Heterosynthons, Solid Form Design and Enhanced Drug Bioavailability.

Starting from a molecular pharmacophore, which is a marker of drug action in medicinal molecules, we propose that the heterosynthon, a supramolecular synthon between unlike functional groups, plays an analogous role in the design and discovery of high bioavailability drugs. The heterosynthon could provide a more efficient and economical route to novel drugs.

Crystal engineering in 2021: interactions, structures, properties.

The articles in the chemistry and crystal engineering section of published from 2021 onwards continue to deal with themes like , and taken in the broadest sense.

Reply to the 'Comment on "Trimorphs of 4-bromophenyl 4-bromobenzoate. Elastic, brittle, plastic"' by J. J. Whittaker, A. J. Brock, A. Grosjean, M. C. Pfrunder, J. C. McMurtrie and J. K. Clegg, , 2021, , DOI: 10.1039/D0CC07668F.

Crystals that differ in their molecular constitution may yet share the same mechanical property, such as plastic deformation, because they are equivalent in a supramolecular sense.

Synthetic Approaches to Halogen Bonded Ternary Cocrystals.

Higher cocrystal synthesis depends acutely on a knowledge of supramolecular synthons. We report three synthetic approaches towards ternary halogen bonded cocrystals that illustrate specificity and generality. Electrophilicity/nucleophilicity differences are needed among alternative sites of halogen bond formation.

Quaternary and quinary molecular solids based on structural inequivalence and combinatorial approaches: 2-nitro-resorcinol and 4,6-di-chloro-resorcinol.

A synthetic strategy for the formation of stoichiometric quaternary and non-stoichiometric quinary solids is outlined. A series of 2-nitro-resorcinol-based quaternary cocrystals were developed from binary precursors in two conceptual stages. In the first stage, ternary solids are synthesized based on the structural inequivalence at two recognition sites in the binary.