Professor Jonathan Sessler

Professor Jonathan Sessler FRSC

Winner: 2022 Dalton Division open award:
Mond-Nyholm Prize for Inorganic 91AV

The University of Texas at Austin

For pioneering work on f-element complexes of expanded porphyrins.

#RSCPrizes

F-element chemistry is like the opera; the followers are few, but they are passionate. This prize will bring attention to this important area of chemistry.

Dr Sessler’s drive to create new anti-cancer drugs reflects his own history as a cancer patient and survivor. His research has led to the development of so-called complexes containing f-elements, including those of the lanthanide series and the early actinides. These are the ‘obscure’ elements at the bottom of the periodic table. Some have interesting luminescent properties, some are radioactive, and others are of interest for their magnetic properties.

Read winner biography

Jonathan L Sessler was born in Urbana, Illinois, USA on 20 May 1956. He received a BS degree (with Highest Honors) in chemistry in 1977 from the University of California, Berkeley. He obtained a PhD in organic chemistry from Stanford University in 1982 (supervisor: Professor James P. Collman). He was a NSF-CNRS and NSF-NATO postdoctoral fellow with Professor Jean-Marie Lehn at L'Université Louis Pasteur de Strasbourg, France. He was then a JSPS visiting scientist in Professor Tabushi's group in Kyoto, Japan.

In September, 1984 Dr Sessler accepted a position as Assistant Professor of 91AV at the University of Texas, Austin, where he is currently the Doherty-Welch Chair. Dr Sessler has authored or co-authored over 860 research publications, written two books (with Dr Steven J Weghorn and Drs Philip A Gale and Won-Seob Cho respectively), co-edited two others, and been an inventor of record on over 80 issued US patents.

From 2008–2019 Dr Sessler served as an Associate Editor for ChemComm. He was a co-founder (with Dr Richard A Miller) of Pharmacyclics Inc, which was acquired by AbbVie for $21 billion in 2015. His lanthanide texaphyrin technology is now the basis for a new company, OncoTex Inc.

In addition to English, Dr Sessler speaks French, Hebrew and Spanish and knows some German, Japanese, and Korean. He is a member of the US National Academy of Inventors, the European Academy of Sciences, and the US National Academy of Sciences.

Q+A

How did you first become interested in chemistry?

My dad, the late Andrew M Sessler, was a theoretical physicist at the Lawrence Berkeley Laboratory. Dinner time conversations would centre around the latest developments in science. My siblings and I were taught early on about the beauty of so-called Fermi problems, a classic exercise in thinking, calculating, and extrapolating. Great fun when we get the right answers. But there was more to my father than trying to teach us to think. He believed in the importance of experiments and set up a back room in our home where my older brother, Dan Sessler, MD, and I could build, explore, and test our crazy ideas. I quickly discovered that mixing up whatever chemicals I could get my hands on could lead to interesting outcomes, such as beautiful smells or homemade explosives. The home lab met its demise after I figured out how to make nitroglycerin and nearly succeeded in blowing myself up. Fortunately, I had my safety goggles on, but the explosion woke up my mother. So, the end of home chemistry experiments. But by then I was hooked.

Who or what has inspired you?

More folks have inspired me than I care to name. The work on f-element complexes of expanded porphyrins, contributions being celebrated with this prize, owes particular credit to Richard A Miller, MD. He was my oncologist back in the late 1970s when I suffered a relapse of Hodgkin's lymphoma while a graduate student at Stanford. (I actually chose that spectacular institution for graduate work because it was right across the street from a world-famous medical centre.) Dr Miller kept challenging me to use porphyrins to cure cancer. He'd ask, "What are you working on for your PhD?" I'd answer, "Models for blood pigments", to which he'd reply, "Can you cure cancer with that?" When my group at The University of Texas succeeded in making the first expanded porphyrin capable of forming stable 1:1 complex with lanthanide cations a few years later, Dr Miller helped launch a company, Pharmacyclics Inc, to develop the technology. We are still working on offshoots of those original ideas even today. Without the inspiration and drive of this great oncologist and the inner fire that probably burns in all cancer survivors, this science would never have developed, or at least not to the extent that it has.

What motivates you?

A personal vendetta against cancer. As a PhD chemist, my overwhelming passion is to create, with the help of what is quite a talented team, one more molecule that can be passed on to medical doctors for clinical testing as an experimental drug.

What has been a challenge for you (either personally or in your career)?

Overcoming early health problems and then the setback of our compound getting to Phase III clinical testing but failing to receive FDA approval.

Why do you think teamwork is important in science?

Science is often highly interdisciplinary. It is thus usually essential to work in teams so as to have access to the expertise needed to advance a project beyond the intellectual confines of a single area. This can greatly improve the impact of the work and provide a teaching and learning opportunity for all team members. Plus, it is usually a lot of fun!