Automated synthesis of oligodeoxyribonucleoside methylphosphonates having [N-(3-aminoprop-1-yl)-N-(2-hydroxyethyl)-2-aminoethyl] phosphate or methylphosphonic acid at the 3' end using a modified controlled pore glass support.
To provide a solid support for automated synthesis of 3'-(aminoalkyl)-modified oligonucleoside methylphosphonates, controlled pore glass beads were functionalized with a protected N-(3-aminoprop-1-yl)-N-(2-hydroxyethyl)-2-aminoethyl ester of succinic acid. This "Aha-CPG" was used for automated synthesis of oligo-2'-deoxyribonucleoside methylphosphonates having either of two distinct 3' terminal modifications. If the first coupling to the beads was of a base-protected 5'-(dimethoxytrityl)-2'-deoxyribonucleoside 3'-(beta-cyanoethyl N,N-diisopropylphosphoramidite) synthon, then, upon completion of methylphosphonate oligomer synthesis and deprotection, the 3'-[N-(3-aminoprop-1-yl)-N-(2-hydroxyethyl)-2-aminoethyl] phosphate] derivative of an oligonucleoside methylphosphonate was produced and was shown to be a stable structure which affords a primary alkylamine group suitable as a site for further conjugations. If the first coupling was of a 5'-(dimethoxytrityl)-2'-deoxyribonucleoside 3'-(N,N-diisopropylmethylphosphonamidite) synthon, the initial product of synthesis and deprotection underwent a spontaneous, regiospecific ester cleavage in aqueous solution to produce an oligonucleoside methylphosphonate 3'-(methylphosphonate). An application of the Aha-CPG to the synthesis of rhodamine-conjugated oligonucleoside methylphosphonates is described in a companion paper [Thaden, J. and Miller, P. S. (1993) Bioconjugate Chem., preceding paper in this issue].
Thaden
J
J
Department of Biochemistry, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Maryland 21205.
Miller
P S
PS
D001483:Base Sequence; D002855:Chromatography, Thin Layer; D005449:Fluorenes / Q000138:chemical synthesis*; D005898:Glass; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000138:chemical synthesis*; D009943:Organophosphorus Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D014320:Triphenylmethyl Compounds / Q000138:chemical synthesis*
D005449:Fluorenes; D009838:Oligodeoxyribonucleotides; D009943:Organophosphorus Compounds; D014320:Triphenylmethyl Compounds; C085092:N-(N-((9-fluorenylmethoxy)carbonyl)-3-aminoprop-1-yl)-N-(O-(4,4'-dimethoxytrityl)-2-oxyethyl)-N-(O-(3-carboxylpropionyl)-2-oxyethyl)amine; C032627:methylphosphonic acid