Evaluation of 3-ethoxy-1,2,4-dithiazoline-5-one (EDITH) as a new sulfurizing reagent in combination with labile exocyclic amino protecting groups for solid-phase oligonucleotide synthesis
| Autor: | Shaji T. George, Biji Jacob-Samuel, Jeanne C. Dignam, Steven H. Gray, Godwin W. Fong, Michael Y.-X. Ma, Linhui Li |
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| Rok vydání: | 1997 |
| Předmět: |
chemistry.chemical_classification
Base (chemistry) Oligonucleotide Oligonucleotides Molecular Probe Techniques Biology Oligonucleotide synthesis Combinatorial chemistry Thiazoles Ammonium hydroxide chemistry.chemical_compound chemistry Biochemistry Reagent Phosphodiester bond Genetics Alkoxy group Protecting group Research Article |
| Zdroj: | Nucleic Acids Research. 25:3590-3593 |
| ISSN: | 1362-4962 0305-1048 |
| DOI: | 10.1093/nar/25.18.3590 |
| Popis: | 3-ethoxy-1,2,4-dithiazoline-5-one (EDITH) was recently introduced as an efficient sulfurizing reagent for solid-phase oligonucleotide synthesis. The successful syntheses were performed using standard base protecting groups (i.e. benzoyl for A and C, isobutyryl for G), which required deprotection in concentrated ammonium hydroxide at 55 degrees C for 15-18 h. We have explored the possibility of using EDITH in combination with fast deprotection chemistry(e.g. Expedite Chemistry using tert -butylphenoxy acetyl as a base protecting group). Surprisingly, poor synthesis performance was observed when syntheses were conducted with EDITH, Expedite Chemistry and standard synthesis cycle (i.e. Coupling-Thio-Cap). Potential G modification seemed to be the source of incompatibility since sequences containing no G or carrying isobutyryl- protected G residues could be synthesized with high efficiency. However, the deleterious G modification can be readily eliminated by inserting a capping step before the sulfurization reaction. Oligomers prepared with the Coupling-Cap-Thio-Cap cycle contained few phosphodiester contaminants as measured by31P-NMR, anion-exchange HPLC and MALDI-TOF mass spectrometry. In addition to reducing deprotection time, this new combination also provides a mild method for the preparation of certain phosphorothioate oligomers that may be sensitive to prolonged ammonia treatment (e.g. thioated RNAs). |
| Databáze: | OpenAIRE |
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