Synthesis and properties of maleopimaric acid amides, imides and imidoamides with arylisoxazole and quinoline fragments

Abstract

The method for maleopimaric acid N-(5-arylisoxazol-3-yl)amides synthesis has been developed by reaction of maleopimaric acid chloride with 3-amine-5-phenyl(4-methylphenyl)isoxazoles. N’-butyl-, N’-(2-hydroxyethyl)imides of maleopimaric acid N-(5-arylisoxazol-3-yl)amides were prepared. Heterocyclic imide – maleopimaric acid N-(quinolin-8-yl) imide was prepared by reaction of maleopimaric acid and 8-aminoquinoline in toluene at reflux in 97.1 % yield. It was established that refluxing of toluene solution of 8-aminoquinoline and maleated rosin, prepared by treatment of rosin with maleic anhydride and containing at least 50 % of maleopimaric acid, leads to the formation of maleopimaric acid N-(quinolin-8-yl)imide in 52.5 % yield (based on weight of maleated rosin). It was found by the methods of IR-, 1H NMR spectroscopy and mass-spectrometry that maleopimaric acid N-(quinolin-8-yl)imide consists of two diastereomeric atropisomers at 1:0.40 ratio. The biological properties of the prepared compounds were studied. It was established that maleopimaric acid N-(5-(4-methylphenyl)isoxazol-3-yl)amide possesses rotatory power (26 mkm-1) and may be used as chiral dopant to nematic LC for preparation of chiral LC-compositions.