“…According to the HSQC spectrum and a previous report, proton signals at δ H 6.66 (2H, d, J = 8.1 Hz), 7.23 (2H, d, J = 8.2 Hz), together with their corresponding carbon signals at δ C 114.9 and 131.8, respectively, as well as signals at δ H 6.72 (2H, d, J = 8.0 Hz) and 7.05 (2H, d, J = 8.0 Hz) with their corresponding carbon signals at δ C 115.3 and 127.7, respectively, suggested the presence of two symmetrical para -substituted aromatic protons [20]. Besides, signals at δ H 4.48 (1H, d, J = 7.8 Hz), 3.27 (1H, d, J = 9.9 Hz), and 3.98 (1H, d, J = 9.3 Hz), together with their corresponding carbon signals at δ C 40.33 and 57.0, respectively, and a carbonyl carbon signal at δ C 170.8 revealed a pyrrolidine-2-one ring [21]. Furthermore, the existence of a methyl group at δ H 2.98 (3H, s) was noticeable in the 1 H-NMR spectrum.…”