J. Thiem, H. Wessel
Mar 1, 1985
Citations
0
Influential Citations
5
Citations
Journal
Zeitschrift für Naturforschung B
Abstract
9 By chromium trioxide oxidation and subsequent acid hydrolysis triacetyl emodine (3) was transferred to the aldehyde in a two-step synthesis. In a more favourable sequence 3 was reacted to the bromomethyl derivative 4 and this solvolyzed to the citreoroseine derivative 5. A second NBS reaction gave 8 which after acid hydrolysis led to emodine aldehyde (9). This five-step process proceeded without chromatographic separation in 27% overall yield.