DMSO Solubility is Multifactorial

Poorly water-soluble compounds were previously discussed as to the cause of poor water solubility - the large lipophilic greaseballs and the brickdust compounds [15] which are poorly water soluble because of strong intermolecular crystal 

DMSO is much less of a good solvent for the poorly water-soluble brickdust compound because the breaking of a strong inter-molecular crystal lattice is pretty well unchanged whether the solvent is water or DMSO. The breaking of the strong crystal lattice is the primary cause of poor water solubility for the pure brickdust compound. The further a poorly water-soluble compound is into the brickdust camp, the less effective is DMSO as a solvent. 

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