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The mixed-ligand [Ge(HMal) 2 (bipy)]·bipy·2H 2 O ( 1 ) and mixed-ligand-heterometallic [Ni(phen) 3 ][Ge(OH)(HMal) 2 ] 2 ·12H 2 O ( 2 ), [Ni(bipy) 3 ][Ge(OH)(HMal) 2 ] 2 ·12H 2 O ( 3 ) germanium complexes with malic acid (H3Mal) and heterocyclic amines 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) were obtained for the first time. It was established that in the IR-spectra of 1-3 stretching vibrations of aromatic rings n(C-CАr) ~ 1598-1493 cm -1 , ν(C-N) ~ 1315 cm -1 , ν(C-N) ~ 1315сm -1 , and also n(Ge-N) = 655 сm -1 (for 1 ), n(Ni-N) = 420 сm -1 (for 2 , 3 ) are presented. This evidences about the presence of bipy or phen in the molecules of compounds. The absorption bands n(C=O) ~ 1708 сm -1 , ν as (СOО-) ~ 1671 сm -1 , ν s (СOО-) ~ 1448 сm -1 are specific for the vacant carboxylic and monodentate protonated carboxylate groups (Dn = ν as (СOО-) – ν s (СOО-) ~ 220 сm -1 ). The absorption bands ν(C-O) ~ 1130 сm -1 of the alcoholic group ν(Ge-O) ~ 778-725 сm -1 have been also detected in the IR-spectra of 1-3 . The feature of heterometalic complexes 2, 3 is presence of deformation vibrations band of the bond Ge-O-Н ~ 855 сm -1 . In the mass-spectra of anions 2 and 3 the formation of same fragmentation ions [Ge(OH)(HMal)]·H 2 O and [Ge(HMal) 2 ] with m/z ~ 243 and 337. In the compounds 1-3 malic acid coordinates in the monoprotonated form, one hydroxyl and one carboxyl groups take part in the formation of bonds with Ge(IV) atom, the second carboxyl group stays vacant. In the complex 1 the octahedral coordination polyhedron of Ge is formed through the bidentate coordination of 2,2'-bipyridine (bipy). Complexes 2,3 are of cationanionic type with the electrostatic interaction between their cations and anions. In 2,3 Germanium has coordination number 5 and saturates its coordination sphere by binding to the OH-group, and as the result similar complex anion with the composition [Ge(OH)(HMal) 2 ] - is formed. Cations [Ni(bipy/рhen)3]2+ are formed through the coordination three molecules of 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) by nickel atom.The mixed-ligand [Ge(HMal) 2 (bipy)]·bipy·2H 2 O ( 1 ) and mixed-ligand-heterometallic [Ni(phen) 3 ][Ge(OH)(HMal) 2 ] 2 ·12H 2 O ( 2 ), [Ni(bipy) 3 ][Ge(OH)(HMal) 2 ] 2 ·12H 2 O ( 3 ) germanium complexes with malic acid (H3Mal) and heterocyclic amines 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) were obtained for the first time. It was established that in the IR-spectra of 1-3 stretching vibrations of aromatic rings n(C-CАr) ~ 1598-1493 cm -1 , ν(C-N) ~ 1315 cm -1 , ν(C-N) ~ 1315сm -1 , and also n(Ge-N) = 655 сm -1 (for 1 ), n(Ni-N) = 420 сm -1 (for 2 , 3 ) are presented. This evidences about the presence of bipy or phen in the molecules of compounds. The absorption bands n(C=O) ~ 1708 сm -1 , ν as (СOО-) ~ 1671 сm -1 , ν s (СOО-) ~ 1448 сm -1 are specific for the vacant carboxylic and monodentate protonated carboxylate groups (Dn = ν as (СOО-) – ν s (СOО-) ~ 220 сm -1 ). The absorption bands ν(C-O) ~ 1130 сm -1 of the alcoholic group ν(Ge-O) ~ 778-725 сm -1 have been also detected in the IR-spectra of 1-3 . The feature of heterometalic complexes 2, 3 is presence of deformation vibrations band of the bond Ge-O-Н ~ 855 сm -1 . In the mass-spectra of anions 2 and 3 the formation of same fragmentation ions [Ge(OH)(HMal)]·H 2 O and [Ge(HMal) 2 ] with m/z ~ 243 and 337. In the compounds 1-3 malic acid coordinates in the monoprotonated form, one hydroxyl and one carboxyl groups take part in the formation of bonds with Ge(IV) atom, the second carboxyl group stays vacant. In the complex 1 the octahedral coordination polyhedron of Ge is formed through the bidentate coordination of 2,2'-bipyridine (bipy). Complexes 2,3 are of cationanionic type with the electrostatic interaction between their cations and anions. In 2,3 Germanium has coordination number 5 and saturates its coordination sphere by binding to the OH-group, and as the result similar complex anion with the composition [Ge(OH)(HMal) 2 ] - is formed. Cations [Ni(bipy/рhen)3]2+ are formed through the coordination three molecules of 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen) by nickel atom.

This study describes supramolecular assemblies of Cu(II) and Ni(II) 2,2′-bipyridine cations with dimeric tartratogermanate anions, namely [CuCl(bipy)2]2[Ge2(OH)2(Tart)2]·4H2O (I) and [Ni(bipy)3]4[{Ge2(OH)2(Tart)2}3Cl2]·15H2O (II). The compounds were characterized by elemental analysis, mass-spectrometry, IR-spectroscopy and X-ray analysis. The chloride ion coordinates to the Cu atom in cation I and two chloride ions together with the [Ge2(OH)2(Tart)2]2− anion neutralize the charge of the cation in II. The coordination polyhedra of the Ge atoms are trigonal bipyramids in the structures of I and II. The coordination polyhedra of two symmetrically independent [CuCl(bipy)2]1+ cations are distorted trigonal bipyramids in the structure of I, whilst the coordination polyhedra of the Ni cations in II are octahedral.

