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A. V. R. RAO ET AL.
was heated to 70 ꢀC and maintained for 3 h. Then it was allowed to cool to room
temperature, after which it was further cooled to 0 ꢀC and maintained for 30 min.
The reaction mixture was filtered, washed with water and ethanol, and dried at room
temperature. Pale yellow solid (1.5 g) was obtained.
Purification (Recrystallization)
In a single-neck flask irinotecan hydrochloride trihydrate (1.5 g), distilled water
(9.6mL), IPA (3.2 mL), and 5% HCl (0.1mL) were added at room temperature. The
reaction mixture was a yellow turbid solution, which was heated to 70ꢀC until a clear
solution was obtained. The reaction mixture was cooled to room temperature
and stirred overnight. The product was collected by filtration, washed with distilled
water, and dried at room temperature to get a pale yellow solid (1.3 g, 94% yield) with
99.8% purity.
[a]D ¼ þ 68.73 (c 1.0, H2O); IR (KBr): nmax 3365, 2935, 1875, 2626, 2542, 1748,
1
1688, 1611, 1565, 1451, 1358, 1191, 1157, 1063, 1037, 1005, 955, 851, 745 cmꢁ1; H
NMR (CDCl3, 300 MHz): d 10.39–10.23 (m, 1H), 8.18 (d, J ¼ 9.1 Hz, 1H), 7.99 (d,
J ¼ 2.2 Hz, 1H), 7.68 (dd, J ¼ 9.1, 2.2 Hz, 1H), 7.32 (s, 1H), 6.54 (s, 1H), 5.44 (s, 2H),
5.34 (s, 2H), 4.40 (d, J ¼ 10.4Hz, 1H), 4.20 (d, J ¼ 12.6Hz, 1H), 3.42 (d, J ¼ 11.1Hz,
2H), 3.28–3.02 (m, 3H), 3.04–2.90 (m, 3H), 2.19 (d, J ¼ 10.2Hz, 2H), 1.98–1.65 (m,
9H), 1.52–1.35 (m, 1H), 1.29 (t, J ¼ 7.3 Hz, 3H), 0.88 (t, J ¼ 7.1 Hz, 3H); 13C NMR
(75 MHz, CDCl3): d 172.49, 156.74, 152.56, 151.53, 149.99, 149.74, 146.16, 145.82,
145.07, 130.91, 128.23, 126.87, 125.78, 118.87, 114.88, 96.60, 72.40, 65.29, 62.02,
49.45, 48.94, 42.92, 42.56, 30.36, 25.69, 25.37, 22.43, 22.24, 21.68, 13.82, 7.80; LC-MS:
m=z (%) 587 (100) [M þ H]þ. Elemental analysis calculated for C33H45N4O12Cl: C,
62.46%; H, 7.17%; N, 8.86%. Found C, 62.24%; H, 6.99%; N, 8.84%.
Please see the Supporting Information, available online, for complete
experimental details.
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