The solvent compounds of sulfamethylpyrimidine were screened in 17 kinds of solvents

such as alcohols

esters and amides

and the sulfamerazine solvates were investigated by powder X-ray diffraction

thermal gravimetric analysis

scanning electron microscopy and Fo

urier transform infrared spectroscopy. The results showed that sulfamerazine can form four solvates with

N

N

-dimethylformamide

N

N

-dimethylacetamide

N

-methylpyrrolidone and dimethylsulfoxide respectively. TGA results showed that they all belong to the type of 1∶1 stoichiometric solvates. SEM results indicated that the morphology of the crystals changed significantly after the formation of the solvates

the morphology of the crystal changed from block shape to sheet and rod crystal. FTIR characterization analysis confirmed that the solvent and the solute molecules formed intermolecular hydrogen bonds in the solvates. The physicochemical properties of the used solvents for the screening were analyzed

and the results showed that the corresponding solvates were easy to form in the solvents with strong hydrogen bond acceptor ability. The packing efficiency of molecules in crystals further confirmed that sulfamerazine form hydrogen bond solvates. The changes of molecular packing

structure synthons and hydrogen bond network before and after the formation of solvates were determined according to the single crystal structures of compounds. Sulfamerazine form Ⅱ and its solvates formed a one-dimensional leader hydrogen bond network. For three solvates

in addition to the hydrogen bond network formed between the molecules of sulfamerazine

another hydrogen atom in the amino group of sulfamerazine was bonded to the oxygen atom of the solvent molecule to form an intermolecular N—H…O hydrogen bond.The results showed that the hydrogen bond played a decisive role in the supramolecular self-assembly process between the solute and the solvent

then affected the formation of solvates.