Application of bioorthogonal hetero-Diels–Alder cycloaddition of 5-arylidene derivatives of 1,3-dimethylbarbituric acid and vinyl thioether for imaging inside living cells

The fluorescent 5-arylidene derivative of 1,3-dimethylbarbituric acid as a heterodiene reacted with vinyl thioether equipped with a taxol. The cycloadditions rate constants k ₂ were estimated to be in the range from 0.9 × 10 ⁻² M ⁻¹ s ⁻¹ to 1.4 M ⁻¹ s ⁻¹ .