“…H and13 C NMR spectrum of compound 1 exhibited the presence of an N-methyl group [d H ¼ 2.60 (s) ppm; d C ¼ 42.3 ppm], four methoxy groups [d H ¼ 3.89 (s), 4.00 (s), 4.03 (s), 4.04 (s) ppm; d C ¼ 57.0, 55.87, 55.94, 55.4 ppm], a methylenedioxy group [d H ¼ 6.01 (s) ppm; d C ¼ 101.7 ppm] and four resonance singlet signals in the aromatic region [d H ¼ 6.62 (s), 7.53 (s), 7.53 (s), 7.89 (s) ppm; d C ¼ 95.0, 101.3, 102.8, 103.0 ppm]. Further analysis of the 1 H NMR spectrum revealed the presence of an acetonyl group at C6 due to a methyl signal [d H ¼ 1.98 (s) ppm] together with an AMX coupling system between CH 2 -1 0 [d H ¼ 2.25 (dd, J ¼ 4.3, 14.9 Hz), 2.64 (overlapped) ppm] and 6-H [d H¼ 4.80 (dd, J ¼ 4.3, 10.4 Hz)], and this was confirmed by the correlation between 6-H and the acetonyl methylene protons (CH 2 -1 0 ) in the 1 H, 1 H-COSY spectrum.…”