Seven aliphatic pyrrolidine amides with branched and linear saturated C-15-C-19 acyl moieties were detected in vegetative plant organs of Ipomoea aquatica and Merremia quinquefolia as well as in seeds of M. quinquefolia by GC-MS analysis. One of the compounds was isolated from both species and characterized, as 1-(14-methylhexadecanoyl)pyrrolidine, a new natural product. The presence of 1-hexadecanoylpyrrolidine and 1-octadecanoylpyrrolidine was confirmed by comparison of their GC-MS data with those of synthesized compounds. (C) 1999 Elsevier Science Ltd. All rights reserved.