Synthesis and spectroscopic characterization of dimethylgermanium derivatives of dipeptides, crystal structure of dimethylgermanium glycylglycinate and in vivo effects of dimethylgermanium glycylglycinate against murine leukemia P388

Dimethylgermanium derivatives of dipeptides, Me 2 GeAA (H 2 AA = H 2 glygly, H 2 glyala, H 2 glyval, H 2 glyleu, H 2 glymet) have been obtained by the reaction of Me 2 GeBr 2 with H 2 AA in the presence of triethylamine. The crystal structure of Me 2 Geglygly has been determined by single‐crystal X‐ray diffraction. The dipeptide is tridentately coordinated to germanium, which has a distorted trigonal bipyramidal environment. From infrared and Raman data, analogous molecular structures are inferred for the other dimethylgermanium derivatives of dipeptides. 1 H NMR measurements show that Me 2 Geglygly is completely hydrolyzed in aqueous solution to give H 2 glygly and (Me 2 Geo) x . In vivo tests with Me 2 Geglygly showed no toxic or antitumor activity against murine leukemia P388.