Ringing the Changes: Effects of Heterocyclic Ring Size on Stereoselectivity in [(η-CMe)RhCl], [(η-CMe)IrCl] and [Ru(η-cymene)Cl] Complexes of Chiral 3-Amino-1-Azacycles. | LitMetric
Ring size-dependent diastereoselective coordination of unsymmetrical diamines containing one azacyclic nitrogen and one exocyclic nitrogen to [(η-CMe)MCl] cores where M = Rh, Ir and [Ru(η-cymene)Cl] is reported herein. Total stereoselectivity was observed with the six- and seven-membered azacycles, whereas the five-derivative proved poorly selective. All complexes were active for transfer hydrogenation but showed no enantioselectivity with prochiral ketones.
Migratory animals rely on multiple sites during their annual cycles. Deteriorating conditions at any site can have population-level consequences, with long-distance migrants seen as especially susceptible to such changes. Reduced adult survival caused by persecution at non-breeding sites has been suggested a major reason for the catastrophic decline of a formerly abundant, long-distance migratory songbird, the Yellow-breasted Bunting Emberiza aureola.
Tinnitus is a debilitating auditory disorder commonly described as a ringing in the ears in the absence of an external sound source. Sound trauma is considered a primary cause. Neuronal hyperactivity is one potential mechanism for the genesis of tinnitus and has been identified in the cochlear nucleus (CN) and the auditory cortex (AC), where there may be an imbalance of excitatory and inhibitory neurotransmissions.
Phosphorylation of ubiquitin and the ubiquitin-like domain of Parkin, mediated by the kinase PINK1, is essential for the liberation of the E3 ligase from its autoinhibited state. In this issue of Structure, Lenka et al. provide the structural basis for the specificity and stronger Parkin activation by phospho-NEDD8 compared to phospho-ubiquitin.
Climate change is causing avian breeding seasons to start earlier in the temperate zone, leading researchers to explore if this pattern also appears in the timing of nestling ringing dates.
The study uses annual median ringing dates from 1951 to 2020 for 9 bird species in Hungary, aiming to offset some data collection biases.
Results showed significant advancements in breeding dates (by 9-14 days) for some species, like the Black-headed Gull and Great Tit, while others, like the Common Tern and Long-eared Owl, showed no meaningful changes.
