Synthesis and properties of calix[4]arene telluropodant ethers as Ag⁺ selective sensors and Ag⁺, Hg²⁺ extractants

• Yang Lu,
• Yuanyuan Li,
• Song He,
• Yan Lu,
• Changying Liu,
• Xianshun Zeng and
• Langxing Chen

Beilstein J. Org. Chem. 2009, 5, No. 59, doi:10.3762/bjoc.5.59

• ; Introduction There is much interest in the development of compounds that selectively respond to specific metal ions for use as ion sensors. As the third generation of supramolecule, benefiting from their three-dimensional structures and easy chemical modification both at the upper- and lower-rims as well as

Review of “Stereochemistry Workbook, 191 Problems and Solutions” by K.-H. Hellwich and C. D. Siebert

• Roald Hoffmann

Beilstein J. Org. Chem. 2009, 5, No. 38, doi:10.3762/bjoc.5.38

• . Molecules have shapes. The logic of isomerism, in all its manifestations, the life-and-death-determining necessity of describing three-dimensional geometry, our representational struggles to do so – these define the beauty of chemistry.

A hydrogen- bonded channel structure formed by a complex of uracil and melamine

• Reji Thomas and
• G. U. Kulkarni

Beilstein J. Org. Chem. 2007, 3, No. 17, doi:10.1186/1860-5397-3-17

• triply hydrogen-bonded melamine-uracil pairs. Three-dimensional packing of melamine and uracil molecules. Molecules under discussion. Crystal structure data. List of intermolecular interactions in melamine-uracil adduct Supporting Information Supporting Information File 22: The data provided represent

• different, in shape and dimension. This clearly indicates the role of the uracil molecule in directing the shape of the channel structure. In conclusion, we have illustrated the molecular recognition process of melamine with nucleobase uracil. We have also established the presence of channels, in the three

• -dimensional supramolecularly hydrogen-bonded structure of this adduct. (a) ORTEP drawing of the asymmetric unit of the 1:1 molecular complex of uracil and melamine. (b) Unique hydrogen bonds present in the complex. (a) Molecular chain formed by melamine and uracil molecules, (b) the aperture formed by the

The vicinal difluoro motif: The synthesis and conformation of erythro- and threo- diastereoisomers of 1,2-difluorodiphenylethanes, 2,3-difluorosuccinic acids and their derivatives

• David O'Hagan,
• Henry S. Rzepa,
• Martin Schüler and
• Alexandra M. Z. Slawin

Beilstein J. Org. Chem. 2006, 2, No. 19, doi:10.1186/1860-5397-2-19

• determines the three dimensional structure of the unit cell. The threo-19 diastereoisomer was prepared by a similar aryl oxidation reaction on a diastereomerically pure sample of threo-13 and this allowed crystallisation of a sample of racemic threo-19. The X-ray structure in Figure 6 shows the molecule in

Colchitaxel, a coupled compound made from microtubule inhibitors colchicine and paclitaxel

• Karunananda Bombuwala,
• Thomas Kinstle,
• Vladimir Popik,
• Sonal O. Uppal,
• James B. Olesen,
• Jose Viña and
• Carol A. Heckman

Beilstein J. Org. Chem. 2006, 2, No. 13, doi:10.1186/1860-5397-2-13

• for three-dimensional cell phenotypes, based on computer-assisted microscopy and sophisticated classification methods, shape data from treated cells were classified by reference to a cell line that became oncogenically transformed over a prolonged course of in vitro culture. Colchicine-treated cells

• ) made from a three-dimensional image. The VROs reconstructed from laser confocal scanning microscopy are shown in Supplemental data. In both untreated and treated cells, the + end 'comets' were concentrated near the cell edge and descended in arc-like patterns toward the substratum. In untreated cells

• , Pittsburgh, PA). The resulting three-dimensional images are displayed in Quickview on Apple Macintosh or Dell PC microcomputers. Microtubule arrangement as visualized by immunofluorescence localization of β-tubulin. Cells were treated with: A) 2 μM Colchitaxel, B) 12 μM Colchitaxel, or C) solvent vehicle