34-membered macrocyclic hexaamine containing two independent N-3 donor sets forms homodinuclear transition metal complexes with cobalt(II), copper(II), and nickel(II). Titration experiments show that the homodinuclear complexes are formed exclusively without formation of mononuclear complexes. Displacements of anions within the copper(II) complexes occur easily upon addition of different anions to the CuCl2 complex. All new complexes are characterized by elemental analysis, IR and UV/VIS spectroscopy, and cyclic voltammetry. The dinuclear Cu(II) complex both in the solution and immobilized in Nafion layer on the electrode undergoes revesible l e reduction independently at each copper center and exhibits catalytic activity towards oxygen reduction.
Seventeen new macrocyclic diamides and tetraamides have been synthesized via amidation reactions of three various methyl phenoxyacetates, readily available from simple dihydroxybenzenes, with alfa,omega-diamines in methanol or ethylene glycol as solvents.
Four bicyclic octaazacryptands and three triaza macrocyclic amines have been synthesized via the reaction of tris(aminoethyl)amine with six rigid aromatic dialdehydes, followed by reduction of the formed Schiff bases with sodium borohydride.
The Suzuki-Miyaura coupling of 4- and 6-halosteroids affords good to excellent yields of potential aromatase inhibitors.While the reaction with 4- and 6-bromo derivatives is catalyzed by Pd(PPh3)2Cl2, the coupling with 6-chloro steroid (chlormadinone acetate) requires the use of Pd(dppb)Cl2 or Pd(dppf)Cl2. The palladium-catalyzed amination of bis(3-bromophenyl) ether of (5_)-cholane-3,24-diol with different polyamines leads to new macrocycles comprising one steroid and one polyamine fragments. Possibility of synthesis of macrocyclodimers containing two steroid and two polyamine fragments have been investigated.
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