A benzimidazole-based nonheme manganese complex efficiently catalyzes benzylic, aliphatic C-H as well as tertiary C-H oxidation with hydrogen peroxide as the oxidant in the presence of acetic acid as additive. (18)O labeling experiments suggest the reaction may proceed via a high-valent manganese-oxo intermediate.

IGF-1R is an independent prognostic marker for osteosarcoma patients and increased expression of this molecular is correlated with metastasis of osteosarcoma.

Thiostrepton (TSR), often referred as to a parent compound in the thiopeptide family, is a bimacrocyclic member that features a quinaldic acid (QA) moiety-containing side ring appended to the characteristic core system. QA biosynthesis requires an unusual ring-expanding conversion, showing a methyl transfer onto and a rearrangement of the indole part of L-tryptophan to give a quinoline ketone. Herein, we report that the process involves the activities of the radical methyltransferase TsrT, aminotransferase TsrA, dehydrogenase TsrE, and cyclase TsrD. TsrU, a stereospecific oxidoreductase, catalyzes the further conversion of the ketone into an enantiomerically pure S-alcohol. Elucidation of this chemistry, which is common in the biosynthesis of a number of thiopeptides sharing a QA side ring system, facilitates analog generation, as shown by the achievement of region-specific fluorination of thiostrepton with the improved antibacterial activity.

Spontaneous migration of the dislocated rib head following posterior correction surgery resulted in shorter intraspinal rib length and larger uninvaded area. More correction of vertebral translation and rib-vertebrae angle could increase the degree of extraction from the spinal canal immediately after the surgery.

Die Stetter‐Reaktion nutzt eine umgepolte Reaktivität zur katalytischen Bildung 1,4‐difunktionalisierter Produkte. Bei der vorgestellten ersten enzymatischen 1,4‐Addition ermöglicht das ThDP‐abhängige Enzym PigD eine anspruchsvolle asymmetrische intermolekulare Stetter‐Reaktion (siehe Schema).

Chiral bioinspired iron complexes of N 4 ligands based on the ethylenediamine backbone display remarkable levels of enantioselectivity for the first time in the asymmetric epoxidation of a,b-unsaturated ketones using hydrogen peroxide (up to 87% ee) or peracetic acid as oxidant, respectively. Notablely, isotopic labeling with H 2 18O strongly demonstrated that there is a reversible water binding step prior to generation of the significant intermediate.usually derived from the decay of the LFe(IV)=O species or thermodynamic sinks for a number of iron complexes was identified by HR-MS. In addition, the possible mechanisms were proposed and LFe(V)=O species may be the main active intermediate in the catalytic system.

Iron(II) efficiency: The iron complexes of N(4) ligands, derived from proline and benzimidazole, exhibited an unprecedented activity and enantioselectivity for the epoxidation of a variety of di- and trisubstituted enones (see scheme). This system, based on synthetic non-heme iron catalysts, provides ready access to a wide range of epoxyketones of high enantiomeric purity.

A novel series of chiral tetradentate N(4) ligands together with their manganese complexes have been designed and synthesized. With 1 mol % manganese catalyst loading, the enantioselective epoxidation of olefins proceeds with nearly full conversion and enantiomeric excess values of up to 89 % for the first time.