201158-87-4Relevant academic research and scientific papers
Diastereoselective synthesis of the monosaccharide kedarosamine and incorporation in an analogue of the enediyne kedarcidin chromophore
Vuljanic, Tatjana,Kihlberg, Jan,Somfai, Peter
, p. 279 - 286 (2007/10/03)
Kedarcidin chromophore, as with most enediyne antitumor antibiotics, contains unusual monosaccharide moieties. Synthesis of one of these moieties, the 2,4,6-trideoxy-4-dimethylaminohexose kedarosamine, from D-threonine and incorporation into an analogue of kedarcidin chromophore (1) is described herein. Conversion of D-threonine into allyl ketone 7 and stereoselective reduction by using tetramethylammonium triacetoxyborohydride for intramolecular hydride delivery were key steps in the preparation of kedarosamine. A thioglycoside derivative of kedarosamine (12) was found to be less efficient as a glycosyl donor, whereas a 1-O-acetate (15) gave the desired α-glycoside exclusively in 60-80% yield when treated with borontrifluoride etherate. Use of a Cbz instead of a Fmoc protecting group for the C-4 amino group of kedarosamine was essential for the successful preparation of analogue 1. Finally, dimethylation of the amino group at C-4 of kedarosamine was found to require careful adjustment of the reaction conditions in order to avoid byproduct formation.
