Studies on solvatomorphism of betulinic acid.
Five solvates of betulinic acid with dimethyl sulfoxide (I), methanol (II), ethanol (III), isopropyl alcohol (IV), and 2-butanol (V) have been described in this work. Methods of X-ray crystallography, thermal analysis, and Fourier transform infrared spectroscopy were introduced for solvatomorphic identifications and characterizations. The orientation of isopropenyl and carboxylic groups might differ because of single-bonding rotations. The incorporation of solvents resulted in changes of the crystal symmetry, intermolecular arrangements, stoichiometry, hydrogen bonding interactions, and so on. Adducted solvents contributed most to the stability of crystal lattices and led to the formation of crystalline forms. Solvates II-V with their single-crystal structures determined have been reported for the first time.
['Wang|Xiaoying|X|', 'Gong|Ningbo|N|', 'Yang|Shiying|S|', 'Du|Guanhua|G|', 'Lu|Yang|Y|']
D002626:Chemistry, Pharmaceutical D003460:Crystallization D018360:Crystallography, X-Ray D006860:Hydrogen Bonding D053978:Pentacyclic Triterpenes D012997:Solvents D017550:Spectroscopy, Fourier Transform Infrared D013818:Thermogravimetry D014315:Triterpenes
solvatomorphism betulinic acid solvate DSC FTIR XRPD crystal structure thermogravimetric analysis