Matching chemical properties to molecular biological activities opens a new perspective on l-ergothioneine.

l-ergothioneine is a low-molecular weight natural product, the chemical structure of which comprises oxygen-, nitrogen- and sulfur-containing functional groups. This gives l-ergothioneine specific physicochemical properties and allows a better understanding of its chemical reactivity, which is primarily due to the 2-thio-imidazole group. Here, a review is provided of how different modes of chemical reactivity account for the reported molecular biological activities of l-ergothioneine.

Short protecting-group-free synthesis of 5-acetylsulfanyl-histidines in water: novel precursors of 5-sulfanyl-histidine and its analogues.

The discovery of a non-enzymatic oxidative introduction of sulfur to the 5-position of histidine is reported, by activation with bromine or NBS followed by reaction with thioacetic acid forming novel 5-acetylsulfanyl-histidine. Complementing the previously developed regioselective oxidative S-introduction to the 2-position of histidine by reaction with cysteine, this surprising finding provides straightforward access in multi-gram quantities to naturally occurring 5-sulfanyl-histidine and its N-methylated analogues, including a hitherto unknown regioisomer of l-ergothioneine.

Simultaneous speciation of selenomethionine and 2-hydroxy-4-methylselenobutanoic acid by HPLC-ICP MS in biological samples.

An analytical method was developed for the simultaneous speciation of selenomethionine (SeMet) and 2-hydroxy-4-methylselenobutanoic acid (NutraSelen), a new SeMet precursor. The compounds could be baseline resolved by ion-pairing reversed-phase HPLC using ICP MS detection. Detection limits of 1 ng mL(-1) (Se content) could be reached.