Efficient synthesis of functionalized oligodeoxyribonucleotides with base-labile groups using a new silyl linker

Nucleotides and Nucleic Acids; Oligo- and Polynucleotides

“…33 A phosphoramidate linkage has been introduced into an LNA oligomer (see section 1.2.2) which resulted in oligonucleotides with extraordinarily high resistance to nuclease digestion. 34 An important class of phosphoramidate modification is the morpholino nucleoside (PMO) (5), which have proven to be of particular interest in antisense applications. 35 Oligonucleotides containing PMO modifications have been prepared on a DNA synthesiser using phosphoramidite chemistry, and the resultant oligonucleotides showed good thermal stability with complementary DNA and RNA, albeit slightly reduced compared with DNA.…”

“…4 Use of the new 3 0 -O-silyl loading nucleosides (2) for DNA synthesis has been reported to lead to higher loading of nucleosides on to CPG, with loading of up to 17-29 mmol/g on amino-modified CPG reported. Oligonucleotides are removed from support using 0.2 M Et 3 N d HF at room temperature in 4 h. 5 4-Oxoheptanedioic acid has also been used as a linker between CPG and the first nucleoside, which is removed by treatment with hydrazinium acetate allowing for orthogonal chemistry involving removal of other base protecting groups on solid support. 6 The modified CPG (3) has been used for the synthesis of oligonucleotides as a support that can be removed under mild aqueous conditions (PBS, 90 1C, 2 h).…”

Combinatorial Chemistry Online

“…These reagents could increase the efficiency of introduction of 3 0 -terminal deoxyribonucleoside components into polymer supports and allow the synthesis of unmodified DNA oligomers and also a base-labile modified DNA oligomer. 13 A mild new procedure for preparing protected peptide thioesters, based on Ca 2+ -assisted thiolysis of peptide-Kaiser oxime resin (KOR) linkage, has been described. A model peptide was readily released from the resin by incubating the peptide-KOR at 60°C in mixtures of DMF with n-butanethiol or ethyl 3-mercaptopropionate containing Ca(CH 3 COO) 2 .…”

Synthesis and Properties of Oligonucleotides Incorporating Modified Nucleobases Capable of Watson–Crick‐Type Base‐Pair Formation

“…In this synthesis, a Bu 4 NFlabile linker was developed to release the base-protected oligomers [94,95]. At the 5 0 -end, an amino group was attached to the oligonucleotide chain via a spacer.…”