Solvent-free lipase-catalyzed synthesis of a novel hydroxyl-fatty acid derivative of kojic acid.

The aim of this work was the synthesis of a novel hydroxyl-fatty acid derivative of kojic acid rich in kojic acid monoricinoleate (KMR) which can be widely used in the cosmetic and food industry. The synthesis of KMR was carried out by lipase-catalysed esterification of ricinoleic and kojic acids in solvent-free system. Three immobilized lipases were tested and the best KMR yields were attained with Lipozyme TL IM and Novozym 435.

Lipase-catalyzed synthesis of isosorbide monoricinoleate: process optimization by response surface methodology.

A new ester of natural origin was prepared by esterification of 1,4:3,6-dianhydro-d-glucitol (isosorbide) with a long-chain fatty acid (ricinoleic), using immobilized enzyme catalyst in non-solvent system. Renewable raw materials produced from carbohydrates and oil biorefineries were used as basic substances in this study. Response surface methodology (RSM) based on central composite design was used to optimize the main important reaction variables - catalyst concentration (2.

Remarkable observations on triplet-sensitized reactions. the di-pi-methane rearrangement of acyclic 1,4-dienes in the triplet excited state.

Previous studies have led to the conclusion that a large majority of acyclic 1,4-dienes do not undergo photochemical di-pi-methane (DPM) rearrangement under triplet-sensitized irradiation. The results of a detailed analysis of these processes demonstrate that a series of these compounds do indeed undergo highly efficient DPM rearrangement from their triplet excited states when suitable triplet sensitizers are used.