“…Note: 81 is a known compound (apovincamine, CAS No. 4880-92-6), 44,45 and this procedure converting vincamine to 81 was adapted from the literature. 44 1 H NMR: (600 MHz, CDCl 3 ) δ 7.47 (d, J = 7.7 Hz, 1H), 7.23 (d, J = 8.3 Hz, 1H), 7.17 (td, J = 7.1, 1.1 Hz, 1H), 7.13 (td, J = 7.2, 0.9 Hz, 1H), 6.14 (s, 1H), 4.17 (s, 1H), 3.95 (s, 3H), 3.38 (dd, J = 13.9, 6.2 Hz, 1H), 3.27 (td, J = 11.7, 5.5 Hz, 1H), 3.03 (m, 1H), 2.70−2.60 (m, 2H), 2.54 (dd, J = 16.4, 3.4 Hz, 1H), 2.00−1.86 (m, 2H), 1.75 (m, 1H), 1.52 (d, J = 13.7 Hz, 1H), 1.42 (dt, J = 13.2, 2.9 Hz, 1H), 1.06− 0.98 (m, 4H).…”