Structural and antioxidant properties of guanylhydrazinium pyrazine-2-carboxylate

Packiaraj, S.; Kousalya, L.; Pushpaveni, A.; Poornima, S.; Puschmann, H.; Govindarajan, S.

Abstract

In general, molecules with certain functional groups such as amine (-NH2) and carboxyl (-COOH) can promote the growth of co-crystals leading to the formation of supramolecular networks. However, if the differences in the pKa values of the two molecules are large [pKa (base)—pKa (acid)], salts can result instead of ‘real’ co-crystals. Here, we report the formation of such salt by letting pyrazine-2-carboxylic acid (pKa = 2.9) crystallize together with aminoguanidine (pKa = 11.5; high Δpka = 8.6) a nitrogen-rich organic base. The title salt has been prepared by slow evaporation of an equimolar ratio of guanylhydrazine bicarbonate (i.e., aminoguanidine bicarbonate (AgunH.HCO3)) and pyrazine-2-carboxylic acid (Pymca) in aqueous medium. The salt was characterized by IR spectroscopy, powder and single-crystal X-ray diffraction techniques. This material shows enhanced antioxidant activity and this is due to the crucial role of hydrazinic moiety in the aminoguanidinium salt.

Citation

Packiaraj, S., Kousalya, L., Pushpaveni, A., Poornima, S., Puschmann, H., & Govindarajan, S. (2021). Structural and antioxidant properties of guanylhydrazinium pyrazine-2-carboxylate. Journal of Materials Science: Materials in Electronics, 32(6), 7704-7718. https://doi.org/10.1007/s10854-021-05489-2

• Journal Article Type: Article
• Acceptance Date: Feb 4, 2021
• Online Publication Date: Mar 2, 2021
• Publication Date: 2021-03
• Deposit Date: Apr 15, 2021
• Journal: Journal of Materials Science: Materials in Electronics
• Print ISSN: 0957-4522
• Electronic ISSN: 1573-482X
• Publisher: Springer
• Peer Reviewed: Peer Reviewed
• Volume: 32
• Issue: 6
• Pages: 7704-7718
• DOI: https://doi.org/10.1007/s10854-021-05489-2