The reaction of (+)-geldanamycin (5.1 mg, 9.0 μmol) with allylamine (10.0 μL, 0.13 mmol) was dissolved in chloroform (1.5 mL) at room temperature and stirred. The progress of the reaction was monitored by thin-layer chromatography (TLC), and complete conversion of geldanamycin was confirmed after 18 hours. The reaction mixture was subsequently washed with saturated saline, dried over anhydrous sodium sulfate and concentrated under reduced pressure to remove the solvent. Purification was carried out by rapid column chromatography on silica gel, the eluent being a mixed petroleum ether/ethyl acetate solvent, to give the target product as a purple solid (5.3 mg, 99% yield). The product characterization data were as follows: IR (KBr, cm?1) 3464, 3333, 2958, 2929, 2825, 1728, 1691, 1652, 1571, 1485, 1372, 1323, 1189, 1101, 1057; UV (95% ethanol, λmax/nm) 332 (ε=2.0×10?); 1H NMR (CDCl?, 500 MHz) δ 9.14 (s, 1H), 7.28 (s, 1H), 6.93 (bd, J=11.5 Hz, 1H), 6.56 (bdd, J=11.5, 11.0 Hz, 1H), 6.38 (bt, J=6.0 Hz, 1H), 5.94-5.81 (m, 3H), 5.30- 5.24 (m, 2H), 5.17 (s, 1H), 4.82 (bs, 2H), 4.29 (bd, J=10.0 Hz, 1H), 4.21 (bs, 1H), 4.18-4.08 (m, 2H), 3.55 (ddd, J=9.0, 6.5, 2.0 Hz, 1H), 3.43 (ddd, J=9.0, 3.0 , 3.0 Hz, 1H), 3.34 (s, 3H), 3.25 (s, 3H), 2.72 (dqd, J=9.5, 7.0, 2.0 Hz, 1H), 2.63 (d, J=14.0 Hz, 1H), 2.34 (dd, J=14.0, 11.0 Hz, 1H), 2.00 (bs, 3H), 1.78 (d, J= 1.0 Hz, 3H), 1.78-1.74 (m, 2H), 1.74-1.67 (m, 1H), 0.99-0.95 (m, 6H); 13C NMR (CDCl?, 125 MHz) δ 183.8 (18-C), 180.9 (21-C), 168.4 (1-C), 156.0 (7-O?CNH?), 144.6 (17-C), 141.2 (20-C), 135.8 (5-C), 134.9 (2-C), 133.7 (9-C), 132.7 (8-C), 132.5 (3'-C), 126.9 (4-C), 126.5 (3-C), 118.5 (3'-C), 108.8 (19-C), 108.7 (16-C), 81.6 (7-C), 81.4 (12-C), 81.2 (6-C), 72.6 (11-C), 57.1 (6- or 12-OCH?), 56.7 (6- or 12-OCH?), 47.8 (1'-C), 35.0 (13-C), 34.3 (15-C), 32.3 (10-C ), 28.4 (14-C), 22.9 (14-CH?), 12.8 (8-CH?), 12.6 (2-CH?), 12.3 (10-CH?); HRMS (FAB) m/z 586.3120 [M+H]? (calculated value of 586.3129 for C??H??N?O?).
