Crystallographic Signatures of <i>N</i>⁶-Methoxyadenine Imino Tautomer–Silver Complexes

Abstract

Detailed crystallographic analysis of four silver complexes of N9-benzyl-N6-methoxyadenine, 1, on the basis of three different counteranions and silver ion stoichiometry, is discussed in this article. 1 is a rare tautomer of adenine, which exhibits promutagenic behavior as it partly mimics hydrogen bond donor and acceptor properties of guanine and mispairs with cytosine. Complexes 2 and 4 exhibit discrete Ag2L2 dimer, while complex 3 shows two AgL2 units in addition to a Ag2L2 dimer, all in a head-to tail fashion. Complex 5, on the other hand, shows four AgL2 units coordinated in a head-to-head fashion affording a three-dimensional lattice stabilized by CH···F interactions. Various noncovalent interactions such as hydrogen bonding, CH-π interactions, argentophilic interactions, and Ag-π interactions stabilize these complexes.