A highly stereoselective total synthesis of (+)-lycoricidine has been described. The salient features of this synthesis are the one-pot elimination followed by allylation reaction, ring-closing metathesis, stereoselective aziridine formation, Dess-Martin periodinane, and silica gel mediated oxidative ring-opening of aziridine to form alpha,beta-unsaturated ketone (allyl amine) and intramolecular Heck cyclization.
A group of side chain partially saturated tocotrienol analogues, namely tocoflexols, have been previously designed in an effort to improve the pharmacokinetic properties of tocotrienols. (2R,8′S,3′E,11′E)-δ-Tocodienol (1) was predicted to be a high value tocoflexol for further pharmacological evaluation. We now report here an efficient 8-step synthetic route to compound 1 utilizing naturally-occurring δ-tocotrienol as a starting material (24% total yield). The key step in the synthesis is oxidative olefin cleavage of δ-tocotrienol to afford the chroman core of 1 with retention of chirality at the C-2 stereocenter.
I n d i u m ( I I I ) C h l o r i d e / Wa t e r : A V e r s a t i l e C a t a l y t i c S y s t e m JhilluAbstract: Hexose sugars undergo smooth coupling with 1,3-diketones and b-keto esters in the presence of 10 mol% of indium(III) chloride in water at 80 °C to furnish C-furyl glycosides in excellent yields, whereas pentose sugars produce trihydroxyalkyl-substituted furan derivatives with high selectivity. The reactions of cyclic ketones such as cyclohexane-1,3-dione or dimedone with D-glucose in acetonitrile at 80 °C gave the corresponding tetrahydrobenzofuranyl glycosides derivatives.
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.