title: Synthesis and properties of 5'-triphosphoryl 2'-5' oligoadenylates (2-5A), and a general method for synthesis of 3', 5'-bisphosphorylated oligonucleotides.
abstract: 2'-5'-Linked oligoadenylic acid 5'-triphosphates (2-5A) having chain lengths of 2-4 have been synthesized by polymerization of 3'-O-(o-nitrobenzyl)-N-benzoyladenosine 5'-phosphate followed by 5'-triphosphorylation via the imidazolidates. A large scale preparation of 5'-O-phosphoryladenylyl-(2'-5')-adenylyl-(2'-5')-adenosine was performed by the phosphotriester method using 5'-O-monomethoxytrityl-3'-O-(o-nitrobenzyl)-N-benzoyladenosine 2'-O-p-chlorophenylphosphate and 5'-O-phosphorodianilido-3'-O-(o-nitrobenzyl)-N-benzoyladenosine 2'-O-p-chlorophenylphosphate as intermediates. The trimer was also triphosphorylated by the imidazolide method. CD spectra for 5'-mono and triphosphorylated 2'-5' adenylates were measured as well as their UV hypochromicities. This triester method was also applied to the synthesis of 3',5'-bisphosphorylated protected oligoadenylic acids with natural 3'-5' linkages which could be used for further condensations to yield 5'-phosphorylated polynucleotides.
mesh_terms: D000227:Adenine Nucleotides / Q000138:chemical synthesis*; D002942:Circular Dichroism; D007202:Indicators and Reagents; D008722:Methods; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000138:chemical synthesis*; D009843:Oligoribonucleotides / Q000138:chemical synthesis*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000227:Adenine Nucleotides; D007202:Indicators and Reagents; D009841:Oligonucleotides; D009843:Oligoribonucleotides