“…Then as olution of zinc(II) acetatedihydrate (39.1 mg, 0.18 mmol, 1equiv) in ethanol (1 mL) was added dropwise, and the resulting mixture was refluxed for 2h ours and stirred at ambient temperature for another 12 hours. The resulting solid was filtered, washed with ethanol (1 mL), and dried in vacuo to yield the desired product as ay ellow solid (34 mg, 34 4.20 (s,2H,4.42 (d,2H,H exo ,2 J H-exo,H-endo = À16.2 Hz), 6.69 (ddd,2H,4 J H-23,H-25 = 1.2 Hz), 6.78 (d, 2H,H -25, 3 J H-25,H-24 = 7.7 Hz), 6.85 (s, 2H, H-1, H-7), 7.08 (s,2H,7.39 (ddd,2H,7.49 (dd,2H,3 C6 6.13, H4 .69, N9 .90, found:C66.07, H4 .95, N 9.80.…”