ポリグリセロールやその脂肪酸エステルの合成と油脂ゲル化作用

抄録

Polyglycerols are oligomers of glycerol (glycerin). Their fatty acid esters (PGE) are generally dispersible in water and soluble in oil. They are widely using in food additives, cosmetic materials and toiletries as surfactants. We are interested in developing chemically modified linear and cyclic polyglycerols and their esters that have a single polymerization degree and fine structure. In this study, we synthesized authentic standards of linear and cyclic polyglycerol with well-defined structures and degrees. Linear oligomers polymerized from 2 to 10 were synthesized by means of a convergent approach based on the coupling of tosylate with protected glycerol units in good yields. Cyclic polyglycerols polymerized from 3 to 6 were also synthesized by intramolecular cyclization conditions.
Triglyceryl di-, tri-, and tetra-fatty acid esters were also synthesized from common substrate as new prominent gelators. These triglyceryl esters were capable of gelling up a wide variety of oils. A comparison of the gelation ability of structurally related compounds clarified that the introduction of alkyl chains of suitable length is required for effective gelation. The measurement of transmittance at 500 nm could be the appraisal standard for the aggregation level.