Rice University scientists discover way to make drug manufacturing easier

Rice University scientists have made a breakthrough in drug manufacturing by developing an inexpensive and eco-friendly process for producing diazides, the molecules essential for both drug production and agricultural chemicals. 

The university's team of researchers found the processes of radical ligand transfer and ligand-to-metal charge transfer coupled with iron salts make creating dioxides cheap and better for the environment, according to a press release.

Julian West, an assistant chemistry professor at Rice University, and graduate students Kang-Jie (Harry) Bian and Shih-Chieh Kao helped lead the study, which was published in Nature that highlighted the use of visible light to illuminate the reagents, which in turn allowed them to form diazides under gentler conditions than the current industrial processes that usually involve high heat and corrosive acids.

This method, along with iron-mediated ligand-to-metal charge transfer, allowed the researchers to build similar precursors called vicinal diazides out of common feedstocks. West explained that the process only requires two reagents, iron nitrate and TMS azide, which are readily available in every synthetic lab. 

“Basically, you mix them together in a common solvent and shine light on it. Most every pharmaceutical lab will have LED lights. So basically they’ll just pull things off the shelf,” West said in the release. 

The researchers were inspired by biology in developing the radical ligand transfer process, which is based on the enzymes in human livers, according to West, who added, "we were excited to explore the potential of that one step in the last study."

The lab maximized the process through flow chemistry, running the solution through a looping tube and lighting just that tube. 

“The reaction happens in the part where you shine the light,” West said. “That way we can process more than a single batch, and also have much more control over the amount of light it’s getting by speeding up or slowing down the flow." 

The team believes that their findings will be beneficial for labs that want an easy way to make this kind of product, especially if they don’t have the time to fine-tune these other methods to work well. The research was supported by the Cancer Prevention and Research Institute of Texas, the National Institutes of Health, and the Welch Foundation. Other co-authors include David Nemoto Jr. and Xiao-Wei Chen.