Synthesis and characterization of transition metal-vitamin B13 complexes mixed with a co-vitamin

The synthesis and structural characterization of mixed vitamin-metal complexes are reported. A complex bearing two vitamins (B3 and B13) on the same metal centre, nicotinamide(orotato) nickel(II) pentahydrate, has been prepared and characterised by single-crystal X-ray diffraction methods. A complex of Cr(III) with vitamins C and B13, bis(ascorbato) orotatochromium(III) dihydrate, has been isolated and its nature investigated by means IR, (CNMR)-C-13, API-ES and thermogravimetric measurements. Theoretical calculations have been performed to propose a structure in accord with results obtained.