Reactivity of a Morita‐Baylis‐Hillman adduct derivative bearing a triphenylamine moiety with lysine models

The reactivity of Morita–Baylis–Hillman Adduct (MBHA) derivative 7 was studied with different primary amine derivatives such as n ‐butylamine, Nα‐acetyl‐ L ‐lysine methyl ester, and a poly‐( L ‐lysine) derivative as lysine models to obtain information about the possible reactions in complex protein environments. MBHA derivative 7 reacted with n ‐butylamine or Nα‐acetyl‐ L ‐lysine methyl ester producing monoadducts 9a or 9c , which showed bright emission features in the green region at 526–535 nm with photoluminescence quantum yield values in solutions of 73 % and 51 %, respectively. Based on these results, MBHA derivative 7 can be considered an interesting new fluorogenic probe potentially useful in the labelling of basic amino acid residues. Furthermore, similar to other MBHA derivatives, compound 7 showed the tendency to produce diadducts especially in polar solvents system where specific interactions between the extended aromatic moieties may play a major role.