Tandem mass spectrometry provides information on the dissociation pathways of gas-phase ions by providing a link between product ions and parent ions. However, there exists a distinct possibility that a parent ion does not dissociate directly to the observed product ion, but that the reaction proceeds through unobserved reaction intermediates. This work describes the discovery and kinetic analy...

a two-year laboratory study on the biology (including self-fertilization) of bulinus truncatus, the intermediate host of schistosoma haematobium, s. bovis and paramphistomum microbotrium in iran, has revealed information on the longevity, reproduction, hatchability rate, hatching time during various months of the year, and growth and mortality rates of this snail. it was found that the reproduc...

Procedures and conditions have been established such that the unstable enzyme-bound flavin intermediate produced in the bacterial luciferase reacti~ can be isolated as approximately 70% of the flavin product, the remaining being the final product, FMN. The structure of the intermediate is proposed to be that of a luciferase-bound 4a,5-dihydroflavin-4a-hydroxide. The intermediate has a half-life...

Stereoselective formation of substituted 1,3-dioxolanes was achieved through an assembly of three components: alkene, carboxylic acid and silyl enol ether. The reaction proceeded via stereospecific generation of a 1,3-dioxolan-2-yl cation intermediate during oxidation of alkene substrates with hypervalent iodine. The stereoselective trapping of the cation intermediate with silyl enol ether comp...

A platinum-catalyzed domino process with intermediate benzopyrylium cations reaches its optimum utility in the formation of 7- and 8-membered rings. With iron(III) chloride, a tetracyclic product is isolated, derived from an oxidative transformation of a metal-carbene intermediate.

Malonyl carba(dethia) N-decanoyl cysteamine methyl esters and novel acetoxymethyl esters were utilised as second-generation probes for polyketide intermediate capture. The use of these tools in vivo led to the characterisation of an almost complete set of biosynthetic intermediates from a modular assembly line, providing a first kinetic overview of intermediate processing leading to complex nat...

Utilizing a late-stage enamine bromofunctionalization strategy, the twelve-step total synthesis of (-)-huperzine Q was accomplished. Furthermore, the first total syntheses of (+)-lycopladines B and C are described. An unprecedented X-ray crystal structure of an unusual epoxyamine intermediate is also reported, and the synthetic application of this intermediate in natural product synthesis is de...

Participants along a production chain which exchange intermediate products on spot markets face price risks, such as the transmission of price fluctuations of the final product. In a real options environment this uncertainty may cause investment reluctance on the different steps of the production chain. This paper analyzes weather a stronger vertical integration along the production chain allow...

Enzyme-mediated reactions may proceed through multiple intermediate conformational states before creating a final product molecule, and one often wishes to identify such intermediate structures from observations of the product creation. In this study, the authors address this problem by solving the chemical master equations for various enzymatic reactions. A perturbation theory analogous to tha...