C. Guran

1,3,4-Thiadiazole Derivatives. Part 91. Synthesis and BiologicalActivity of Metal Complexes of 5-(2-Aminoethyl)-2-Amino-1,3,4-Thiadiazole

Metal complexes of the title ligand (L) containing Co(II), Ni(II) and Cu(II) were prepared and characterized by elemental analysis, IR, electronic spectroscopy and conductimetry. The new derivatives, possessing the following formulae, CuL2(OH)2, NiL2Cl2, and [Co2LCl4]n showed in vitro antifungal activity against Aspergillus and Candida spp.

Complexes With Biologically Active Ligands. Part 71 Synthesis andFungitoxic Activity of Metal Complexes Containing 1,3,5-tris-(8-Hydroxyquinolino)- Trichlorocyclo-Triphosphazatriene

Complexes containing 1,3,5-tris-(8-hydroxyquinolino)-trichlorocyclotriphosphazatriene, a new cyclophosphazene ligand, and Co(II), Cu(II) and Ni(II) were prepared. The new complexes, having the general formula [MLCl2], [ML2]Cl2, (M=Cu, Co, Ni); [NiLAc], [NiL2Ac]Ac and [ML3]X3 (M=Ni, Co, X=Cl, Ac) were characterised by elemental analysis, electronic-, IR spectroscopy, and electrical conductivity measurements. Some of them inhibited the growth of several fungi species (Aspergillus and Candida spp.)

Functionalized Derivatives of Benzo-Crown Ethers. Part 4.Antifungal Macrocyclic Supramolecular Complexes of Transition MetalIons Acting as Lanosterol-14-α-Demethylase Ihibitors

Poly- and mononuclear metal complexes of 2,3,11,12-bis[4-(10-aminodecylcarbonyl)]benzo-18- crown-6 (L) and Cu(II); Ni(II); Co(II) and Cr(III) have been synthesized and characterized by standard physico-chemical procedures. In the newly prepared complexes the crown moiety oxygen atoms of the macrocyclic host did not generally interact with metal ions, whereas the two amino groups of the ligand always did. Several of the newly synthesized compounds act as effective antifungal agents against Aspergillus and Candida spp., some of them showing activities comparable to ketoconazole, with minimum inhibitory concentrations in the range of 0.3−0.5 μg/mL. The mechanism of antifungal action of these coordination compounds is probably connected to an inhibition of lanosterol-14-α-demethylase, a metallo-enzyme playing a key role in sterol biosynthesis in fungi, bacteria and eukariotes.

Synthesis and antifungal activity of metal complexes containing dichloro-tetramorpholino-cyclophosphazatriene.

Metal complexes of dichloro-tetramorpholino-cyclophosphazatriene containing divalent cations such as Ni(II), Co(II), and Mn(II) have been prepared and characterised by standard physico-chemical procedures (elemental chemical analysis, IR and UV-VIS spectra, conductimetric measurement). The newly synthesised compounds possessed antifungal activity against Aspergillus and Candida spp., some of them showing effects comparable to ketoconazole (with minimum inhibitory concentrations in the range of 2- 30 μg/mL) but being generally less active as compared to the azole. Best activity was detected against C. albicans, and worst activity against A. niger. The mechanism of action of these compounds probably involves inhibition of ergosterol biosynthesis, and interaction with lanosterol-14-α-demethylase (CYP51A1), since reduced amounts of ergosterol were evidenced by means of HPLC in cultures of the sensitive strain A. niger treated with some of these inhibitors.