Syntheses and aggregation properties of new squalene receptors bearing open chain ligands

Photoredox reactions occurring in irradiated methanolic solutions of trans-[FeIII(R,R'-salen)(CH3OH)I], where R,R'-salen2- are N,N'-ethylenebis(R,R'-salicylideneiminato), tetradentate open-chain N2O2-Schiff bases with R,R' = H, 5-Cl, 5-Br, 3,5-di-Br, 3,5-di-(CH3), 3-OCH3, 5-OCH3, have been investigated and their mechanism proposed. The complexes are redox-stable in the dark. Ultraviolet and/or visible irradiation of methanolic solution of the complexes induces photoreduction of Fe(III) to Fe(II). Depending on the composition of the irradiated solutions, •CH2OH radicals or solvated electrons were identified by the EPR spin trapping technique. The final product of the photooxidation coupled with the photoreduction of Fe(III) is formaldehyde and the molar ratio of Fe(II) and CH2O is close to 2 : 1. The efficiency of the photoredox process is strongly wavelength-dependent and influenced by the peripheral groups R,R' of the tetradentate ligands.

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Additions and Corrections - Photoelectron Spectra of Open Chain C6H6Isomers

Journal of the American Chemical Society ◽

10.1021/ja00424a604 ◽

1976 ◽

Vol 98 (8) ◽

pp. 2371-2371

Author(s):

Peter Bischof ◽

Rolf Gleiter ◽

Hennig Hopf ◽

Frank Lenich

Keyword(s):

Photoelectron Spectra ◽

Open Chain

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Aiding Factors in the Formation of Azaplatinacyclobutane Rings – X-ray and Crystal Structure of [Pt{CH(Ph)CH2NEt2-κC,κN}(N,N,N′,N′-tetramethylethylenediamine)]+ and of Its Open-Chain Precursor

European Journal of Inorganic Chemistry ◽

10.1002/ejic.200601219 ◽

2007 ◽

Vol 2007 (15) ◽

pp. 2144-2150 ◽

Cited By ~ 15

Author(s):

Giuseppe Lorusso ◽

Carmen R. Barone ◽

Nicola G. Di Masi ◽

Concetta Pacifico ◽

Luciana Maresca ◽

...

Keyword(s):

Crystal Structure ◽

Open Chain ◽

X Ray

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Synthesis of sandwich type acyclic tetra-nuclear silver(I)-N-heterocyclic carbene complexes for wound healing applications

Zeitschrift für Naturforschung C ◽

10.1515/znc-2020-0069 ◽

2020 ◽

Vol 75 (9-10) ◽

pp. 369-376

Author(s):

Ayesha Riaz ◽

Muhammad Adnan Iqbal ◽

Haq Nawaz Bhatti ◽

Muhammad Shahid

Keyword(s):

Alkyl Halides ◽

Wound Contraction ◽

Spectroscopic Techniques ◽

Open Chain ◽

Standard Drug ◽

Sandwich Type ◽

Benzimidazolium Salts ◽

Multistep Reaction

AbstractTwo meta-xylyl linked tetrakis-benzimidazolium salts (L1-L2) as multidentate ligands and two respective silver complexes (C1 and C2) were synthesized. A multistep reaction was done at room temperature, starting with simple benzimidazole and alkyl halides, going through precursors and salt formation by reflux and finally in situ deprotonation of tetrabenzimidazolium salts with Ag2O to yield respective tetra-nuclear Ag(I)-N-heterocyclic Carbene (NHC) complexes. Propyl and butyl groups were bonded at the terminal positions of tetra-azolium open chain salts. Characterization of compounds was done by analytical and spectroscopic techniques. On the basis of spectroscopic data, a chemical structure with open chains having four Ag(I) ions sandwiched between NHC layers was established. Potential of synthesized complexes (C1 & C2) for wound contraction was evaluated and compared with standard wound contraction gel. Percentage wound contraction of both complexes was found very close to that of standard drug used in parallel.

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ChemInform Abstract: A SIMPLE CARBON-13 NUCLEAR MAGNETIC RESONANCE SPECTROSCOPIC METHOD FOR DISTINGUISHING BETWEEN OPEN-CHAIN AND PSEUDOACID CHLORIDES

Chemischer Informationsdienst ◽

10.1002/chin.197846057 ◽

1978 ◽

Vol 9 (46) ◽

Author(s):

W. J. ELLIOTT ◽

J. FRIED

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Spectroscopic Method ◽

Open Chain ◽

Nuclear Magnetic

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A novel class of translationally invariant spin chains with long-range interactions

Journal of High Energy Physics ◽

10.1007/jhep08(2020)099 ◽

2020 ◽

Vol 2020 (8) ◽

Author(s):

B. Basu-Mallick ◽

F. Finkel ◽

A. González-López

Keyword(s):

Long Range ◽

Degrees Of Freedom ◽

Spin Chains ◽

Open Chain ◽

New Class ◽

Spin Interactions ◽

Long Range Interactions ◽

Spin Reversal ◽

Twisted Yangian ◽

Internal Degrees Of Freedom

Abstract We introduce a new class of open, translationally invariant spin chains with long-range interactions depending on both spin permutation and (polarized) spin reversal operators, which includes the Haldane-Shastry chain as a particular degenerate case. The new class is characterized by the fact that the Hamiltonian is invariant under “twisted” translations, combining an ordinary translation with a spin flip at one end of the chain. It includes a remarkable model with elliptic spin-spin interactions, smoothly interpolating between the XXX Heisenberg model with anti-periodic boundary conditions and a new open chain with sites uniformly spaced on a half-circle and interactions inversely proportional to the square of the distance between the spins. We are able to compute in closed form the partition function of the latter chain, thereby obtaining a complete description of its spectrum in terms of a pair of independent su(1|1) and su(m/2) motifs when the number m of internal degrees of freedom is even. This implies that the even m model is invariant under the direct sum of the Yangians Y (gl(1|1)) and Y (gl(0|m/2)). We also analyze several statistical properties of the new chain’s spectrum. In particular, we show that it is highly degenerate, which strongly suggests the existence of an underlying (twisted) Yangian symmetry also for odd m.

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