A one step derivatization of controlled pore glass for oligonucleotide solid-phase synthesis Alain Laurent, a, * Bertrand de Lambert, b Marie-The ´re `se Charreyre, b Bernard Mandrand b and Carole Chaix b, * a Apibio, Zone Astec, 15 rue des Martyrs, 38054 Grenoble Cedex 09, France b Unite ´ Mixte CNRS/bioMe ´ rieux, Ecole Normale Supe ´rieure de Lyon, 46 alle ´e d’Italie, 69364 Lyon Cedex 07, France Received 7 September 2004; revised 24 September 2004; accepted 28 September 2004 Available online 14 October 2004 Abstract—A one step anchoring of various diols on bare controlled pore glass (CPG) support via an adsorption mechanism allowed us to synthesize different (oligonucleotide–3 0 -diol) conjugates with high purity, through standard phosphoramidite chemistry. Diol loading on CPG proved to be efficient and reproducible. This methodology virtually allows the synthesis of any 3 0 -modified oligo- nucleotide, using any reporter molecule containing a diol moiety adsorbed on the CPG. Moreover, vicinal diol as glycol or glycerol enabled the release of some part of oligonucleotide-3 0 -OH. Ó 2004 Elsevier Ltd. All rights reserved. 1. Introduction In the field of solid-phase DNA synthesis, actual strategies used for CPG support derivatization are performed by multi-step reactions, which are time and reagent consuming. Derivatization protocols generally require first CPG functionalization with an amino spacer and secondly the introduction of a labile linker between the support and the nucleoside, which initi- ates DNA synthesis, in order to release the resulting oligonucleotide after the synthesis. 1 Universal supports for DNA synthesis have been described by some authors. For instance, acyclic diol universal linker described by Lyttle and coll. 2 enabled the release of free ODN in solution by a phosphate rearrangement of the linker in ammonia. More recently, Azhayev and Antopolsky 3 proposed a 3-amino-1,2-propanediol based linker, which also rearranged in ammonia, leading to an efficient cleavage of oligonucleotides. In both cases, a phosphate diester function being directly bound to the ODN and bearing a vicinal diol as radical, allowed to induce ODN specific cleavage under basic conditions. We report here on DNA solid-phase synthesis using new diol derivatized CPG supports resulting from a simple one step adsorption reaction of diols on the silica beads. With relation to the diol immobilized on the solid sur- face, the achievement of ODN synthesis followed by deprotection reaction led to the corresponding ODN– 3 0 -O–PO 2 –O–R–OH (R = alkyl, alkyloxy, substituted, etc.). Preliminary amazing results obtained with this strategy demonstrated that a large range of diols can ini- tiate oligonucleotide synthesis. In this paper, we focused more specifically on the adsorption studies of short polyethyleneglycol (PEG) molecules. In the antisense approach, oligonucleotides protected on their 3 0 -position by PEG were reported to be of great interest. 4 The 3 0 protection increased ODN stability in biological fluids. ODN–PEG conju- gates were also described to form stable and stealthy complexes when associated to PEI. 5 In addition, we also investigated on the possibility to elaborate a universal support by adsorption of vicinal diol as glycol or glycerol on CPG to generate a ODN- 3 0 -OH. Preliminary results on this latter strategy are de- scribed herein. This work opens interesting perspectives in the elaboration of new supports for solid-phase synthesis. 0040-4039/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.tetlet.2004.09.167 Keywords: Diol adsorption; Solid-phase synthesis; Oligonucleotide; CPG. * Corresponding authors. Tel.: +33 (0)4 38 786233; fax: +33 (0)4 385374 (A.L.); tel.: +33 (0)4 72728360; fax: +33 (0)4 72728533 (C.C.); e-mail addresses: alain.laurent@apibio.com;carole.chaix@ens-lyon.fr Tetrahedron Letters 45 (2004) 8883–8887 Tetrahedron Letters