31795-14-9Relevant academic research and scientific papers
Synthesis and properties of RNA analogues having amides as interuridine linkages at selected positions
Rozners, Eriks,Katkevica, Dace,Bizdena, Erika,Stroemberg, Roger
, p. 12125 - 12136 (2007/10/03)
Oligoribonucleotide analogues having amide internucleoside linkages (AM1: 3′-CH2CONH-5′ and AM2: 3′-CH 2NHCO-5′) at selected positions have been synthesized and the thermal stability of duplexes formed by these analogues with complem
An Efficient Synthesis of Enantiomeric Ribonucleic Acids from D-Glucose
Pitsch, Stefan
, p. 2286 - 2314 (2007/10/03)
Enantiomeric oligoribonucleotides ( = ent-RNA) up to a sequence length of thirty-five and consisting of the (L-configurated) nucleosides ent-adenosine, ent-guanosine, ent-cytidine, ent-uridine, and 1-(β-L-ribofuranosyl)thymine were prepared by automated synthesis from appropriate building blocks, carrying a known photolabile 2′-O-protecting group. A simple large-scale synthesis of the new, prefunctionalized L-ribose derivative 5 from D-glucose (Scheme 1) and its straightforward conversion into the five phosphoramidites 28-32 and five solid supports 38-42, respectively, were elaborated (Scheme 4). Within this project, a novel, superior strategy for the synthesis of the 2′-O-{[(2-nitrobenzyl)oxy]methyl}-substituted key intermediates 18-22 by regioselective alkylation of their 5′-O-dimethoxytritylated precursors 13-17 was developed. Furthermore, an improved set-up for the final light-induced cleavage of the 2′-O-protecting groups from the oligonucleotide sequences was designed (Scheme 5 and Fig. 1). The correct composition of all ent-oligoribonucleotides prepared was established by their MALDI-TOF mass spectra. The 1H-NMR-spectroscopic data of a dodecameric ent-RNA sequence was in excellent agreement with the published data of its natural counterpart, synthesized by conventional methods. The known specific cleavage of a tetradecamer sequence by a 35mer ribozyme structure could be reproduced by ent-oligoribonucleotides, synthesized by the presented methods (Fig. 4).
Synthesis, Structure Elucidation and Reactions of trans-Fused 3,6-Anhydro-1,2-O-isopropylidene-α-D-hexofuranoses
Reckendorf, Wolfgang Meyer zu,Schultz, Norbert,Kreimeier, Richard
, p. 337 - 346 (2007/10/02)
Unexpectedly, the reaction of 1,2-O-isopropylidene-5,6-di-O-(p-tolylsulfonyl)-α-D-allofuranose (7) with KCN in ethanol yielded the first trans-fused 3,6-anhydro-hexofuranose 10.Besides by spectroscopic evidence the structure of 10 was proved by transformation to the tosylated acetal 13 which could also be obtained via an independent route.Further reactions of 10 all resulted in opening of the strained ring system yielding acetals (18-22).By blocking the 5-position with the alkali-resistant ether function this cyclization could also be achived by more common reagents like NaH in DMF (32). - By applying this procedure to the corresponding α-D-galactofuranose derivative 41 3,6-anhydro-α-D-galactofuranose 42 could also be obtained albeit in low yield.For comparison purposes the 3,6-anhydro-α-D-gulo derivative 47 was synthesized from easily accessible 44. - Key Words: Carbohydrates / Hexofuranoses / 3,6-Anhydro-D-hexofuranoses
