The reaction of maleopimaric acid (I) with SOCl2 in benzene produces the corresponding acyl chloride (V), which is then condensed with morpholine (A) by means of Et3N in benzene yielding maleopimaryl morpholide (VI). Finally, (VI) is condensed with ethanolamine (B) in refluxing ethanol.
The reaction of maleopimaric acid (I) with aqueous ammonia and heating at 170 C gives maleopimarimide (II), which by reaction with oxalyl chloride in benzene is converted into the corresponding acyl chloride (III). The reaction of (III) with morpholine (A) in benzene yields maleopimarimidyl morpholide (IV), which is finally condensed with ethanolamine (B) in refluxing methanol.