Fidaxomicin, also known as tiacumicin B or lipiarmycin A3, is a novel macrocyclic antibiotic that is used in hospitals for the treatment of Clostridium difficile infections. This natural product has also been shown to have excellent bactericidal activity against multidrug-resistant Mycobacterium tuberculosis. In spite of its attractive biological activity, no total synthesis has been reported t...

We studied antegrade concealed conduction of atrial extrastimuli (A2) that blocked in the atrioventricular (AV) node in eight subjects, using a third extrastimulus (A3), coupled at decreasing coupling intervals to A2. Three A1-A2 intervals were tested in each subject: late (just shorter than AV nodal effective refractory period), intermediate, and early (just longer than atrial functional refra...

The reaction of fully reduced soluble bovine heart cytochrome oxidase with O2 at 173K was investigated by low-temperature optical and e.p.r. spectroscopy, and the kinetics of the reaction were analysed by non-linear optimization techniques. The only e.p.r. signals seen during the course of the reaction are those attributable to low-spin cytochrome a3+ and CuA2+. Quantitative analysis of e.p.r. ...

A new dimeric orthopalladated complex was synthesized via reaction of 2,3-dimethoxy benzaldehyde oxime with palladium chloride and lithium chloride in methanol as solvent and sodium acetate as base at room temperature. The catalytic activity of this dimeric [Pd{C6H2(-CH=NOH)-(OMe)2-2,3}(µ-Cl)]2 complex as an efficient, air, and moisture tolerant catalyst was investigated in Mizoroki–Heck cross ...

A new dimeric orthopalladated complex was synthesized via reaction of 2,3-dimethoxy benzaldehyde oxime with palladium chloride and lithium chloride in methanol as solvent and sodium acetate as base at room temperature. The catalytic activity of this dimeric [Pd{C6H2(-CH=NOH)-(OMe)2-2,3}(µ-Cl)]2 complex as an efficient, air, and moisture tolerant catalyst was investigated in Mizoroki–Heck cross ...

Adenosine (ADO) is a potent bronchoconstrictor in allergic patients and has been shown to increase the release of histamine from human lung tissues. Antagonists of ADO A1 and A2A receptors are not effective in attenuating these effects. Therefore, involvement of ADO A3 receptors in the bronchoconstrictor and/or inflammatory effects have to be considered. Eosinophils also play a pivotal role in ...

1. In the presence of both CO and O2, ox heart cytochrome c oxidase forms a 607 nm-peak intermediate distinct from both the cytochrome a2+a3 2+CO and the cytochrome a3+a3 2+CO ('mixed-valence') CO complexes. 2. This aerobic CO compound is stable towards ferricyanide addition, but decomposed on treatment with ferric cytochrome a2 ligands such as formate, cyanide and azide. 3. Addition of formate...