The major emphasis during his research career was the application of organic synthesis to biological problems. At the outset, this work focussed on the synthesis and study of enzyme inhibitors and metabolic intermediates. His group devised potent inhibitors of enzymes from a number of classes, in particular the tetrahedral phosphorus derivatives as transition state analog peptidase inhibitors. Dr. Bartlett also addressed issues surrounding the principles of transition state analogy and the influences that structural alterations have on the kinetic and thermodynamic aspects of enzyme-inhibitor interaction. A major area of interest was the shikimate-chorismate biosynthetic pathway; his group synthesized and evaluated intermediates and inhibitors for more than nine enzymes in the sequence. As their last contribution to this field, his group answered the final mechanistic question in the pathway with the determination of the stereochemical course of EPSP synthase by total synthesis of the unstable tetrahedral intermediate.