Synthesis of (+)-Drim-9(11)-en-8α-ol from Sclareol. -A facile synthesis of the title drimane-type sesquiterpenoid (III) from sclareol diacetate (I) involving ozonolysis and photolysis steps is accomplished. -(VLAD*, P. F.; ARYKU, A. N.; CHOKYRLAN, A. G.; Russ.
Nitrogen-containing drimanes and their biological activity represent a poorly studied area of terpenoid chemistry. Therefore, the synthesis of such compounds is of scientific interest.The preparation of amides 1-4 via Beckmann rearrangement of the Z-and E-isomers of oxime 5 of 14,15-dinorlabd-8(17)-en-13-one (6) was reported earlier [1]. A multi-step synthesis of amide 7 from (-)-sclareol that uses the natural sesquiterpene drim-9,11-en-8D-ol (8) as an intermediate in the synthesis was described [2].Our goal was to study the synthesis of 7 via Beckmann rearrangement of oxime 9 of 11-dihomodriman-8D-ol-12-one (10). Hydroxyketone 10 is readily available and can be obtained from norambreinolide (11) by the method described by us [3]. Oxime 9 was prepared from 10 by reaction with NH 2 OHHCl in a mixture of EtOH and Py. It was a mixture of the Z-and E-isomers according to TLC and 1 H, 13 C, and 15 N NMR spectra. Because the Z-isomer can be easily converted to the E-isomer and the latter is energetically more favorable [1, 4], we used 9 for the reactions as a mixture of its Z-and E-isomers. The Beckmann rearrangement is known to occur stereospecifically as a result of anti-migration of the bulkier radical. Therefore, it was expected that the major product of the Beckmann rearrangement of 9 would be amide 7.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.