H ₂ S signals via protein persulfidation. To be regulatory the modification will have to be reversible. Using a new method for persulfide detection, we discover this missing link and show that thioredoxin system acts as depersulfidase in vivo .

Ruthenium porphyrin complexes are active catalysts for the cyclopropanation of styrene derivatives by ethyl diazoacetate with good to very good diastereoselectivity; moderate enantiomeric excesses (34%) are observed using a chiral porphyrin as catalyst.