Tetrazoles frequently replace carboxylic acids in pharmaceutical drugs. However, while the binding modes of tetrazolate and carboxylate anions in amidinium complexes turns out to be similar, the association constant of the former is 2-3 orders of magnitude smaller in DMSO. Crystal structures revealed that the N?H-N hydrogen bonds in amidinium tetrazolates are bent (162° and 169°) and noticeably longer (N?N 2.96 Å) than corresponding hydrogen bonds in both amidinium carboxylates and ammonium tetrazolates. © 2006 American Chemical Society.
|Number of pages||4|
|Publication status||Published - 30 Mar 2006|