76765-79-2

Upstream product

• 996-82-7 sodium diethylmalonate 
• 1940-57-4 9H-fluoren-9-yl bromide 
• 105-53-3 diethyl malonate 
• 86-73-7 9H-fluorene 
• 1689-64-1 9-Fluorenol 

Relevant academic research and scientific papers

Turn-off fluorene-based chemosensor switch to Fe3+: Spectroscopic study, merit parameters, theoretical calculations, and its application in Brazilian ethanol fuel

Development of a new chemosensor is challenging, because it has to deliver sensitiveness, selectiveness, reproducibility, robustness, and the least number of interfering analytes. In this sense coordination chemistry can offer an attractive approach to the problem. Diethyl 2-(9-fluorenyl) malonate (DEFM) was found to be an efficient fluorosensor for Fe3+ ions in ethanolic solutions, showing fluorescence quenching of 99% in the concentration range of 0.1–1.0 μmol L?1, and most importantly, with no effect of interfering ions. Theoretical calculations supported photoelectron transfer (PET) mechanism to explain the fluorescence suppression observed. The method passed several analytical tests and showed the limit of detection and the limit of quantification at 15.56 and 51.85 nmol L?1, respectively. The sensor passed a series of analytical tests and proved to be an attractive low-cost approach for Fe3+ quantification in ethanol fuel.

Turn-off fluorescence chemosensor for iron with Bis(2-aminoethyl)-2-(9- fluorenyl)malonamide functionlized SBA-15

An bis(2-aminoethyl)-2-(9-fluorenyl)malonamide as fluorophore ligand was immobilized onto mesoporous silica type SBA-15 via post synthesis grafting. The obtained material was characterized by small and wide angle X-ray diffraction, N2 adsorption-desorption, Fourier transform infrared spectroscopy, Raman spectroscopy and thermogravimetric analysis that indicate the successful immobilization of the ligand on the surface of mesoporous silica. The sensing ability of the obtained material was studied by addition of the cations Fe 3+, Mg2+, Cr3+, Co2+, Ni 2+, Cu2+, Hg2+ and Zn2+ to water suspensions of the assayed solid. Of all the cations tested addition of Fe 3+ ion to a suspension of this material resulted in the largest decrease in the fluorescence intensity. Turn-off photoluminescence of this material was remarkably observed for iron ions in comparing of the other cations. A good linearity between the fluorescence intensity of this material and the concentration of Fe3+ ion is constructed, which enables it as a fluorescence chemosensor for detecting the Fe3+ ion with a suitable detection limit of 1.35∈×∈10-5. It can be introduced as a novel fluorescent sensor in aqueous solution for a lot of practical applications in chemical, environmental and biological systems.

Cyclic compounds useful in the treatment of dyslipidaemia, atherosclerosis and diabetes, pharamaceutical compositions and preparation process

The present invention relates to cyclic compounds which are of the class of compounds of formula I wherein X and Y represent an oxygen atom and to processes for preparing such compounds. The compounds are useful in the treatment of dyslipidemia, atherosclerosis, and diabetes.