Hydrogel Cross-Linking via Thiol-Reactive Pyridazinediones.

Thiol-reactive Michael acceptors are commonly used for the formation of chemically cross-linked hydrogels. In this paper, we address the drawbacks of many Michael acceptors by introducing pyridazinediones as new cross-linking agents. Through the use of pyridazinediones and their mono- or dibrominated analogues, we show that the mechanical strength, swelling ratio, and rate of gelation can all be controlled in a pH-sensitive manner.

lattice adaptivity triggered by solid-gas reactions of cationic group 7 pincer complexes.

The group 7 complexes [M(κ-2,6-(RPO)CHN)(CO)L][BAr] [M = Mn, R = Pr, L = THF; M = Re, R = Bu, L = vacant site] undergo solid-gas reactivity with CO to form the products of THF substitution or CO addition respectively. There is a large, local, adaptive change of [BAr] anions for M = Mn, whereas for M = Re the changes are smaller and also remote to the site of reactivity.

Protein splicing of the three Pyrococcus abyssi ribonucleotide reductase inteins.

An intein is a polypeptide that interrupts the functional domains of a protein, called the exteins. The intein can facilitate its own excision from the exteins, concomitant with the ligation of the exteins, in a process called protein splicing. The alpha subunit of the ribonucleotide reductase of the extreme thermophile Pyrococcus abyssi is interrupted by three inteins in separate insertion sites.