The cation-anionic coordination compounds based on the copper(II) complexes with Phen and tartratogermanate anions, [Cu(Phen)3]2[Ge2(OH)(HTart)(µ-Tart)2] · 11H2O (I) and [CuCl(Phen)2]4[{Ge2(OH)2(µ-Tart)2}Cl2] · 4Н2О (II), with different compositions and structures (CIF files CCDC nos. 1878102 (І) and 1878103 (ІІ)) are isolated for the first time from the GeO2–tartaric acid (H4Tart)–CuCl2–1,10-phenanthroline (Phen) system. The structures of compounds I and II contain the same bridging tartrate anions. A specific feature of compound I is the additional HTart3– anion, which does not perform the bridging function but is coordinated via the bis(chelate) mode, and the hydroxyl and carboxyl groups remain vacant. The dissociation of the carboxyl group results in the formation of the tartratogermanate anion with the charge –4.

Two crystalline compounds of germanium(IV) with malic acid (HMal) and 1,10ʹ-phenanthroline (phen) - [Ge(HMal)2(phen)]•pheh•2H2O (I) and [CuCl(phen)2][Ge(OH)(HMal)2] (II) were synthesized for the first time and characterized by elemental analysis, IR-spectroscopy and thermogravimetric analysis. There was elucidated from single-crystal X-ray diffraction that two different forms of Germanium are implemented: Ge4+ (I) and hydrolyzed GeOH3+ (II) to form distorted octahedron and pyramid respectively.

Five heterometallic mixed-ligand cation-anionic complexes perspective for creation of new effective non-toxic drugs [Fe(phen)3]2[Sn2(µ-Tart)2(H2Tart)2]·2H2O (I), [Co(phen)3]2[Sn2(µ-Tart)2(H2Tart)2]·8H2O (II), [Ni(phen)3]2[Sn2(µ-Tart)2(H2Tart)2]·2H2O (III), [Cu(phen)3]2[Sn2(µ-Tart)2(H2Tart)2]·2H2O (IV), [Zn(phen)3]2[Sn2(µ-Tart)2(H2Tart)2]·6H2O (V) with two types of ligands: ditopic polydentate tartaric acid (Tart) and cyclic bidentate 1,10-phenanthroline (phen), p-(Sn) and d-metals (Fe, Co, Ni, Cu, Zn) in their composition were synthesized. The studied complexes I–V are isostructural and contain complex anion [Sn2(µ-Tart)2(H2Tart)2]4-, polyhedrons of two Sn atoms are octahedrons, that are formed by dimeric Sn2(Tart4-)2 fragment and bidentate coordination of two terminal H2Tart2-. All cations in I-V have similar structures [Me(phen)3]2+ with Me = Fe, Co, Ni, Cu, Zn. The present study compares electronic analogues Sn (IV) and Ge (IV) and reveals structural features of the novel tartratostannates and previously obtained tartratogermanates with the same compositional units.

Six morpholine-(iso)thiosemicarbazone hybrids HL1–HL6 and their Cu(II) complexes with good-to-moderate solubility and stability in water were synthesized and characterized. Cu(II) complexes [Cu(L1–6)Cl] (1–6) formed weak dimeric associates in the solid state, which did not remain intact in solution as evidenced by ESI-MS. The lead proligands and Cu(II) complexes displayed higher antiproliferative activity in cancer cells than triapine. In addition, complexes 2–5 were found to specifically inhibit the growth of Gram-positive bacteria Staphylococcus aureus with MIC50 values at 2–5 μg/mL. Insights into the processes controlling intracellular accumulation and mechanism of action were investigated for 2 and 5, including the role of ribonucleotide reductase (RNR) inhibition, endoplasmic reticulum stress induction, and regulation of other cancer signaling pathways. Their ability to moderately inhibit R2 RNR protein in the presence of dithiothreitol is likely related to Fe chelating properties of the proligands liberated upon reduction.

Coordination compounds of essential microelement germanium(IV) with metals (Mg, Na, K, Ca, Cu, etc.) and organic ligands – biocatalysts, antidotes at intoxications and regulators of mineral metabolism in living organism (nicotinic, citric, tartaric, 1-hydroxyethylidendiphosphonic acids, nicotinamide) are synthesized for the first time on the Department of General Chemistry and Polymers of Odessa Mechnikov National University. The favorable activity of the synthesized compounds on cardiovascular and chronic respiratory diseases, senile pneumonia, neuropsychiatric and metabolic disorders, ischemic heart diseases, etc. is described. Thus, the influence of 1-hydroxyethylidendiphosphonatogermanate (medgerm) on CNS, its anxiolytic activity and absence of both hypnotic and myorelaxant effects has been shown. Cardioprotector properties of magnesium hydroxyethylidendiphosphonategermanate as a potential effective and safe drug with the high antihypertensive and antiarrhythmic activity have been found out. The interferoninductive and immunostimulatory activity of germanium(IV) compounds with 1-hydroxyethylidendiphosphonic, nicotinic acids, nicotinamide, pyracetam has been studied. Injection of these drugs (concentration 100-125 μg/ml) causes the 100 % delay of cytopathic action of vesicular stomatitis virus in the cell cultures that demonstrates the ability of compounds to increase essentially cells stability. The perspectives of germanium coordination compounds as interferon inductors and as immune pharmaceuticals for prevention the disbalance of the immune system are reviewed.