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The resonance Raman spectra of water-soluble porphyrins, M(TMpy-P4) (M = Cu(II), Ni(II) and Co(III] and their mixtures with poly(dG-dC)2, poly(dA-dT)2 and calf thymus and salmon DNAs were measured using a divided rotating cell to determine the magnitudes of frequency shift and intensity variation resulting from M(TMpy-P4)-nucleic acid interactions. Bands II(C beta-H bending, approximately 1100 cm-1) and VIII(C beta-C beta stretch, approximately 1570 cm-1) show a large and small upward shift, respectively, when Cu(TMpy-P4) and Ni(TMpy-P4) are intercalated at the G-C sites. In contrast, these bands show a small upward and downward shift, respectively, when Co(TMpy-P4) is groove-bound at the A-T sites of nucleic acids. Both Bands V (approximately 1260 cm-1) and IX (approximately 1646 cm-1) which originate in the N-methylpyridyl group always show small downward shifts due to coulombic interaction between the N-CH3+ group of TMpy-P4 and the PO2 group of the nucleic acid.

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Calix [n]arenes are a class of macrocycles that have attracted much interest because of their potential for forming host-guest complexes, and have been extensively investigated in various fields. In this study, in an attempt to develop calix[n]arenes as an effective analytical reagent with enzyme-like activity, the peroxidase-like activity of the ion-exchangers modified with some metal complexes of thiacalix[4]arenetetrasulfonate (Fig. 1) was investigated. The modified ion-exchanger with the highest activity was applied for the determination of hydrogen peroxide and glucose in place of peroxidase.

The resonance Raman spectra of dioxygen adducts of anthracene pillared cofacial dicobalt(II) diporphyrin (Co-Co complex) have been measured in methylene chloride at ~190 K (457.9-nm excitation). In the absence of a base, the Co-Co complex forms a superoxo adduct in which dioxygen is bridged between the two porphyrin planes intramolecularly. This adduct exhibits the

Calix [n]arenes are of much interest because of their high selectivity and specificity for forming host-guest complexes. 2,3 In analytical chemistry, various calix[n]arene derivatives have been developed by modifying either the upper or lower rim in order to apply them as analytical reagents for separations 4-7 and sensors 8-12 of various ions, molecules, and so on. It has been shown that recently developed thiacalix[n]arenes have a very interesting characteristic: an ability to form very stable metal complexes without modifying the upper and/or lower rims. 13