A. Moghimi et al. / Journal of Molecular Structure 996 (2011) 38–41
41
Pd–N3, Pd–N5 and Pd–O1 are different, as expected, as a result of
the asymmetric coordination imposed by mixed asymmetric
ligands. These four bonds are 2.082(2), 1.967(2), 1.982(2) and
2.010(2) Å, respectively which are within the reported range of
Pd–O and Pd–N bonds in PdII tetracoordinated complexes [17].
Chelated angles N3–Pd–N5, N5–Pd–N1, N5–Pd–O1, N3–Pd–O1 and
N3–Pd–N1 are 86.88(10)°, 102.62(10)°, 175.09(10)°, 88.31(10)°
and 170.42(9)°, respectively, confirming the absence of planarity.
It is noted that in the case of previously reported (pip-
zH2)[Pd(dipic)2].2H2O, coordination sphere around PdII is square
planar, N–Pd–N and O–Pd–O angles being 179.83(5)° and
179.68(6)°, respectively.
Center, 12 Union Road, Cambridge, CB2, 1EZ, UK (fax: +44
(0)1223 336033 or email: deposit@ccdc.cam.ac.uk).
Acknowledgement
Financial support by Imam Hossein University is gratefully
acknowledged.
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Dipic and Met play as chelating ligands in the PdII metal
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compound with PdCl2, suitable crystals for X-ray are prepared.
From the chemical structure of the resulting complex it may be
concluded that other mix metal complexes involving metformin
and dipicolinic acid could be prepared following the same strategy.
Considering the previously reported biological activities of Cobalt
and Vanadium complexes of pyridinedicarboxylic acids, and
oxovanadium metformin complexes, the vanadium complex of
(MetH)2(dipic) possibly could benefit the presence of dipic, Vana-
dium and Met simultaneously in a single compound. This could im-
prove the potential and possible synergy of vanadium complexes.
It seems to us that there is a significant potential for further
development of these complexes as insulin-mimic compounds.
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P
2
1=2
[13] Least squares function minimized; ½wðF2o ꢁ Fc2Þ = ðNo ꢁ N Þꢄ
.
v
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5. Supplementary data
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Full crystallographic data for the structural analysis have been
deposited with the Cambridge Crystallographic Data Center, CCDC
No. 734414. These data can be obtained free of charge via