Ag(I) ions over a large number of mono, bi, and tri-valent cations. These electrodes were successfully used as indicator electrode for potentiometric determination of silver in sulphadiazine (burning cream) and radiological film.

ChemInform Abstract: Synthesis, Characterization and Solution 113Cd NMR Analysis of Cd(II) 1,4,7,10,13-Pentaazacyclopentadecane Complexes

Two new cadmium(II) complexes of the macrocyclic ligand, 1,4,7,10,13-pentaazacyclopentadecane 5 , have been prepared and characterized. The crystal structure of dichlorocadmium(II) complex 3 was determined and reveals that the Cd(II) is coordinated in a pentagonal bipyramidal array of the five nitrogens of the macrocyclic ring and capped by two trans -chloro ligands. Crystal data for Cd(C 10 H 25 N 5 )Cl 2 –0.5H 2 O are as follows: monoclinic at 20 °C, space group C2/c−C 6 2h (No. 15) with a =22.165(5) A, b =11.439(3) A, c =14.6788(4) A, β =118.75(2)°, V =3262(2) A 3 and Z =8 [ d calcd =1.660 g cm −3 ; μ a (Mo K α )=1.66 mm −1 ]. Solution 1 H, 13 C and 113 Cd NMR studies of complex 3 suggest that in non-polar solvents, such as CDCl 3 , the seven-coordinate structure is maintained, while in aqueous media dissociation of one axial chloride ligand affords a macrocyclic ligand-folded six-coordinate species. This is analogous to the dichloromanganese(II) complex 1 . Folding of the pentaazamacrocyclic ligand 5 is confirmed as a relevant structural motif for this series of complexes by the X-ray structure determination of the bis(nitrate) derivative. Complex 4 [Cd(C 10 H 25 N 5 )NO 3 ]NO 3 reveals a six-coordinate structure with a folded conformation of the macrocyclic ligand. Crystal data for [Cd(C 10 H 25 N 5 )NO 3 ]NO 3 is as follows: orthorhombic at 20 °C, space group P2 1 2 1 2 1 −D 4 2 (No. 19) with a =9.627(2) A, b =12.858(2) A, c =14.003(2) A, V =1733.3(6) A 3 and Z =4 [ d calcd =1.731 g cm −3 ; μ a (Mo K α )=1.30 mm −1 ]. Solution 1 H, 13 C and 113 Cd NMR studies of complex 4 suggest six-coordinate structures in both CDCl 3 and D 2 O, again with the macrocyclic ligand in a folded conformation. Again, this is entirely analogous to the Mn(II) bis(nitrate) complex 2 . 113 Cd NMR shifts are consistent with literature predictions for the types and numbers of coordinating ligands in complexes 3 and 4 in both NMR solvents. Figure options Download full-size image Download as PowerPoint slide

Synthesis and SOD activity of manganese complexes of substituted pyridino pentaaza macrocycles that contain axial auxiliary

New manganese(II) complexes of substituted pyridino pentaaza macrocyclic ligands were prepared. The amino-, carboxy-, or other functional groups were placed in the vicinity of the axial position of the metal complex. Their SOD-like activity was determined by cytochrome c assay and compared with one another. The activities of pyridine analogs ( 12a– b and 13) and m-substituted analogs ( 12c and 12j) were similar and significantly better than that of the standard compound M-40403. The most potent compound was an o-aminobenzoyl derivative 12i, while the o-carboxybenzoyl analog 12d was the lowest active compound.

Synthesis and characterization of some new Pb(II), Mn(II) and Ag(I) complexes with a pentaaza macrocyclic ligand containing a piperazine moiety

A pentaaza (N 5) 17-membered macrocyclic ligand (L) has been synthesized and its coordination capability toward perchlorate or nitrate salts of Mn(II), Pb(II) and Ag(I) has been investigated. The complexes were characterized by elemental analysis, IR, FAB mass spectrometry, magnetic studies, conductivity measurements, 1H and 13C NMR spectroscopy. The crystal structure of [PbL](ClO 4) 2 has been determined and it shows the presence of a mononuclear complex, with the Pb(II) ion coordinated to the five N donor atoms of the ligand in a hemidirected structure with the presence of a stereochemically active lone pair of electrons on the Pb(II) ion.

