TY - JOUR T1 - CH···O Interactions Are Not the Cause of Trends in Reactivity and Secondary Kinetic Isotope Effects for Enzymatic S<sub>N</sub>2 Methyl Transfer Reactions JF - bioRxiv DO - 10.1101/071043 SP - 071043 AU - Jianyu Zhang AU - Judith P. Klinman Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/09/01/071043.abstract N2 - Compaction matters SN2 substitution represents an important class of reaction for both chemical and biological systems. The ability to assess enzymatic transition state structure within this class of reaction remains a major experimental challenge. Here, we comment on and compare the relative impact of compaction along the axis of reaction to the impact of an orthogonal CH···O hydrogen bonding interaction. The latter is concluded to play a limited role in determining relative reaction rates and secondary KIEs derived from experimental structure-activity correlations. ER -