“…13C NMR spectrum (δ, ppm, CDCl 3 , HMDS): 212.25 (C2, C6), 49.66 (C1, C7), 37.40 (C3, C5), 29.26 (C4), 23.07 (10), 21.92 (C8, C9). Mass spectrum m/z (% of max peak): 31 (41), 39 (29), 41 (45), 42 (45), 55 (100), 67 (37), 97 (91), 125 60), 163 (23). Found,%: C71.…”