Synthesis of extended spacer-linked neooligodeoxysaccharides by metathesis olefination and evaluation of their RNA-binding properties

The preparation of linear 1,4-butanediol-linked oligodeoxysugars , and is described which are potential binders to polynucleotides. Various aminodeoxymonosaccharides , , , and which are either allylated at the anomeric center or at C4 were subjected to the metathesis olefination protocol. Depending on the position of allylation E/Z-mixtures of C2-symmetric head-to-head or tail-to-tail homodimers were formed. Among them, saccharides , , and were transformed into the corresponding 1,4-butanediol linked disaccharides by catalytic hydrogenation of the central olefinic double bond and exhaustive deprotection. In order to target extended spacer-linked neooligosaccharides homodimeric aminoglycoside was bisallylated and subjected to cross metathesis conditions using methyl 4-O-allyl daunosamide as reaction partner which yielded two desired trimeric and tetrameric linearly spacer-linked daunosamine derivatives. After hydrogenation and deprotection two additional probes and for nucleic acid binding studies were at hand.