The role of different nonspecific interactions and halogen contacts in the crystal structure organization of 5-chloroisatoic anhydride

Abstract

The crystal structure of 6-chloro-2,4-dihydro-1H-3,1-benzoxazine-2,4-dione (5-chloroisatoic anhydride), CHClNO, has been determined and analysed in terms of connectivity and packing patterns. The compound crystallizes in the noncentrosymmetric space group Pna2 with one molecule in the asymmetric unit. The role of different weak interactions is discussed with respect to three-dimensional network organization. Molecules are extended into one-dimensional helical arrangements, making use of N-H...O hydrogen bonds and π-π interactions. The helices are further organized into monolayers via weak C-H...O and lone pair-π interactions, and the monolayers are packed into a noncentrosymmetric three-dimensional architecture by C-Cl...π interactions and C-H...Cl and Cl...Cl contacts. A Hirshfeld surface (HS) analysis was carried out and two-dimensional (2D) fingerprint plots were generated to visualize the intermolecular interactions and to provide quantitative data for their relative contributions. In addition, tests of the antimicrobial activity and in vitro cytotoxity effects against fitoblast L929 were performed and are discussed.

A study of the crystal structures, supramolecular patterns and Hirshfeld surfaces of bromide salts of hypoxanthine and xanthine

“…Over the past several decades, non-covalent interactions have been found to play a prominent role in coordination chemistry, materials science and pharmaceutical science (C ˇerny ´& Hobza, 2007;Desiraju, 2013;Perumalla & Sun, 2014). Understanding the role of non-covalent interactions is important in the context of crystal engineering (Aakero ¨y et al, 2010;Pogoda et al, 2018;Cavallo et al, 2016;Desiraju et al, 2013) in order to design solids with desired properties. When it comes to pharmaceutics, active pharmaceutical ingredients (APIs) are known to exist in different solid forms such as salts, co-crystals, solvates, polymorphs and amorphous solids (Aaltonen et al, 2009).…”