α1- andα2-Adrenoreceptor Antagonist Profiles of 1- and 2-[ω-(4-Arylpiperazin-1-yl)alkyl]-1,2,3-benzotriazoles

Boido, A.; Budriesi, Roberta; Boido, Caterina Canu; Ioan, Pierfranco; Terranova, E.; Chiarini, Alberto; Sparatore, Fabio

doi:10.1002/cbdv.200590100

Cited by 1 publication

(2 citation statements)

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“…18 In addition, 2 exhibits two weak absorption bands at 850 and 540 nm (respective e values are 41 and 1150 L mol -1 cm -1 ) owing to the d-d transitions of the octahedrally coordinated HS and LS Fe II ions, respectively. 17 The absorption peak at 540 nm is probably due to transition from 1 A 1g to 1 T 2g , whereas the weak, broad absorption peak at 850 nm is attributed to transitions from 5 T 2g to 5 The solid state UV-Vis spectrum (Fig. 4b) of 2 recorded at room temperature exhibits bands similar to those found in the solution UV-Vis spectrum.…”

Section: Uv-vis Spectroscopymentioning

confidence: 82%

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Thermal spin-crossover in the [M3Zn6Cl6L12] (M = Zn, FeII; L = 5,6-dimethoxy-1,2,3-benzotriazolate) system: structural, electrochemical, Mössbauer, and UV-Vis spectroscopic studies

et al. 2010

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Fusion of pentanuclear Kuratowski-type coordination units leads to homo- and heterononanuclear coordination compounds, two of which are presented, having structural formulae [Zn(9)Cl(6)(OMe(2)bta)(12)]·DMF (1), and [Fe(II)(3)Zn(6)Cl(6)(OMe(2)bta)(12)]·DMF (2), respectively; (OMe(2)btaH = 5,6-dimethoxy-1,2,3-benzotriazole; DMF = N,N'-dimethylformamide). Single crystal X-ray structure analyses reveal the presence of {M(3)Zn(6)L(12)}(6+) cores (M = Zn or Fe(II); L = 5,6-dimethoxy-1,2,3-benzotriazolate) in which the M(II) ions are bridged by μ(3)-OMe(2)bta ligands. In both compounds, the six peripheral Zn ions are tetracoordinated, whereas the remaining three metal ions M are hexacoordinated. The charge of each {M(3)Zn(6)L(12)}(6+) moiety is balanced by six chloride anions that are monodentately bound to the peripheral Zn ions. Based on differences in experimental Fe-N-donor bond lengths (deduced from single crystal data of 2 recorded at 223 K), two out of three Fe(II) ions are found in a high-spin (HS) state, whereas one Fe(II) ion shows a low-spin (LS) state. The assignment of different energetic ground states of Fe(II) ions is corroborated by spectroscopic studies: Both solid-state and solution UV-Vis spectra of 2 (at ambient temperature) display absorption bands owing to the presence of both HS and LS Fe(II) ions. Removal of occluded DMF molecules from the crystal lattices of 1 and 2 in high vacuum leads to fully desolvated powders, termed hereafter 1a and 2a, respectively. Mössbauer studies on 2a show that all three Fe(II) ions are in HS state at 160 K, and upon cooling to 7 K, the central Fe(II) ion undergoes a HS→LS transition while the HS states of the other Fe(II) ions remains unchanged. The cyclic voltammogram of 2 (chloroform solution) exhibits a single reversible oxidation regardless of different Fe(II) spin states in the nonanuclear core of 2.

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Section: Uv-vis Spectroscopymentioning

confidence: 82%

“…The OMe 2 btaH ligand was synthesized as described previously. 5 All other starting materials were of reagent grade and used as received from the commercial supplier. Fourier transform infrared (FTIR) spectra were recorded from KBr pellets in the range 4000-400 cm -1 on a Bruker IFS FT-IR spectrometer.…”

Section: Experimental Materials and General Methodsmentioning

confidence: 99%