A convenient method for preparing rigid-core ionic liquid crystals

• Julien Fouchet,
• Laurent Douce,
• Benoît Heinrich,
• Richard Welter and
• Alain Louati

Beilstein J. Org. Chem. 2009, 5, No. 51, doi:10.3762/bjoc.5.51

• , with δ 10.45 (1a) 9.37 (1b), 9.10 (1c), 9.41 (1d) and 8.98 ppm (1e). This dependency is certainly due to the interactions though H-bonding and the charge localisation on the anion. The UV spectra displays typical charge transfer (π–π* or n–n*) transitions in CH2Cl2 at 240 nm (1a ε = 24000 M−1 cm−1

Quinoline based receptor in fluorometric discrimination of carboxylic acids

• Kumaresh Ghosh,
• Suman Adhikari,
• Asoke P. Chattopadhyay and
• Purnendu Roy Chowdhury

Beilstein J. Org. Chem. 2008, 4, No. 52, doi:10.3762/bjoc.4.52

• gradually with chloroform and the change in intensity, as a function of the complex concentration, was linear in each case. Figure 4, for example, shows the effect of dilution on the UV spectra of the 1:1 complex of citric acid with 1. In the 1:1 complex of 1, the absorption at 290 nm is significantly

• of 2 (c = 5.05 × 10−5 M) in different solvents. UV spectra of the complex of 1 with citric acid (c = 1.67 × 10−5 M) and its change of absorbance on dilution (left side); plot of absorbance vs. concentration of the complex of citric acid with 1 (right side). UV spectra of the complex of 1 with D

• -(−)-tartaric acid (c = 1.67 × 10−5 M) and its change of absorbance on dilution (left side); plot of absorbance vs. concentration of the complex of D-(−)-tartaric acid with 1 (right side). UV spectra of the complex of 2 with citric acid (c = 1.67 × 10−5 M) and its change of absorbance on dilution (left side

Phaeochromycins F–H, three new polyketide metabolites from Streptomyces sp. DSS-18

• Jian Li,
• Chun-Hua Lu,
• Bao-Bing Zhao,
• Zhong-Hui Zheng and
• Yue-Mao Shen

Beilstein J. Org. Chem. 2008, 4, No. 46, doi:10.3762/bjoc.4.46

• . Experimental General Precoated TLC plates (silica gel G; Qingdao Marine Chemical Factory, Qingdao, P. R. China). For column chromatography (CC), silica gel (200–300, and 80–100 mesh; Qingdao), silica gel GF254 (Merck), RP-18 gel (Merck), and Sephadex LH-20 gel (Amersham Biosciences) were used. UV Spectra

Synthesis of 2,3,6,7-tetrabromoanthracene

• Christian Schäfer,
• Friederike Herrmann and
• Jochen Mattay

Beilstein J. Org. Chem. 2008, 4, No. 41, doi:10.3762/bjoc.4.41

• (1880), 374 (2770), 354 (3210), 277 (36500), 267 (24900); HRMS (EI): m/z calcd for C14H6Br4: 489.72030; found: 489.71920. UV-spectra of 4 and commercially available anthracene in cyclohexane (9 × 10−5 mol/L). Synthesis of 2,3,6,7-tetrabromoanthracene (4). Acknowledgements Financial support by the

Cimicifoetisides A and B, two cytotoxic cycloartane triterpenoid glycosides from the rhizomes of Cimicifuga foetida, inhibit proliferation of cancer cells

• Li-Rong Sun,
• Chen Qing,
• Yan-Li Zhang,
• Shu-Yu Jia,
• Zhong-Rong Li,
• Shen-Ji Pei,
• Ming-Hua Qiu,
• Michael L. Gross and
• Samuel X. Qiu

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

• rotations were measured with a SEPA-300 polarimeter at room temp. UV spectra were obtained in MeOH with a Shimadzu UV-210 spectrometer and absorption maxima are given in nm. IR spectra were recorded in KBr on a Perkin-Elmer 577 spectrometer. FABMS were run on a VG AUTOSPEC 3000 mass spectrometer. 1H and 13C