A study into the cocrystals of different cis-carboxamides with carboxylic acids has analysed the tetrameric motifs that occur. Read the paper while it is free to find out the synthon rules that Cruz-Cabeza and colleagues have come up with:
Synthon preferences in cocrystals of cis-carboxamides:carboxylic acids
Alaina M. Moragues-Bartolome, William Jones and Aurora J. Cruz-Cabeza
CrystEngComm, 2012
DOI: 10.1039/C2CE06241K
This is yet another Hot article from the themed issue on crystal engineering in the pharmaceutical industry that will be published later in the year.