2′-Deoxy-2′,2′-difluorothymidine analogues for radiolabeling with fluorine-18 and other biomedical applications

A β-Glucosyl Sterol Probe for in situ Fluorescent Labelling in Neuronal Cells to Investigate Neurodegenerative Diseases

A β-glucosyl sterol probe bearing a terminal alkyne moiety for fluorescent tagging enables the investigation of the neuronal and intracellular localization of this class of compounds involved in neurodegenerative diseases. The compound showed localization in the neuronal cells, with marked differences in the uptake and metabolism leading to enhanced persistence with respect to the un-glycosylated sterol analogue. In addition, a different impact was observed towards lysosomes, with the simple sterol probe showing the enlargement of the lysosome structures, while the β-glucosyl sterol was less capable to alter the morphology of this specific organelle.

Chemical Conversion of 5-Fluoromethyl- and 5-Difluoromethyl-Uracil Bases in Oligonucleotides Using Postsynthetic Modification Strategy

This article describes the postsynthetic modification of oligonucleotides (ONs) containing 2'-deoxy-5-fluoromethyluridine (dU^CH2F ) and 2'-deoxy-5-difluoromethyluridine (dU^CHF2 ). Reactions of fully protected and controlled pore glass (CPG)-attached ONs containing dU^CH2F and dU^CHF2 in basic solutions result in deprotection of all protecting groups except for the 4,4'-dimethoxytrityl group, cleavage from CPG, and conversion of the fluoromethyl or difluoromethyl groups to afford the corresponding ONs containing 5-substituted 2'-deoxyuridines. Moreover, the difluoromethyl group can be converted to formyl, oxime, or hydrazone via the postsynthetic conversion of protection- and CPG-free ON containing dU^CHF2 . © 2023 Wiley Periodicals LLC. Basic Protocol 1: Synthesis of fully protected and CPG-attached oligonucleotides containing 2'-deoxy-5-fluoromethyluridine and 2'-deoxy-5-difluoromethyluridine Basic Protocol 2: Postsynthetic modification of fully protected and CPG-attached oligonucleotides containing 2'-deoxy-5-fluoromethyluridine Basic Protocol 3: Postsynthetic modification of fully protected and CPG-attached oligonucleotide containing 2'-deoxy-5-difluoromethyluridine Basic Protocol 4: Postsynthetic modification of protection- and CPG-free oligonucleotide containing 2'-deoxy-5-difluoromethyluridine Support Protocol: Synthesis of 2'-deoxy-5-fluoromethyluridine and 2'-deoxy-5-difluoromethyluridine phosphoramidites.