Two C-glucosyl porphyrins are prepared using Ramberg-Backlund and Lindsey methods for the key conversions, and thiosugars are shown to react with perfluorophenylporphyrins.
The synthesis of the northwest quadrant of Altromycin B is described. The preparation of the two epimers at the quaternary carbon of the 6-deoxy-C-altrose moiety in the northwest quadrant is accomplished starting from d-glucose. A key step of our synthetic sequence is the formation of the C-glycoside linkage via the Ramberg-Bäcklund reaction. Two different routes are explored, which differ mainly on the timing of the conversion of glucose to altrose, either before or after the preparation of the C-glycoside. The conformation behavior of variously substituted C-altropyranoside rings is also discussed.
Desymmetrization of bis(phenylsulfonyl)alkenes 1 provides the desired enantiomer of polycyclic ketones rapidly, in high yields, and enantiopure (see below); 1 is also readily available in multigram quantities.
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.