Ok this might be a stupid question, but Im going to ask anyway. Im looking to synthesize isotretinoin from retinol by oxidizing the hydroxy group at the end of the molecule into a carboxilic acid. For this I will use KMnO4, NaOH, and H2O at 25C. My biggest problem is obtaining the retinol, you cant really buy the stuff and I know cod liver oil has a very high concentration of it so I figured it would be a good source. I guess I just need to figure out how to isolate the retinol from the other retinoids in the mixture, that could be really difficult.... anyone have any suggestions? Or would I be able to perform the reaction on the crude cod liver oil and have only the isotretinoin precipitate out?