Total synthesis of indole and dihydroindole alkaloids. XVII. The total synthesis of catharine and vinamidine (catharinine)
作者:James P. Kutney、John Balsevich、Brian R. Worth
DOI:10.1139/v79-270
日期:1979.7.1
(8) or leurosine (7) gave the natural product catharine (3). Potassium permanganate oxidation of 7 or 8 gave 3R-hydroxyvinamidine (19) whereas similar oxidation of 4′-deoxyleurosidine (29) gave the alkaloid vinamidine (4).
Straightforward access to anhydrovinblastine starting from the parent alkaloid leurosine is reported. The key deoxygenation step was first optimized on a model substrate. However, applied to leurosine, only the low-valent Cp2TiCl gave satisfactory results.