1. Temperature-dependent carbon-13 nuclear magnetic resonance spectra of tropolone acetate
2. Reactions of Halotropones and Related Compounds
3. Prepared according to Sato, T. Nippon Kagaku Zasshi 1956, 80, 1056. On TLC separation two isomeric tosylates were obtained. The 1H NMR spectrum of the isomer characterized by a lower m.p. (79–81°C) supports the structure previously assigned to 3. 2-Tosyloxy-4-isopropyltropone (3): δH (C6D6) 8.12 (d, J=8.4), 7.42 (d, J(3,5)=1.6, H3), 6.80 (d, J(7,6)=12.2, H7), 6.68 (d, J=8.4), 6.17 (dd, J(6,7)=12.2, J(6,5)=9.7, H6), 6.00 (dd, J(5,6)=9.7, J(5,3)=1.6, H5), 2.05 (heptet, J=6.6, isopropyl methyne), 1.74 (s, tosyl methyl), 0.74 (d, J=6.6, isopropyl methyl groups). Therefore, the isomer with higher m.p. could be assigned structure 4.
4. Synthesis, photochemical decomposition, and tubulin binding of 10-azido-10-demethoxycolchicine and 9-azido-9-demethoxyisocolchicine
5. Covalent reversible binding of alkoxides or thiolates to colchicinoids