Late first-row transition-metal complexes of texaphyrin.

The preparation of first-row transition-metal complexes of texaphyrin, a porphyrin-like, monoanionic penta-aza macrocyclic ligand, is reported. Specifically, the synthesis of organic-soluble Mn(II) (1), Co(II) (2), Ni(II) (3), Zn(II) (4), and Fe(III) (5) texaphyrin derivatives and their water-soluble counterparts (6-10) from appropriate metal-free, nonaromatic macrocyclic precursors is described. It was found that metal cations of sufficient reduction potential could act to oxidize the nonaromatic macrocyclic precursor in the course of metal insertion. Complexes were characterized by X-ray diffraction analysis, electrochemistry, flash photolysis, and EPR spectroscopy. The structural and electronic properties of these "expanded porphyrin" complexes are compared with those of analogous porphyrins. Notably, the texaphyrin ligand is found to support the complexation of cations in a lower valence and a higher spin state than do porphyrins. Interactions between the coordinated cation and the ligand pi system appear to contribute to the overall bonding. Texaphyrin complexes of Mn(II), Co(II), and Fe(III) in particular may possess sufficient aqueous stability to permit their use in pharmaceutical applications.

Synthesis, characterization and solution 113Cd NMR analysis of Cd(II) 1,4,7,10,13-pentaazacyclopentadecane complexes

Two new cadmium(II) complexes of the macrocyclic ligand, 1,4,7,10,13-pentaazacyclopentadecane 5, have been prepared and characterized. The crystal structure of dichlorocadmium(II) complex 3 was determined and reveals that the Cd(II) is coordinated in a pentagonal bipyramidal array of the five nitrogens of the macrocyclic ring and capped by two trans-chloro ligands. Crystal data for Cd(C 10H 25N 5)Cl 2–0.5H 2O are as follows: monoclinic at 20 °C, space group C2/c−C 6 2h (No. 15) with a =22.165(5) Å, b =11.439(3) Å, c =14.6788(4) Å, β=118.75(2)°, V=3262(2) Å 3 and Z=8 [ d calcd=1.660 g cm −3; μ a(Mo K α)=1.66 mm −1]. Solution 1H, 13C and 113Cd NMR studies of complex 3 suggest that in non-polar solvents, such as CDCl 3, the seven-coordinate structure is maintained, while in aqueous media dissociation of one axial chloride ligand affords a macrocyclic ligand-folded six-coordinate species. This is analogous to the dichloromanganese(II) complex 1. Folding of the pentaazamacrocyclic ligand 5 is confirmed as a relevant structural motif for this series of complexes by the X-ray structure determination of the bis(nitrate) derivative. Complex 4 [Cd(C 10H 25N 5)NO 3]NO 3 reveals a six-coordinate structure with a folded conformation of the macrocyclic ligand. Crystal data for [Cd(C 10H 25N 5)NO 3]NO 3 is as follows: orthorhombic at 20 °C, space group P2 12 12 1−D 4 2 (No. 19) with a =9.627(2) Å, b =12.858(2) Å, c =14.003(2) Å, V=1733.3(6) Å 3 and Z=4 [ d calcd=1.731 g cm −3; μ a(Mo K α)=1.30 mm −1]. Solution 1H, 13C and 113Cd NMR studies of complex 4 suggest six-coordinate structures in both CDCl 3 and D 2O, again with the macrocyclic ligand in a folded conformation. Again, this is entirely analogous to the Mn(II) bis(nitrate) complex 2. 113Cd NMR shifts are consistent with literature predictions for the types and numbers of coordinating ligands in complexes 3 and 4 in both NMR solvents.

