Figure 1.

Structures of Tel22 and porphyrins used. (A) Major physiologically relevant structural topologies of Tel22. Red rectangles represent guanines with glycosidic bonds in syn-conformation, while beige rectangles show those with anti-conformations. Yellow and blue circles indicate thymine and adenine bases, respectively. Shown are antiparallel basket structure (left), mixed hybrid (3 + 1) structure of Form 2 (16) (center) and all-parallel propeller loop structure (right). (B) Structures of NMM, NMP and their non-methylated analogues, MIX and PIX. Note, the central N-methyl group, in principle, could be attached to any of the four nitrogens of the porphyrin core, leading to a mixture of four isomers.