Professor Demchenko was awarded a Ph.D. in organic chemistry by the Russian Academy of Sciences in 1993. He then joined Professor Boons' group at the University of Birmingham (UK) as a BBSRC post-doc. In 1998, he moved to the Complex Carbohydrate Research Center, University of Georgia (USA) as a research associate. In 2001, he joined the faculty at the University of Missouri - St. Louis as an Assistant Professor where he was promoted to Associate Professor (2007) and Professor (2011). In 2014, he was appointed Curators' Distinguished Professor of Chemistry and Biochemistry.
Professor Demchenko has co-authored more than 200 articles and has given more than 150 invited lectures and seminars in the U.S. and abroad. From 2019, he has served as the President of the U.S. Advisory Committee for the International Carbohydrate Symposia. Professor Demchenko is the National Representative of the USA for the International Carbohydrate Organization and the 2020-2021 Chair of the #ACSCARB.