Iron(III) Complexes as Superoxide Dismutase Mimics: Synthesis, Characterization, Crystal Structure, and Superoxide Dismutase (SOD) Activity of Iron(III) Complexes Containing Pentaaza Macrocyclic Ligands

Iron(III) complexes with four pentaaza macrocylic ligands, [Fe(L)Cl2](PF6), have been synthesized, where the ligand L is 1,4,7,10,13-pentaazacyclopentadecane (L1), 2R,3R,8S,9S-dicyclohexano-1,4,7,10,13-pentaazacyclopentadecane (L2), 2R,3R,8R,9R -dicyclohexano-1,4,7,10,13-pentaazacyclopentadecane (L3), or 2S,5R,8S,11R,14S-pentamethyl-1,4,7,10,13-pentaazacyclopentadecane (L4), respectively. Conductivity measurements in acetonitrile are consistent with two chloro anions coordinated to iron(III). In acetonitrile solution, all four iron complexes exhibit a reversible or quasi-reversible redox couple in the experimental range −1.5 to +1.5 V vs EAg/Ag+, and the redox potentials for those four complexes are similar (from −0.15 to −0.19 V vs NHE). In aqueous solutions, the electrochemical properties of those complexes are different from those in acetonitrile solution; the redox peaks shift more than 0.5 V more positive. The complexes with L1, L2, and L3 display a reversible redox at 0.35, 0.45, and 0.43 V vs NHE, ...

NINETEEN-MEMBERED PENTAAZAMACROCYCLIC COMPLEXES BEARING TETRAAMIDE GROUPS

A new series of CoII, NiII, CuII and ZnII complexes incorporating pentaazamacrocyclic ligands has been prepared via the template condensation of o-aminobenzoic acid with succinic or phthalic acids in the presence of diethylenetriamine. The overall geometry and mode of bonding have been deduced on the basis of elemental analyses, i.r., 1H-n.m.r., e.p.r. and u.v.-vis. spectral studies, and conductivity and magnetic susceptibility measurements. An octahedral geometry is proposed for all the complexes, where five coordination sites are occupied by the macrocyclic nitrogens and the sixth by an anion.

ChemInform Abstract: Nickel(II), Copper(II), and Zinc(II) Complexes of Pentaazamacrocyclic Ligands. Crystal and Molecular Structure of 3,6,9,12‐Tetramethyl‐3,6,9,12,18‐pentaazabicyclo(12.3.1)octadeca‐1(18),14,16‐trienezinc(II) Perchlorate.

AbstractThe three related pentaazamacrocyclic ligands (VII) are prepared as shown.

Studies of pendant arm macrocyclic ligands. Part 6. Synthesis of two penta-aza macrocyclic ligands containing single pendant co-ordinating 2-pyridylmethyl and 1-pyrazolylmethyl arms, and characterisation of their nickel(II), copper(II), cobalt(II), and zinc(II) complexes. Crystal structure of {3,11-dibenzyl-7-(2′-pyridylmethyl)-3,7,11,17-tetra-azabicyclo[11.3.1]-heptadeca-1(17),13,15-triene}zinc(II) perchlorate

Reaction of the secondary amine group of 3,11-dibenzyl-3,7,11,17-tetrazabicyclo[11.3.1]heptadeca-1(17),13,15-triene (L2) with 2-chloromethylpyridine in the presence of base, or with 1-(hydroxymethyl)pyrazole, gives two new pendant-arm macrocycles, L3 and L4, having 7-(2′-pyridylmethyl) and 7-(1′-pyrazolylmethyl) groups, respectively. Complexes of Co2+, Ni2+, Cu2+, and Zn2+ with L3 and L4 have been isolated and characterised. The structure of [Zn(L3)][ClO4]2 has been established by X-ray crystallography, and confirms solution 1H n.m.r. studies; the two benzyl groups and the pendant arm lie on the same side of the macrocycle. Protondecoupled 13C n.m.r. spectra of the Zn2+ complexes of L3 and L4 show the presence of only a single symmetric isomer in each case. In the [Zn(L4)(dmso)]2+ ion, the presence of a strongly co-ordinated dimethyl sulphoxide (dmso) molecule is confirmed both in the solid state and in solution, and solid complexes of formula [M(L)(dmso)][ClO4]2(L = L3 or L4; M = Co, Ni, or Cu) have been prepared in all cases.

