Synthesis and properties of phosphorylated 3'-O-beta-D-ribofuranosyl-2'-deoxythymidine

A strategy was developed for the synthesis of 3'-O-beta-D-ribofuranosyl 2'-deoxythymidine derivatives using three different protecting groups, which allows the synthesis of a phosphoramidite building block for oligonucleotide synthesis. Likewise the 5'-O- and 5''-O-phosphorylated analogues were synthesized and their conformation was determined using NMR spectroscopy.status: publishe

Synthesis and properties of O-beta-D-ribofuranosyl-(1''-> 2')-guanosine-5''-O-phosphate and its derivatives

The efficient synthesis of O-beta-D-ribofuranosyl-(1"-2')-guanosine-5"-O-phosphate and O-beta-D-ribofuranosyl-(1"-->2')-adenosine-5"-O-phosphate, minor tRNA components, have been developed. and their conformational properties were examined by NMR spectroscopy.status: publishe

Synthesis and conformational properties of O-beta-D-ribofuranosyl-(1"-2')-guanosine and (adenosine)-5"-phosphate

The efficient synthesis of Grp and Arp, minor tRNA components, has been developed.status: publishe

Synthesis of RNA containing O-beta-D-ribofuranosyl-(1''-2')-adenosine-5''-phosphate and 1-methyladenosine, minor components of tRNA

tRNA is best known for its function as amino acid carrier in the translation process, using the anticodon loop in the recognition process with mRNA. However, the impact of tRNA on cell function is much wider, and mutations in tRNA can lead to a broad range of diseases. Although the cloverleaf structure of tRNA is well-known based on X-ray-diffraction studies, little is known about the dynamics of this fold, the way structural dynamics of tRNA is influenced by the modified nucleotides present in tRNA, and their influence on the recognition of tRNA by synthetases, ribosomes, and other biomolecules. One of the reasons for this is the lack of good synthetic methods to incorporate modified nucleotides in tRNA so that larger amounts become available for NMR studies. Except of 2'-O-methylated nucleosides, only one other sugar-modified nucleoside is present in tRNA, i.e., 2'-O-beta-D-ribofuranosyl nucleosides. The T loop of tRNA often contains charged modified nucleosides, of which 1-methyladenosine and phosphorylated disaccharide nucleosides are striking examples. A protecting-group strategy was developed to introduce 1-methyladenosine and 5''-O-phosphorylated 2'-O-(beta-D-ribofuranosyl)-beta-D-ribofuranosyladenine in the same RNA fragment. The phosphorylation of the disaccharide nucleoside was performed after the assembly of the RNA on solid support. The modified RNA was characterized by mass-spectrometry analysis from the RNase T1 digestion fragments. The successful synthesis of this T loop of the tRNA of Schizosaccharomyces pombe initiator tRNA(Met) will be followed by its structural analysis by NMR and by studies on the influence of these modified nucleotides on dynamic interactions within the complete tRNA.status: publishe