AbstractAttachment of deprotonated nucleosides or of alkylated nucleobases, as their analogues, to zinc was achieved by condensation reactions between TpZn‐OH complexes and nucleobase derivatives. Pyrazolylboratozinc complexes with derivatives of uracil, thymine, guanine, xanthine and hypoxanthine were obtained and characterized by structure determination. In the uracil, thymine, guanine and hypoxanthine derivatives, zinc is bound to the nitrogen atom which bears the proton in the nucleoside. In the xanthine derivatives all three possible bonding modes are realized. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)