Abstract

PLATA-VARGAS, Eduardo et al. Synthesis of Metforminium Succinate by Melting. Crystal Structure, Thermal, Spectroscopic and Dissolution Properties. J. Mex. Chem. Soc [online]. 2017, vol.61, n.3, pp.197-204. ISSN 1870-249X.

The reaction by melt mixing at 220 °C of the antihyperglycemic drug metformin hydrochloride 1 with dehydrated sodium succinate yields efficiently the organic salt [MET]2[SUC] 2 (H-MET+= metforminium and SUC2- = succinate). Solid state CPMAS NMR 13C spectroscopy experiments, powder X-ray diffraction and FT-IR results support the formation of the pharmaceutical salt 2 in good yields. Besides, the charged-assisted hydrogen bonding interactions of type N-H…-O(carboxylate) were thoroughly analyzed by single crystal X-Ray diffraction techniques. Thus, the pharmaceutical salt 2possesses considerable thermal differences when compared to the pure starting reagents. In addition, intrinsic dissolution rate expe riments in buffered aqueous solutions at pH= 6.8 showed a sustained-release behavior of the drug in 2 with a constant value of K int = 0.885 mg/min * cm2.

Keywords : Diabetes; Metformin; X-ray structures; ssCPMAS NMR ¹³C; Melting; Succinate; mechanochemistry; green chemistry.