Different forms of antiparallel stacking of hydrogen-bonded antidromic rings in the solid state: polymorphism with virtually the same unit cell and two-dimensional isostructurality with alternating layers.

As a continuation of a systematic structural analysis of 2-hydroxycycloalkanecarboxylic acids and their carboxamide analogs, the effects of antidromic rings [Jeffrey & Saenger (1991). Hydrogen Bonding in Biological Structures. Berlin, Heidelberg: Springer Verlag] upon the layer stacking of cyclopentane and cycloheptane derivatives are compared.

Two polymorphs of a beta-lactam (trans-13-azabicyclo[10.2.0]tetradecan-14-one). Concomitant crystal polymorphism and isostructurality.

Two polymorphs of trans-13-azabicyclo[10.2.0]tetradecan-14-one display a unique example of isostructurality, differing only in the orientation of a given hydrogen bond with respect to the beta-lactam bond.