L44-O is prepared by oxidizing L44 with 40% peracetic acid and the product is recristallized from ethanol.

L44 is prepared by alkylating p-cyclohexylphenol (I) with iosobutene using Aberlyst A 15 as a catalyst. The raw mixture (II) is esterified with nicotinoyl chloride hydrochloride (III). The product is purified by recristallization from ethanol.