Lipase-catalyzed synthesis of arylaliphatic esters of β- d(+)-glucose, n-alkyl- and arylglucosides and characterization of their surfactant properties

Abstract

β- d(+)-Glucose, n-alkyl-β- d(+)-glucosides, salicin and 1-phenylglucoside were regioselectively acylated at the primary hydroxy group of the sugar moiety with a variety of non-activated arylaliphatic carboxylic acids using lipase B from Candida antarctica in a mainly solid phase in the presence of a small amount of t-butanol in yields up to 71%. The arylaliphatic glucose esters were highly water soluble (15 to >100 g l −1) and showed surface activity. Critical micellar concentrations between 2 and 95 mM and minimal surface tensions around 35–45 mN m −1 were determined. The hydrophilic–lypophilic balance values of arylaliphatic esters from β- d(+)-glucose indicate a use in oil-in-water emulsions or detergents, whereas the n-alkyl- and arylglycosides can be employed as wetting agents or water-in-oil emulsifiers.