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3.
Acylation of 2-methyl-2H-1, 2-benzothiazin-3(4H)-one 1, 1-dioxide 3 with aryl anhydrides in the presence of dimethylaminopyridine occurs regiospecifically to afford 2-methyl-4-arylcarbonyl-2H1, 2-benzothiazin-3(4H)-one 1, 1-dioxides 2a-f . 相似文献
4.
A novel synthesis of the title compounds, representing a new heterocyclic ring system, is described. Chlorosulphonation of 3-methylbenzo[b]thiophene followed by reaction with methylamine gave sulfonamide, 4 . Lithiation of 4 , followed by quenching with carbon dioxide yielded acetic acid, 5 . Cyclodehydration of 5 to benzothienothiazine 6 followed by reaction with aryl isocyanates afforded the desired benzothieno[3,2-e]-1,2-thiazine-4-carboxamides 1a-f. 相似文献
5.
[reaction: see text] Stereospecific 1,2-cis glycosylation of 2-O-vinyl thioglycosides, synthesized from the corresponding alcohols by Ir-catalyzed transvinylation with vinyl acetate, is achieved by iodine-mediated tethering of a range of primary and secondary carbohydrate acceptors, followed by intramolecular aglycon delivery (IAD). The use of such an intramolecular glycosylation strategy furnishes the desired alpha-gluco and beta-manno disaccharides in an entirely stereoselective manner. 相似文献
6.
Chambers C Smith F Williams C Marcos S Liu ZH Hayter P Ciaramella G Keighley W Gribbon P Sewing A 《Combinatorial chemistry & high throughput screening》2003,6(4):355-362
The measurement of intracellular calcium fluxes in real time is widely applied within the pharmaceutical industry to measure the activation of G-protein coupled receptors (GPCRhyp;s), either for pharmacological characterisation or to screen for new surrogate ligands. Initially restricted to G(q) coupled GPCRs, the introduction of promiscuous and chimeric G-proteins has further widened the application of these assays. The development of new calcium sensitive dyes and assays has provided sensitive, homogeneous assays which can be readily applied to high throughput screening (HTS). In this paper we describe the full automation of this assay type using a fluorometric imaging plate reader (FLIPR ) integrated into a Beckman/Sagian system to establish a simple robotic system that is well suited for the current medium throughput screening in this area of lead discovery. Using a recently completed HTS we discuss important determinants for FLIPR based screening, highlight some limitations of the current approach, and look at the requirements for future automated systems capable of keeping up with expanding compound files. 相似文献
7.
The current status of plasma source-mass spectrometry (PS-MS) is reviewed. An overview of interference effects that exist, alternative plasma sources available, and mass spectrometer interface studies is provided. A discussion of current and future development areas in plasma source mass spectrometry is also included. 相似文献
8.
The aldol condensation of 6-alkoxy-2,2-dimethylchromanones 1 or 2 with substituted benzaldehydes in the presence of tetramethylorthosilicate and potassium fluoride affords 6-alkoxy-3-benzylidene-2,2-dimethylchromanones 5-10 while other conventional methods were unsuccessful. 相似文献
9.
Richard D. Chambers Julian F. S. Vaughan Steven J. Mullins 《Research on Chemical Intermediates》1996,22(8):703-715
t-Butylhydroperoxide/butyl-lithium is a good reagent for synthesis of epoxides and diepoxides from polyfluorinated-alkenes and-polyenes. This reagent and calcium hypochlorite both give a novel diepoxide 5 from perfluoro-3,4-dimethyl-2,4-diene 1; diepoxide 5 undergoes a novel rearrangement, at 200°C, to the corresponding 1,4-dioxine derivative 18. Possible mechanisms are discussed. 相似文献
10.
Hulin Li Boyan Zhang Lin Ma Liliu Wu James Q. Chambers 《Transition Metal Chemistry》1995,20(6):552-556
Summary The spectrochemical, electrochemical and electrocatalytic properties of Co[15]aneN4 ([15]aneN4 = 1,4,8,12-tetraazacyclopentadecane) have been investigated. The results show that, in aqueous solution, this compound mainly exists as three species whose axial coordination positions are occupied by water and/or hydroxy ligands; it is marginal whether other substrates such as Cl– and NO
inf3
sup–
interact with the central ion in acid-base solutions. The approximate Pourbaix diagram of CoIII/II[15]ane N4 was determined. There is an electrochemically-induced isomerization between two trans conformational isomers of the Co[15]aneN4 complexes in acid and netural solutions. The Co[15]aneN4 complex has electrocatalytic properties for reduction of nitrate and nitrite only in strong alkaline solution. 相似文献