179002-91-6Relevant academic research and scientific papers
The pyrolysis chemistry of a β-O-4 type oligomeric lignin model compound
Chu, Sheng,Subrahmanyam, Ayyagari V.,Huber, George W.
, p. 125 - 136 (2013)
The pyrolysis behavior of a β-O-4 type oligomeric lignin model compound is studied at a temperature range from 250 °C to 550 °C. Thermogravimetric analysis (TGA) indicates the model compound has three distinct thermal decompositions peaks when a slow temp
Chemoenzymatic total synthesis of a naturally occurring (5-5′)/(8′-O-4-″) dehydrotrimer of ferulic acid
Mouterde, Louis M. M.,Flourat, Amandine L.,Cannet, Molly M. M.,Ducrot, Paul-Henri,Allais, Florent
, p. 173 - 179 (2013/02/23)
The cross-linking of plant cell walls by ferulate dehydrodimerization reactions is well established. Recently, a (5-5′)/(8′-O-4-″) dehydrotrimer of ferulic acid (A) was isolated from alkali extracts of maize bran. Its structure was elucidated on the basis of an extensive structural analysis (UV, MS, 1D and 2D NMR). This first identified ferulic acid dehydrotrimer has revealed that parietal polysaccharide chains can be more extensively cross-linked than has been previously recognized. To produce the (5-5′)/(8′-O-4-″) dehydrotrimer (A) in sufficient high-purity quantities and allow the development of analytical methodologies (e.g., LC/GC, immunohistochemistry) to identify and quantify this peculiar trimer in plant extracts or samples, its first total convergent synthesis has been achieved in 10 steps and in 18 % yield starting from commercially available vanillin by horseradish peroxidase mediated enzymatic aryl-aryl coupling, aldolization/crotonization, and Wittig olefination reactions as the key steps. The first total convergent synthesis of the naturally occurring (5-5′)/(8′-O-4-″) dehydrotrimer of ferulic acid (A) has been achieved in 10 steps and in 18 % yield starting from commercially available vanillin using horseradish peroxidase mediated enzymatic aryl-aryl coupling, aldolization/crotonization, and Wittig olefination reactions as the key steps. Copyright
Model Studies for New o-Nitrobenzyl Photolabile Linkers: Substituent Effects on the Rates of Photochemical Cleavage
Holmes, Christopher P.
, p. 2370 - 2380 (2007/10/03)
Both a model phenacyl and o-nitrobenzyl photolabile linker from the literature along with four new o-nitrobenzyl linkers were prepared and the kinetics of their photolytic cleavage examined in solution. The linkers were prepared by amidation of the carboxylic acid anchoring tether with benzylamine, and the cleavable benzylic substituent was chosen to be either acetic acid or acetamide. Irradiation of the linkers in four solvents (methanol, p-dioxane, and aqueous buffer ± dithiothreitol) at 365 nm and analysis via HPLC afforded kinetic rates of cleavage suitable for comparative purposes. The phenacyl linker was found to cleave slowly under aqueous conditions with no detectable cleavage being observed in the organic solvents. Known o-nitrobenzyl linker 4 showed modest rates of cleavage in aqueous and organic solvents. Incorporation of two alkoxy groups in the benzene ring to generate the veratryl-based linker 13a increased the rate of cleavage dramatically, and introduction of an additional benzylic methyl group (13b) increased the rate of cleavage by an additional 5 fold. Increasing the length of the anchoring carboxylic acid tether from acetic to butyric acid (19) improved the cleavage kinetics modestly in organic media and slightly diminished the rates in water. The amide model linker 21 cleaved from 3 to 7 times faster than the corresponding ester linkage 19. An amide-generating linker 26 was prepared, and its performance to generate photolabile solid supports was briefly examined. The stability of the linker and subsequent cleavage upon photolysis from the support of an isotopically enriched 4-thiazolidinone was demonstrated by gel phase 13C NMR.
Aromatic compounds containing basic and acidic termini useful as fibrinogen receptor antagonists
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, (2008/06/13)
This invention relates to novel compounds containing basic and acidic termini, pharmaceutical compositions containing such compounds, processes for preparing such compounds, and to methods of using these compounds, alone or in combination with other therapeutic agents, for the inhibition of platelet aggregation, as thrombolytics, and/or for the treatment of thromboembolic disorders.