ChemInform Abstract: Pendant‐Arm Macrocyclic Ligands. Part 5. Synthesis of Two Pyridine‐Containing Penta‐aza Macrocycles with Single Pyrrolidinyl Pendant Arms and Characterisation of Their Nickel(II) and Copper(II) Complexes. Crystal Structure of Perchlorato(7‐(2′‐(1′′‐pyrrolidinyl)ethyl)‐3,7,11,17‐tetraazabicyclo(11.3.1)heptadeca‐1(17),13,15‐triene)nickel(II) Perchlorate.

AbstractThe two pentaaza macrocyclic ligands (VI) containing an exocyclic pyrrolidinylalkyl group are prepared as shown in the scheme.

Cobalt(II) and Cobalt(III) Complexes of Pentaaza Macrocyclic Ligands. Isomeric Composition and Hydrolysis Reactions of the Complexes of Eight Ligands With 15-Membered to 20-Membered Macrocyclic Rings

Synthesis and characterization of cobalt(III) complexes of the pentaaza macrocyclic ligands 1,4,7,10, 13-pentaazacyclopentadecane, ( cpad ), 1,4,7,10,13-pentaazacyclohexadecane, ( ched ), 1,4,7,10,14-pentaazacycloheptadecane, ( chad ), 1,4,7,11,14-pentaazacycloheptadecane, ( chbd ), 1,4,7,11, 15-pentaazacyclooctadecane, ( coad ), 1,4,8,11,15-pentaazacyclooctadecane, ( cobd ) are described. Of the different isomeric forms possible for each complex only one geometric isomer and one or two of the possible diastereoisomers have been isolated. The products of the induced acid hydrolysis reactions of the bromo and chloro complexes with these ligands have been identified by means of 13C n.m.r. spectroscopy. Nitrato complexes are commonly produced when the reaction proceeds in nitrate media. The reactions of the [Co( cpad )X]n+ and [Co( chbd )X]n+ complexes proceed with the apparent inversion of a coordinated nitrogen in strongly acid media. Cobalt(II) complexes of the ligands 1,4,8,12,16-pentaazacyclononadecane ( cnad ) and 1,5,9,13,17-pentaazacycloeicosane (ceic) were prepared. These complexes could not be oxidized to cobalt(III) complexes and the available evidence suggests that they are five-coordinate square-pyramidal complexes in the solid state and in solution.

Studies of pendant-arm macrocyclic ligands. Part 5. Synthesis of two pyridine-containing penta-aza macrocycles with single pyrrolidinyl pendant arms and characterisation of their nickel(II) and copper(II) complexes. Crystal structure of perchlorato{7-[2′-(1″-pyrrolidinyl)ethyl]-3,7,11,17-tetra-azabicyclo[11.3.1]heptadeca-1(17),13,15-triene}nickel(II) perchlorate

Two new pyridine-containing penta-aza macrocyclic ligands, 7-[2′-(1″-pyrrolidinyl)ethyl]- and 7-[3′-(1″-pyrrolidinyl)propyl]-3,7,11,17-tetra-azabicyclo[11.3.1]heptadeca-1 (17),13,15-triene (L1 and L2 respectively) have been prepared, and their nickel(II) and copper(II) complexes of formulae [M(L1)(OClO3)][ClO4] and [M(HL)][ClO4]3(M = Ni or Cu, L = L1 or L2) have been isolated and characterised. In the octahedral complex [Ni(L1)(OClO3)][ClO4] the presence of a co-ordinated perchlorate group has been established by X-ray crystallography, and the macrocyclic ligand found to co-ordinate close to the corners of a square pyramid with the pendant pyrrolidinyl group at the apical position.

