Co-crystals in the series of 4,5-dihydroxy- 4,5-diphenylimidazolidine-2-thiones

The synthesis of the first co-crystals among 4,5-dihydroxy-4,5-diphenylimidazolidin-2-ones (4,5-dihydroxyimidazolidine- 2-thione + 5-hydroxy-4-methoxy-4,5-diphenyl-1,3-diethylimidazolidine-2-thione) and of the cis isomer of 1,3-diethyl-4,5-dihydroxy- 4,5-diphenylimidazolidine-2-thione through the regiospecific condensation of 1,3-diethylthiourea with 1,2-dioxo-1,2-diphenylethane was implemented; the structure was ascertained by single crystal X-ray diffraction and X-ray phase analysis.