Solid-supported azides are commonly generated through direct nucleophilic displacement of appropriately activated supports by the azide ion. This reaction usually proceeds rather sluggishly under harsh conditions. Here, we report that triflyl azide rapidly reacts with a series of amine-functionalized solid supports to generate azide-coated supports under mild conditions. Further, we demonstrate that the "azide coat" allows facile loading of alkyne-functionalized leader nucleoside monomers by click chemistry. Finally, we show that the nucleoside-functionalized supports are suitable for solid-phase oligonucleotide synthetic applications. The approach herein described extends the scope of the amine-azide conversion reaction and may be adaptable for the introduction of azide to diverse amine-terminated solid supports that are not easily accessible by the conventional nucleophilic displacement method.
Study design: Assessment of the potential protective effects of inosine on an animal model of spinal cord injury. Objectives: Our previous studies have demonstrated that inosine can directly protect neurons in vitro from zinc-induced injury and axotomized retinal ganglion cells of rats in vivo. This investigation was carried out to examine the possible protective effects of inosine on spinal cord secondary degeneration. Setting: Institute of Neurosciences, The Fourth Military Medical University, Xi'an, China. Methods: Compressive spinal cord injury (95-g load for 1 min) model was established in rats, and inosine was administrated beginning at different time points (2, 12, or 24 h) after spinal cord injury. Results: Using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) technique and hematoxylin and eosin staining, our study demonstrated that administration of inosine as late as 12 h after injury significantly reduced the total volume of spinal cord degenerative areas and the number of apoptotic cells 3 days following the trauma. Conclusion: Inosine can significantly reduce the spread of secondary degeneration and the cell death following spinal cord injury in adult rats. These findings may find a clinical application in the treatment of acute spinal cord injury.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.