Lipase-catalyzed production of novel hydroxylated fatty amides in organic solvent

Pseudozyma (Candida) antarctica lipase B is known to catalyze the direct amidation of carboxylic acids with ammonia in organic solvents. We tested this system for production of primary fatty amides from hydroxy fatty acids including the naturally occurring mono-hydroxy fatty acids, ricinoleic acid (RA) and lesquerolic acid (LQA) and the novel multihydroxy fatty acids, 7,10-dihydroxy-8(E)-octadecenoic acid (DOD) and 7,10,12-trihydroxy-8(E)-octadecenoic acid (TOD). Reactions were performed at temperatures up to 55 °C. Ricinoleic acid and lesquerolic acid were transformed at initial rates comparable to or better than that of oleic acid, a non-hydroxylated substrate. Transformation percentage at 7 days was better than 95% for all substrates except TOD (93.9%). At 55 °C, most reactions approached completion within 1 day. The primary amides of LQA, DOD, and TOD are novel compounds having melting points of 73, 105, and 100 °C, respectively.