Researchers devise a quicker, more efficient way to make life-saving molecules

Improved method for creating nucleoside analogues opens the door to discovering countless treatments for everything from cancer to viral diseases.

 U of A researchers Jason Wang, Thirupathi Nuligonda, Gautam Kumar, Dinithi Rajapaksha and Michael Meanwell.

(From left) U of A researchers Jason Wang, Thirupathi Nuligonda, Gautam Kumar, Dinithi Rajapaksha and Michael Meanwell found a new, more efficient way to make nucleoside analogues — a type of molecule that can be used in a wide range of treatments for everything from cancer to viral diseases. (Photo: Supplied)

A team of researchers has found a quicker and more efficient way to create nucleoside analogues, a type of small molecule that can be used in treatments for everything from cancer to viral diseases.

“Nucleoside analogues are among the most important molecules to the advancement of modern medicine,” says Michael Meanwell, Manley and Marian Johnston Professor in the Department of Chemistry and corresponding author of a paper published in Nature Communications describing the new process

“They’re used as antivirals, as cancer therapeutics, in gene therapy. The first two drugs brought to market for treating COVID-19 were both nucleoside analogues.”

Meanwell and his team focused their approach on C4 modified nucleoside analogues, a particular subclass of these molecules. A few antiviral drugs within this subclass are already in clinical trials, highlighting their potential. But the issue is that “these types of nucleosides have been notoriously hard to make,” Meanwell explains.

“Part of it has to do with the chemistry used to make them — it’s mostly based on chemistry from 50, 60 years ago, and the advancements in modern organic chemistry have not yet been fully translated to this field of research.”

Until now, the most common ways to make these modified nucleoside analogues required a process taking anywhere from nine to 16 steps. The new approach requires just five steps. 

Additionally, existing methods were all non-modular, meaning that making different analogues required designing entirely different routes. It would take a month or more to create just one molecular compound in this way. The new process is modular, so multiple analogues can be made at the same time — an advantage for researchers experimenting with different potential therapeutics. 

“By streamlining the process, the barrier now is so much lower to doing drug discovery especially for academic labs working in this area,” says Meanwell. “You can make all the different analogues you want, the chemistry is so much easier, and it reduces the amount of time needed.”

“The breadth of molecules we can make with this one process is truly unprecedented,” he adds.

Nucleosides are fundamental building blocks of DNA, and nucleoside analogues are simply modifications of those structures, explains Meanwell. “They inhibit the same processes associated with cell growth and cell replication that cancer cells and viral diseases take advantage of — by inhibiting them, you can treat those diseases.”

Over the past few decades, nucleoside analogues have been used in treatments for AIDS, Ebola, respiratory syncytial virus (RSV), hepatitis, and many more diseases and infections. A more efficient and effective way to manufacture these powerhouse molecules could pave the way for countless new therapeutics for a vast range of health conditions. 

“It sounds like hyperbole, but they can treat such a broad range of diseases,” says Meanwell. “They really stretch across so many different areas of health.”

“C4 modified nucleoside analogues are so important medicinally because of the wide range of disease pathologies they can intercept,” says lead author Thirupathi Nuligonda. “Now, we have a modular approach to synthesize this important class of nucleoside.” 

The research was funded by Striving for Pandemic Preparedness — The Alberta Research Consortium