Compounds of the formula ##EQU1## wherein R.sub.1 is lower alkyl or aryl, R.sub.2 is hydrogen or, together with R.sub.1, ethylene, and R.sub.3 is straight or branched alkyl of 8 to 22 carbon atoms; The compounds have useful therapeutic, dermatological and cosmetic properties.
In this work we report an unprecedented solvent-free approach for the condensation of carboxylicacids with alcohols and amines mediated by carbodiimides, the most widely adopted coupling agents. The solventless procedure enabled fast and high-yielding reactions at either room temperature or under conventional heating despite the use of a catalytic loading of DMAP as the additive (1–5 mol%), far below