3-(1-Ethylamino-ethylidene)-1-methyl-pyrrolidine-2,4-dione

Abstract

3-(1-Ethylamino-ethylidene)-1-methyl-pyrrolidine-2,4-dione was obtained as an unexpected product in a three-step synthesis starting with o-nitrobenzoyl sarcosine, acetoacetanilide and ethylamine. The compound showed moderate antibacterial activity against S. aureus and E. coli.

2-Methyl-4-Oxo-4,5-Dihydro-1H-Pyrrole-3-Carboxylic Acid Phenylamide

“…In the course of our ongoing studies on a class of synthetic intermediates, obtained by the acylation of β-enamino amides with N-protected amino acids, we have observed two distinct modes of acid-catalyzed intramolecular cyclization in these compounds, leading to either enaminotetramic derivatives [18] or pyrrolin-4-ones [19]. Our experiments so far have focused on acid-stable protecting groups, which in both modes are retained in the final products, except for one unusual case of 2-nitrobenzoyl protection [20]. It was of interest to check whether an initial removal of the protecting group would change the cyclization mode.…”

“…All reagents and solvents were purchased from Sigma-Aldrich, Darmstadt, Germany, and were used as supplied. Enamino amide 1 was obtained in a quantitative yield by the condensation of ethylamine and acetoacetanilide, following our published procedure [18,20]. NMR spectra were run on a Bruker NEO 400 (400/100 MHz 1 H/ 13 C) spectrometer at BAS-IOCCP-Sofia.…”