Nepetalactone is apparently soluble in DMSO and in Toluene. Should it technically be soluble in Cyclohexane too? If not, is there a good way to get the nepetalactone out of the DMSO/Toluene?
Cyclohexane is immiscible with water and likely DMSO (n-hexane is immiscible with DMSO). Therefore, if your nepetelactone is mixed with or dissolved in DMSO, dilute with cyclohexane and wash several times with cold DI water. DMSO should wash out into the water layer pretty easily.
Adding some water into DMSO solution of nepetalactone will decrease the solubility of nepetalactone and hopefully you get nepetalactone crystal. Try in small sample, add the water dropwisely while magnetically stirring the DMSO solution.