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

• Published in: Acta crystallographica. Section E, Crystallographic communications Crystallographic communications, 2022-06, Vol.78 (6), p.652-659
• Main Authors: Sathya, Udhayasuriyan, Nirmalram, Jeyaraman Selvaraj, Gomathi, Sundaramoorthy, Dhivya, Durairaj, Jegan Jennifer, Samson, Abdul Razak, Ibrahim
• Format: Article
• Language: English
• ISSN: 2056-9890; 2056-9890
• DOI: 10.1107/S2056989022005278

Two new crystalline salts, namely, hypoxanthinium bromide monohydrate, C 5 H 5 N 4 O + ·Br − ·H 2 O ( I ) and xanthinium bromide monohydrate, C 5 H 5 N 4 O 2 + ·Br − ·H 2 O ( II ), were synthesized and characterized by single-crystal X-ray diffraction technique and Hirshfeld surface analysis. The hypoxanthinium and xanthinium cations in salts I and II are both in the oxo-N(9)–H tautomeric form. The crystal packing of the two salts is governed predominantly by N–H...O, N–H...Br, C–H...Br and O–H...Br interactions described by R 2 3 (9) and R 2 2 (8) synthons. The crystal packing is also consolidated by carbonyl...π interactions between symmetry-related hypoxanthinium ( HX + ) cations in salt I and xanthinium cations ( XA + ) in salt II . The combination of all these interactions leads to the formation of wave- and staircase-like architectures in salts I and II , respectively. The largest contributions to the overall Hirshfeld surface are from Br...H/H...Br contacts (22.3% in I and 25.4% in II ) .