Cover illustration: Unit-cell packing diagram for the low-temperature triclinic phase of meso-octamethylcalixpyrrole-dimethyl sulfoxide (1/1), showing portions of two hydrogen-bonded columns extending parallel to the c axis. Within one column, molecules represented in wireframe form are related by the approximate c-glide to the molecules shown in ball-and-stick form. Dashed lines indicate N-HO hydrogen-bonding interactions. See Lynch, Gale, Sessler & Madeiros [Acta Cryst. (2001), C57, 1426-1428].