Reaction behavior of molybdocene dichloride towards ribonucleosides and ribonucleoside monophosphates: Rare example of sugar coordination

The coordination behavior of Cp2Mo2+ towards the ribonucleosides and ribonucleoside monophosphates uridine, adenosine, cytidine, guanosine, 5′-UMP, 5′-AMP, 5′-CMP and 5′-GMP has been studied in solution in the range 4 ⩽ pD ⩽ 9 using NMR spectroscopy. The ribonucleosides were found to bind Cp2Mo2+ exclusively through the ribose moiety giving rise to the chelate complexes [Cp2Mo(urd-O2′,O3′)], [Cp2Mo(ade-O2′,O3′)], [Cp2Mo(cyd-O2′,O3′)], and [Cp2Mo(gua-O2′,O3′)]. The ribonucleotides form three types of complex with Cp2Mo2+ in neutral solution, namely N,PO-macrochelates, PO,O3′-coordinated species as well as O2′,O3′-chelates, while at pD 9 only sugar coordination is observed.