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An account of the biomimetic total synthesis of three bisorbicillinoids is presented.

A novel silica-supported meta-periodate reagent was utilized for the efficient and facile preparation of aldehydes from vicinal glycols. The oxidative cleavage reagent was effective in facilitating reactions involving vicinal diols that are soluble in aqueous alcohols. Furthermore, the scission products produced from glycol oxidative fission reactions with the gel-supported sodium periodate reagent exhibited high purity.

Alpha-sulfonated ketones were studied.

Experiment was conducted to show that the stereochemical outcome of the intramolecular nitrone-alkene cycloaddition (INAC) reactions of nitrones obtained from 3-O-allyl-D-hexoses is dependent only on the relative configuration at C-2,3. Therefore, 3-O-allyl-D-glucose and -D-altrose afford oxepanes selectively while 3-O-allyl-D-allose and -D-mannose yield tetrahydropyrans selectively.

Abilities to controlthe size and shape of nanocrystals in order to tune functional propertiesare an important grand challenge. Here we report a surfactant self-assemblyinduced micelle encapsulation method to fabricate porphyrin nanocrystalsusing the optically active precursor zinc porphyrin (ZnTPP). Throughconfined noncovalent interactions of ZnTPP within surfactant micelles,nanocrystals with a series of morphologies including nanodisk, tetragonalrod, and hexagonal rod, as well as amorphous spherical particle aresynthesized with controlled size and dimension. A phase diagram thatdescribes morphology control is achieved via kinetically controllednucleation and growth. Because of the spatial ordering of ZnTPP, thehierarchical nanocrystals exhibit both collective optical propertiesresulted from coupling of molecular ZnTPP and shape dependent photocatalyticactivities in photo degradation of methyl orange pollutants. Thissimple ability to exert rational control over dimension and morphologyprovides new opportunities for practical applications in photocatalysis,sensing, and nanoelectronics. [ABSTRACT FROM AUTHOR]

An asymmetric synthesis of dual orexin receptor antagonist MK-6096(1) is described. Key steps for the trans-2,5-disubstituted piperidinyl ether fragment include a biocatalytictransamination, a trans-selective Mukaiyama aldol,and a regioselective pyridyl SNAr process. The pyrimidylbenzoic acid was synthesized via a Negishi coupling and a nitrilehydrolysis. Coupling of the two fragments via a catalytic T3P-mediatedamidation completed the synthesis. Unusual behaviors in the hydrolysisof pyrimidyl benzonitrile and the amide coupling of the pyrimidylbenzoic acid are also described. [ABSTRACT FROM AUTHOR]

Compound 1, a potent and irreversible inhibitor ofβ-lactamases, is in clinical trials with β-lactam antibioticsfor the treatment of serious and antibiotic-resistant bacterial infections.A short, scalable, and cost-effective route for the production ofthis densely functionalized polycyclic molecule is described. [ABSTRACT FROM AUTHOR]

The development of a practical, asymmetric synthesis of the hepatitis C virus (HCV) protease inhibitor MK-5172 (1), an 18-membered macrocycle, is described. [ABSTRACT FROM AUTHOR]

Collision-induced dissociation (CID) tandem mass spectrometry is commonly used for carbohydrate structural determinations. In the CID tandem mass spectrometry approach, carbohydrates are dissociated into fragments, and this is followed by the structural identification of fragments through subsequent CID. The success of the structural analysis depends on the structural correlation of fragments before and after dissociation, that is, structural memory of fragments. Fragments that completely lose the memory of their original structures cannot be used for structural analysis. By contrast, fragments with extremely strong correlations between the structures before and after fragmentation retain the information on their original structures as well as have memories of their precursors' entire structures. The CID spectra of these fragments depend on their own structures and on the remaining parts of the precursor structures, making structural analysis impractical. For effective structural analysis, the fragments produced from a precursor must have good structural memory, meaning that the structures of these fragments retain their original structure, and they must not be strongly affected by the remaining parts of the precursors. In this study, we found that most of the carbohydrate fragments produced by low-energy CID have good memory in terms of linkage position and anomericity. Fragments with ugly memory, where fragment structures change with the remaining parts of the precursors, can be attributed to C ion formation in a linear form. Fragments with ugly memory can be changed to have good memory by preventing linear C ion generation by using an alternative CID sequence, or the fragments of ugly memory can become useful in structural analysis when the contribution of linear C ions in fragmentation patterns is understood. [ABSTRACT FROM AUTHOR]

Water electrolysis assisted by hydrazine has emerged as a prospective energy conversion method for achieving efficient hydrogen generation. Due to the potential coincidence region (PCR) between the hydrogen evolution reaction (HER) and the electro-oxidation of hydrazine, the hydrazine oxidation reaction (HzOR) offers distinct advantages in terms of strategy amalgamation, device architecture, and the broadening of application horizons. Herein, we report a bifunctional electrocatalyst of interfacial heterogeneous Fe 2 P/Co 2 P microspheres supported on Ni foam (FeCoP/NF). Benefiting from the strong interfacial coupling effect between Fe 2 P and Co 2 P and the three-dimensional microsphere structure, FeCoP/NF exhibits outstanding bifunctional electrocatalytic performance, achieving 10 mA cm -2 with low overpotentials of 10 and 203 mV for HER and HzOR, respectively. Utilizing FeCoP/NF for both electrodes in HzOR-assisted water electrolysis results in significantly reduced potentials of 820 mV for 1 A cm -2 in contrast to the electro-oxidation of alternative chemical substrates. The presence of a potential coincidence region makes the application of self-activated seawater electrolysis realistic. The gas production behavior at different current densities in this interesting hydrogen production system is discussed, and some rules that are distinguished from conventional water electrolysis are summarized. Furthermore, a new self-powered hydrogen production system with a direct hydrazine fuel cell, rechargeable Zn-hydrazine battery, and hydrazine-assisted seawater electrolysis is proposed, emphasizing the distinct benefits of HzOR and its potential role in electrochemical energy conversion technologies powered by renewable sources.