. 2021 Feb 16;4(2):824–833. doi: 10.1021/acsptsci.1c00007

Table 1. Structural Scaffolds, Calculated Physicochemical Properties (TPSA and clogD_7.4), Measured Second-Order Rate Constants for the Ligation with TCO, and Blocking Efficiencies of All Investigated Tz-derivatives.

Notes: The distribution coefficient at physiological pH (logD_7.4) and TPSA were calculated using the software Chemicalize. Tetrazines conjugated to DOTA were calculated with chelated trivalent cations, and Tzs with other chelators were calculated with bivalent cations.

Second-order rate constants for the Tz-scaffolds A–L were determined by stopped-flow spectrophotometry (n ≥ 4), monitoring the reaction of representative tetrazines with unsubstituted trans-cyclooctene (TCO) at 25 °C in 1,4-dioxane and with TCO-PEG₄ (modified TCO-5ax–OH, “minor-TCO”) in Dulbecco’s phosphate buffered saline (DBPS) at 37 °C.

n ≥ 3; (see Supporting Information, Tables S1 and S2).

Blocking data from ref (48).

Table 1. Structural Scaffolds, Calculated Physicochemical Properties (TPSA and clogD7.4), Measured Second-Order Rate Constants for the Ligation with TCO, and Blocking Efficiencies of All Investigated Tz-derivatives.

Table 1. Structural Scaffolds, Calculated Physicochemical Properties (TPSA and clogD_7.4), Measured Second-Order Rate Constants for the Ligation with TCO, and Blocking Efficiencies of All Investigated Tz-derivatives.