Crystal structure of betulinic acid-DMSO solvate

The crystal structure of betulinic acid-DMSO (1 : 1) solvate has been determined. The betulinic acid, [3 beta-hydroxy-lup-20(29)-en-28-oic acid, C30H48O3] is considered as a promising natural agent for the clinical treatment for various types of cancer. Crystals of betulinic acid for X-ray structural analysis were grown from a DMSO-water (9 : 1, v/v) solution. Betulinic acid-DMSO (1 : 1) solvate crystallizes in the orthorhombic, P2(1)2(1)2(1) space group, Z = 4. The unit cell parameters are as follows: cell lengths a = 6.9417(2) angstrom, b = 13.8559(5) angstrom, c = 31.6232(10) angstrom, V = 3041.63(17) angstrom(3). Betulinic acid molecules are hydrogen bonded to DMSO molecules. The weak intermolecular hydrogen bonds and van der Waals interactions are present in the crystal structure. The crystal and molecular structures of betulinic acid-DMSO solvates are discussed with reference to betulin and betulinic acid derivatives.