Nickel(II), copper(II), and zinc(II) complexes of penta-azamacrocyclic ligands. Crystal and molecular structure of 3,6,9,12-tetramethyl-3,6,9,12,18-penta-azabicyclo[12.3.1]octadeca-1(18),14,16-trienezinc(II) perchlorate

The three related penta-azamacrocyclic ligands 6,9-dimethyl-2,13-dioxo-3,6,9,12,18-penta-azabicyclo[12.3.1]octadeca-1(18),14,16-triene (L1), 6,9-dimethyl-3,6,9,12,18-penta-azabicyclo[12.3.1]octadeca-1 (18),14,16-triene (L2), and 3,6,9,12-tetramethyl-3,6,9,12,18-penta-azabicyclo[12.3.1]octadeca-1(18),14,16-triene (L3), have been prepared. The complexes [M(L)(dmso)][ClO4]2(dmso = dimethyl sulphoxide; L = L2, M = Ni or Zn; L = L3, M = Ni) and [M(L)][ClO4]2(L = L2, M = Cu; L = L3, M = Cu or Zn) have been isolated. The Ni2+ complexes are high-spin and six-co-ordinate, and the Cu2+ complexes five-co-ordinate. 13C N.m.r. spectroscopy shows [Zn(L2)(dmso)][ClO4]2 to be a 2 : 1 mixture of two species, one symmetric and the other asymmetric, whilst in [Zn(L3)][ClO4]2 only ca. 10% of the asymmetric species is present in nitromethane solution. X-Ray crystallography has been used to dermine the structure of the symmetric isomer of [Zn(L3)][ClO4]2{R= 0.039 for 1 816 observed [I/σ(I) 3.0] diffractometer collected reflections}; it reveals distorted trigonal-bipyramidal geometry about the zinc ion, and an approximate C2 rotation axis passing through the zinc and pyridine N atoms, and bisectinig the macrocyclic C–C bond furthest removed from the pyridine ring [Zn–N 1.999(4)–2.252(5)A].

Electrochemical and spectrophotometric studies of iron complexes with a pentaaza macrocyclic ligand

Aqueous solutions of complexes of iron(III) and iron(II) and the macrocyclic ligand 2,13-dimethyl-3,6,9,12,18-pentaazabicyclo(12.3.1)octadeca-1(18),2,12,14,16-pentaene (B) were investigated by voltammetry, chronocoulometry, and controlled-potential coulometry. Standard potentials for redox reactions involving species in this system, which include FeB/sup 3 +/, FeB(OH)/sup 2 +/, and FeB/sup 2 +/, as well as binuclear species such as (FeB)/sub 2/O/sup 4 +/, were obtained, and reactions involving decomposition of these at different pHs were investigated. Spectrophotometric measurements were also employed in the elucidation of the chemistry of this system. 17 references, 11 figures, 4 tables.

A new pyridyl-containing pentaaza macrocyclic ligand. Stabilization in aqueous solutions of the iron(II) complex and its dioxygen adduct

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTA new pyridyl-containing pentaaza macrocyclic ligand. Stabilization in aqueous solutions of the iron(II) complex and its dioxygen adductEiichi Kimura, Mutsuo Kodama, Ryosuke Machida, and Kazuhiko IshizuCite this: Inorg. Chem. 1982, 21, 2, 595–602Publication Date (Print):February 1, 1982Publication History Published online1 May 2002Published inissue 1 February 1982https://doi.org/10.1021/ic00132a026RIGHTS & PERMISSIONSArticle Views163Altmetric-Citations37LEARN 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 (986 KB) Get e-Alerts Get e-Alerts

Accessibility of manganese oxidation states. Control by pentaaza macrocyclic ligands

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAccessibility of manganese oxidation states. Control by pentaaza macrocyclic ligandsJames C. Dabrowiak, Laurence A. Nafie, Philip S. Bryan, and Andrew T. TorkelsonCite this: Inorg. Chem. 1977, 16, 3, 540–544Publication Date (Print):March 1, 1977Publication History Published online1 May 2002Published inissue 1 March 1977https://doi.org/10.1021/ic50169a007RIGHTS & PERMISSIONSArticle Views204Altmetric-Citations20LEARN 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 (682 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts