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Three atropisomeric tetrasaccharide-substituted zinc porphyrins(αβαβ-Zn-A,ααββ-Zn-A,and αααβ-Zn-A) and one monosaccharide-substituted zinc porphyrin(Zn-B) were synthesized.We explored the interactions of these zinc porphyrins with a set of amino acid methyl esters(L/D-LeuOMe,L/ D-ThrOMe,L/D-ValOMe,and L/D-PheOMe)using visible titration and circular dichroism(CD) spectroscopy.We observed that all of them bind to L-amino acid methyl esters more closely than to those with D-configuration.In particular,ααββ-Zn-A gives a high enantioselectivity,K_L /K_D,of 4.75,and could be used for chiral recognition of amino acid methyl esters.The binding constants of the three Zn-A compounds with methyl amino acid methyl esters are in the same order,i.e.,K~(LeuOMe)K~(ValOMe)K~(ThrOMe) K~(PheOMe),but the order of the binding constants for Zn-B is K~(PheOMe)K~(LeuOMe)K~(ValOMe)K~(ThrOMe).In addition,we used imidazole as a probe to study the effects of achiral molecules on the conformations of the glycoconjugated porphyrins.The experimental results show that binding with imidazole causes adjustments in the conformations of the Zn-A compounds.The binding constants of the Zn-A compounds with imidazole and with methyl amino acid methyl esters are in the same order: K~(ααββ-Zn-A)K~(αβαβ-Zn-A)K~(αααβ-Zn-A).

We synthesized two terminal alkynyl modified Salen ligands, H2L, and their metal complexes, ML (n=1, 2, M=Ni, Cu, Mn). The ligands and complexes were characterized by H nuclear magnetic resonance (H NMR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS), elemental analysis, Fourier transform infrared (FT-IR) spectroscopy, and ultraviolet visible (UV-Vis) spectroscopy. The redox properties of the compounds were investigated with cyclic voltammetry (CV). Imine redox peaks appeared in the CV curves of all the ligands except H2L. The Ni and Cu complexes underwent two single electron redox processes in the scanning range. Mn complexes gave a pair of quasi-reversible voltammetric peaks, which corresponded to the redox process between Mn(III)/Mn(II). Molar conductivity measurements of the complexes showed that they were all weak electrolytes with certain conductivity.

The novel μ-oxo diiron(III) Schiff base complexes, {[Fe(tbusalphn)]2(μ-O)} (1) [tbusalphn = N,N′-o-pheny-lenebis(3,5-di-tert-butylsalicylideneiminato)] and {[Fe(R,R-salchxn)]2(μ-O)}(2) [R,R-salchxn = N,N′-R,R-cyclo-hexanebis(salicylideneiminato)] have been synthesized and characterized by elemental analyses, spectroscopy, magnetic susceptibility, electrochemical measurements and X-ray diffraction techniques. X-ray analyses revealed that the complex 1·CH3OH has nearly linear Fe-O-Fe angle of 176.5(2)° due to their steric crowding of ligands owing bulky substitute group, while fairly bent Fe-O-Fe angle was allowed by the reduced steric crowding of the ligands in 2·C4H6N2·0.5C2H5OH [149.6(1)°]. FT-IR, UV-Vis, CD spectra, magnetic susceptibility and cyclic voltammogram (CV) of complexes 1 and 2 have been further investigated.