@article {43915, title = {Epalrestat-cytosine cocrystal and salt structures: attempt to control E,Z -> Z,Z isomerization}, journal = {Crystal Growth \& Design}, volume = {17}, year = {2017}, month = {MAY}, pages = {3350{\textendash}3360}, type = {Article}, abstract = {Cocrystallization of the anti-diabetic drug Eparlestat (EPR) with cytosine (CYT) gave EPR--CYT-H+ form I, a salt-cocrystal hybrid structure, salt hydrate (EPR--CYT-H+-H2O, 1:2:1), and non-stoichiometric solvates of EPR--CYT-H+ with EtOH/n-PrOH included in the rhombohedral symmetry voids, referred to as form II. Desolvation of EPR--CYT-H+ form II solvates resulted in an unsolvated form II of EPR--CYT-H+ which was characterized by DSC, TGA and NMR. The carboxylate{\textbullet}{\textbullet}{\textbullet}cytosinium synthon was observed in the salts structure along with the uncommon CYT-H+{\textbullet}{\textbullet}{\textbullet}H+-CYT base pairing in the structures of salt-cocrystal hybrid and salt hydrate. The crystalline forms were characterized by spectroscopic (IR, NMR), thermal (DSC, HSM, TGA), powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SC-XRD) techniques. The intent of using the salt/ salt-cocrystal forms as a means to stop the E,Z  Z,Z isomerization of EPR was not successful in photo-irradiation experiments.}, doi = {10.1021/acs.cgd.7b00322}, author = {Nangia, Ashwini Kumar and Battini, Swapna} }