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The supramolecular interactions of 2,9-di(((2'-phenylamino) ethyleneamino)methyl)-l,10-phenanthroline (L) and (or) metal ions (M = [Ca.sup.2+], [Mg.sup.2+], [Zn.sup.2+], or [La.sup.3+]) with nucleotides were investigated. Furthermore, the hydrolysis of ATP catalyzed by a protonated ligand and (or) a metal ion (M = [Ca.sup.2+], [Mg.sup.2+], [Zn.sup.2+], or [La.sup.3+]) was studied at pH 7.6 using [sup.31]P NMR spectra. Kinetics studies show that at pH 7.6 the protonated ligand, with a rate constant of 2.9 x [10.sup.-4] [min.sup.-1], does not significantly promote ATP hydrolysis. However, in the presence of [Ca.sup.2+], [Mg.sup.2+], [Zn.sup.2+], or [La.sup.3+] ions, L can accelerate the hydrolysis of ATP, with corresponding rate constants of 5.73, 1.48, 6.76, and 31.7 x [10.sup.-3] [min.sup.-1], respectively, which are about 29-, 7.5-, 34-, and 159-fold faster than the hydrolysis rate of free ATP. By comparison with M-ATP (M = [Ca.sup.2+], [Mg.sup.2+], and [La.sup.3+]) systems, the rates of M-L-ATP were also promoted. This has been achieved through the effective recognition of ATP and the availability of a good intramolecular nucleophile, i.e., a free amino nitrogen atom of L. Compared with the [Zn.sup.2+]-ATP system, the decrease in the rate of the [Zn.sup.2+]-L-ATP system at pH 7.6 may be attributed to the competition between the mixed ligands in binding [Zn.sup.2+]. Similar to L-ATP, the hydrolysis reactions in the [Zn.sup.2+]-L-ATP or M-L-ATP (M = [Ca.sup.2+], [Mg.sup.2+], and [La.sup.3+]) systems occur through an addition--elimination type mechanism, in which phosphoramidate intermediates were observed at 2.88 and 4.06 parts per million (ppm) in the L-ATP and [Mg.sup.2+]-L-ATP systems, respectively. Here, metal ions add control or regulation to the hydrolysis reaction. Key words: recognition, ATP hydrolysis, metal ions, phenanthroline-bridged polyamine.

Potentiometric determination shows that trinuclear Zn(II) complexes of the four tripods 1,3,5-tri(2',5'-diazahexyl)benzene (L1), 1,3,5-tri(2',5'-diazaheptyl)benzene (L2), 1,3,5-tri(2',5'-diazaoctyl)benzene (L3), and 1,3,5-tri(2', 5'-diazanonyl)benzene (L4) could be potential hydrolytic catalysts. C[H.sub.3]CN solutions containing [[3Zn:L].sup.T] (0.5~2 x [10.sup.-3] mol x [dm.sup.3]) with I = 0.10 mol x [dm.sup.-3] of KN[O.sub.3] and Good's buffer (10% volume fraction) were studied for the catalyzing hydrolysis of p-nitrophenyl acetate (NA, 0.5~2 x [10.sup.-3] mol x [dm.sup.-3]), at 298 K, in the 6.5-8.2 pH range. The observed rate constants, [k.sub.obs], fit the equilibrium equation [k.sub.obs] = [k.sub.com] [[3Zn:L].sup.T] + [k.sub.OH][O[H.sup.-]] + [k.sub.0]. The sigmoid pH~[k.sub.com] profiles for NA hydrolysis suggest that either the Zn(II)-bound hydroxyl or the Zn(II)-bound water forms of the catalysts can be the active species. The observed second-order rate constants are 0.0082, 0.011, 0.0059, and 0.0019 [mol.sup.-1] x [dm.sup.3] x [s.sup.-1] for the four [Zn.sub.3]L-[H.sub.2]O complexes ([k.sub.A]) and 0.342, 0.257, 0.382, and 0.091 [mol.sup.-1] x [dm.sup.3] x [s.sup.-1] for the four [Zn.sub.3]L-O[H.sup.-] groups ([k.sub.B]), respectively. However, under the condition that [NA] = 0.5 x [10.sup.-3] mol x [dm.sup.-3] and [[3Zn:L1].sup.T] = 2~4 x [10.sup.-2] mol x [dm.sup.-3] at pH 7.6, the observed rate constants, [k.sub.obs], obey the equilibrium [k.sub.obs] = [k.sub.com][[3Zn:L].sup.T]/(1/K' + [[3Zn:L].sup.T]). This indicates that the 3:1 complex (or its deprotonated hydroxide form) mediates NA hydrolysis by nucleophilic attack of the carboxyl center with the pre-formation of a coordination bond between the carboxyl oxygen atom and the Zn(II) ion. Comparison with other models was made, and the reasons for the high catalytic efficiency of the tripodal complexes were given. Key words: tripod, Zn(II), catalysis, NA hydrolysis, polynuclear.

Two novel linear polyamine ligands, N,N'-bis-(2-(N"-2-hydroxyl-5-bromobenzyl)aminoethyl) malondiamide ([L.sub.1] and N,N'-bis-(3-(N"-2-hydroxyl-5-bromobenzyl)aminopropyl) malondiamide ([L.sub.2]), have been synthesized and fully characterized by elemental analysis (sup.1]H NMR and IR spectroscopy) (Fig. 1). The binding ability of ligands [L.sub.1] and [L.sub.2] to metal ions such as Cu(II), Zn(II), Co(II), Mu(II), Mg(II), and Ca(II) has been investigated by the potentiometric method in 1,4-dioxane-water (v/v = 15:100) and KN[O.sub.3] (0.1 mol [dm.sup.-3]) at 25.0[degrees]C. In view of the linear structures of [L.sub.1] and [L.sub.2], binuclear metal complexes can be formed in solution by controlling Cu(II)-5-substituted o-pbenanthroline (Rpben, R = C[H.sub.3], H, Cl, N[O.sub.2]):L to a 2:1 molar ratio, whereas the mononuclear metal complexes form at molar ratio M(II):L of 1:1, where M(II) is Cu(II), Zn(II), Co(II), Mn(II), Mg(II), and Ca(II). The stability constants of metal complexes have been determined and further discussed. In addition, two manganic complexes have been synthesized and IR and electronic spectra showed their coordination nature. Key words: linear polyamine ligand, 5-substituted o-phenanthroline, mononuclear and binuclear metal complex, stability, spectrum.

A new route to obtain C-functionalized dioxotetraamine, in which two independent chelating groups 8-quinolinol and dioxotetraamine are included, is described. In addition, two trinuclear metal complexes are synthesized and fully characterized. The thermodynamic properties of the ligand and its respective metal complex were investigated by a potentiometric titration method. Coupled with UV spectra, the difference in affinities for copper ion between dioxotetraamine and 8-quinolinol in the new ligand are investigated and the results show that 8-quinolinol is a stronger donor group than the dioxotetraamine macrocycle in an aqueous solution. Over pH 3~11, 8-quinolinol interacts 100% with the copper ions while dioxotetraamine is only partially coordinated. Key words: macrocycle, dioxotetraamine, 8-quinolinol, copper ion, stability constants.