651020-47-2Relevant academic research and scientific papers
A direct synthesis of nucleoside analogs homologated at the 3′- and 5′-positions
Schmidt, Juergen,Eschgfaeller, Bernd,Benner, Steven A.
, p. 2937 - 2958 (2007/10/03)
A new route is presented to prepare analogs of nucleosides homologated at the 3′- and 5′-positions. This route, applicable to both the D- and L-enantiomeric forms, is suitable for the preparation of monomeric bis-homonucleosides needed for the synthesis o
Synthesis and properties of oligodeoxynucleotide analogs with bis(methylene) sulfone bridges
Eschgfaeller, Bernd,Schmidt, Juergen G.,Koenig, Marcel,Benner, Steven A.
, p. 2959 - 2997 (2007/10/03)
A convergent, solution-phase synthesis was developed for the bis(methylene) sulfone-bridged oligodeoxynucleotide analogs (SNA) 5′-d(HOCH 2-Tso2Tso2Tso2Cso 2Tso2Tso2Tso2T-CH2SO 3)-3′ (35b) and 5′-d(HOCH2-Tso 2Tso2Tso2Tso2Tso2Tso 2Tso2T-CH2SO2)-3′ (34c) (SO2 corresponds to CH2SO2CH2 instead of OP(=O)(O-)(O). In these, the phosphodiester linkages are replaced by non-ionic bis(methylene) sulfone linkers. The general strategy involved convergent coupling of 3′,5′-bishomo-β -D-deoxyribonucleotide analogs functionalized at the 6′-end (=CH 2-C(5′)) as bromides or mesylates and at the CH 2-C(3′) position as thiols, with the resulting thioether being oxidized to the corresponding sulfone. A single charge was introduced at the terminal CH2-C(3′) position of the octamers to increase their solubility in water. During the synthesis, it became apparent that the key intermediates generated secondary structures through either folding or aggregation in a variety of solvents. This generated unusual reactivity and was unique for very similar structures. For example, although the dimeric thiol d(BzOCH2-Tso2C10C-CH2SH) (14b) was a well-behaved synthetic intermediate, the tetrameric thiol d(TrOCH 2-Tso2Tso2Tso2C-CH2SH) derived from the corresponding thioacetate was rapidly converted to a disulfide by very small amounts of oxidant (28 → 29, Scheme 6), while the analogous tetrameric thiol d(BzOCH2-Tso2TsTso2T-CH 2SH) (26), differing only by a single heterocycle, was oxidized much more slowly (Bz = PhCO, Tr = Ph3C, to = 2-MeC6H 4CO (at N4 of dc)). The sequence-dependent reactivity, well known in many classes of natural products (including polypeptides), is not prominent in natural oligonucleotides. These results are discussed in light of the proposal that the repeating negative charge in nucleic acids is key to their ability to serve as genetic molecules, in particular, their capability to support Darwinian evolution. The ability of 5′-d(HOCH2- Tso2TSo2TSo2Cso2TSo 2TSo2TSo2T-CH2SO3 -)-3′ (35b) to bind as a third strand to duplex DNA was also examined. No triple-helix-forming propensity was detected in this molecule.
