Visible light dye-photosensitised oxidation of pyrroles using a simple LED photoreactor
The photooxidation of pyrrole is typically low yielding due to the absorbance of ultraviolet light, which leads to uncontrolled polymerisation and decomposition. Presented herein is the development of a simple and cost-effective photoreactor utilising Light Emitting Diodes (LEDs) as the light source, and its application to the dye-sensitised oxidation of a range of pyrroles to give corresponding 3-pyrrolin-2-ones. The broader applicability of this approach to the generation of 1O2 is also explored.
Howard, James K.,Rihak, Kieran J.,Hyland, Christopher J. T.,Bissember, Alex C.,Smith, Jason A.
p. 8873 - 8880
(2016/10/03)
Irreversible endo-Selective Diels-Alder Reactions of Substituted Alkoxyfurans: A General Synthesis of endo-Cantharimides
The [4+2] cycloaddition of 3-alkoxyfurans with N-substituted maleimides provides the first general route for preparing endo-cantharimides. Unlike the corresponding reaction with 3H furans, the reaction can tolerate a broad range of 2-substitued furans including alkyl, aromatic, and heteroaromatic groups. The cycloaddition products were converted into a range of cantharimide products with promising lead-like properties for medicinal chemistry programs. Furthermore, the electron-rich furans are shown to react with a variety of alternative dienophiles to generate 7-oxabicyclo[2.2.1]heptane derivatives under mild conditions. DFT calculations have been performed to rationalize the activation effect of the 3-alkoxy group on a furan Diels-Alder reaction.
Foster, Robert W.,Benhamou, Laure,Porter, Michael J.,Bu?ar, Dejan-Kre?imir,Hailes, Helen C.,Tame, Christopher J.,Sheppard, Tom D.
supporting information
p. 6107 - 6114
(2015/04/14)
An unexpected formation of the novel 7-oxa-2-azabicyclo[2.2.1]hept-5-ene skeleton during the reaction of furfurylamine with maleimides and their bioprospection using a zebrafish embryo model
An unexpected intramolecular cyclization during the reaction of furfurylamine with maleimides is reported as a novel strategy for the efficient green synthesis of the 7-oxa-2-azabicyclo[2.2.1]hept-5-ene skeleton. Under the same reaction conditions, 7-oxabicyclo[2.2.1]hept-5-enes were synthesized when furfurylamine was N-protected by the acetyl group. Both types of bicycloheptenes were screened using the zebrafish model system for genetics and developmental biology. The Royal Society of Chemistry 2013.
Puerto Galvis, Carlos E.,Kouznetsov, Vladimir V.
p. 407 - 411
(2013/02/25)
Antibacterial activity of N-phenylmaleimides, N-phenylsuccinimides and related compounds. Structure-activity relationships
The antibacterial activity of several phyllanthimide analogs were investigated by the Minimum Inhibitory Concentration Method (MIC) against E. coli and S. aureus. It was found that maleimides were approximately 30 times more active than succinimides indicating that the cyclic imido double bond is an important factor related to the activity. Electron-donor and electron-withdrawing substituents in the aromatic ring of N-phenylmaleimides decrease the activity of these compounds indicating the possibility of steric effects. The distance between the aromatic and the imido rings when separated by methylene groups does not affect the antibacterial activity.