Starting from 5-ethyldihydrofuran-2(3H)-one (9) we prepared aldehydes (6 and 7) which, in a [4+2] cycloaddition reactions with the tryptamine derivative (8) gave, as a final step, compounds (13 and 22) having D-seco-pseudoaspidospermane skeleton. We synthesized (±)-20-epiibophyllidine (4) via the benzoate ester (15) or the mesylate (17) of alcohol (14) which had been obtained from 13, while the catalytic hydrogenation of 22 led to (±)-ibophyllidine (3) via full epimerization, cyclization and reduction steps in one operation.
|Number of pages||16|
|Publication status||Published - Apr 1 2007|
ASJC Scopus subject areas
- Analytical Chemistry
- Organic Chemistry