detritylation of 5'-dimethoxytrityl nucleosides have been quantitatively achieved in minutes at room temperature under aprotic neutral conditions by using stannous chloride. of additional practical consideration and in contrast to protic acids, no depurination was observed with this reagent.

Detritylation of 5'-dimethoxytrityl nucleosides have been quantitatively achieved in minutes at room temperature under aprotic neutral conditions by using stannous chloride. Of additional practical consideration and in contrast to protic acids, no depurination was observed with this reagent.

Novel soluble supports for oligonucleotide synthesis 11a-c have been prepared by immobilizing a 5′-O-protected 3′-O-(hex-5-ynoyl)thymidine (6 or 7) to peracetylated or permethylated 6-deoxy-6-azido-β-cyclodextrins 10a or 10b by Cu(I)-promoted 1,3-dipolar cycloaddition. The applicability of the supports to oligonucleotide synthesis by the phosphoramidite strategy has been demonstrated by assembl...

A novel solid-phase phosphoramidite based oligodeoxynucleotide two-step synthesis method has been developed. Keys to this method are replacement of the 5'-dimethoxytrityl blocking group with an aryloxycarbonyl and the use of N-dimethoxytrityl protection for the exocyclic amines of adenine and cytosine. With these modifications, coupling of each 2'-deoxynucleoside 3'-phosphoramidite to the growi...

The synthesis of N4-benzoyl-5'-O-dimethoxytrityl-2',3'-dideoxy-3'-thiocytidine and its phosphorothioamidite is described for the first time, together with a shortened procedure for the preparation of 5'-O-dimethoxytrityl-3'-deoxy-3'-thiothymidine and its corresponding phosphorothioamidite. The first fully automated coupling procedure for the incorporation of a phosphorothioamidite into a synthe...

3,3(')- Oxybis(dimethoxytrityl chloride) (O-DMTCl) was synthesized as a novel, acid-labile bifunctional protecting reagent. The reactions of O-DMTCl with base-protected ribonucleosides afforded unexpectedly 2('),5(')-cyclic protected ribonucleosides in addition to the expected 3('),5(')-cyclic protected ribonucleosides in good yields.

The 9-phenyland the 9-(p-tolyl)-xanthen-9-yl groups 2a and 2b are recommended as alternatives to the 4,40-dimethoxytrityl group 1 for the protection of the 50-hydroxy functions in oligonucleotide synthesis. 2004 Elsevier Ltd. All rights reserved.

The last few years have seen a tremendous improvement in the methods used to protect hydroxy groups with trityls. However, there is limited work on the selective protection and deprotection of ambident nucleophiles (e.g. amines, alcohols and sulfurs) with trityls and p-methoxy substituted trityls. Methoxysubstituted trityl functions have been used as N-protecting groups in pro-drugs, designed t...