Selective synthesis of novel pyridopyrimido annulated analogues of azepinones from Beckmann rearrangement of corresponding oximes by the 2,4,6-trichloro-1,3,5-triazine and dimethyl formamide reagent

A primary effort in the understanding of the progression of atherosclerotic disease has been methods development for visualization of the atherosclerotic plaque. We introduce a new method for the qualitative analysis of lipids in atherosclerotic fatty streaks which also retains those lipids for biochemical evaluation. An original aspect of the process is the ability to view an entire fatty streak en face, selectively stained for specific lipid classes within the lesion.New Zealand white rabbits were fed a high cholesterol diet(0.15%-0.3% for 14 wks). The aorta was removed and fixed in Carson's phosphate buffered formaldehyde followed by dual staining in the fluorescent dyes Nile red and filipin. Stock solutions of nile red(0.5mg/ml acetone) and filipin(2.5mg/ml dimethyl formamide) were prepared and kept at -20°C; all subsequent steps were at RT. 0.5cm × 1.0cm pieces of aorta were trimmed and adventitia removed. The pieces were then washed 3×15 min in PBS w/o CaMg, soaked in Nile red(NR)/filipin(Fl) stain(100(il NR stock + 200μl Fl stock in 10 ml PBS for 30 min, washed in PBS 3×30 min, rinsed with distilled water, mounted(Crystal Mount, Biomedia) and coverslipped and viewed by fluorescence microscopy.

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Selective Synthesis of Asymmetric Electron-Deficient π-Conjugated Systems

Synfacts ◽

10.1055/s-0037-1612072 ◽

2019 ◽

Vol 15 (02) ◽

pp. 0141

Keyword(s):

Selective Synthesis ◽

Conjugated Systems

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RetroBioCat: Computer-Aided Synthesis Planning for Biocatalytic Reactions and Cascades

10.26434/chemrxiv.12571235.v1 ◽

2020 ◽

Cited By ~ 1

Author(s):

William Finnigan ◽

Lorna J. Hepworth ◽

Nicholas J. Turner ◽

Sabine Flitsch

Keyword(s):

Organic Chemistry ◽

Computer Aided Design ◽

Selective Synthesis ◽

Test Set ◽

Synthesis Design ◽

Computer Aided ◽

Synthesis Planning ◽

Enzymatic Cascades ◽

Target Molecules ◽

Aided Design

As the enzyme toolbox for biocatalysis has expanded, so has the potential for the construction of powerful enzymatic cascades for efficient and selective synthesis of target molecules. Additionally, recent advances in computer-aided synthesis planning (CASP) are revolutionizing synthesis design in both synthetic biology and organic chemistry. However, the potential for biocatalysis is not well captured by tools currently available in either field. Here we present RetroBioCat, an intuitive and accessible tool for computer-aided design of biocatalytic cascades, freely available at retrobiocat.com. Our approach uses a set of expertly encoded reaction rules encompassing the enzyme toolbox for biocatalysis, and a system for identifying literature precedent for enzymes with the correct substrate specificity where this is available. Applying these rules for automated biocatalytic retrosynthesis, we show our tool to be capable of identifying promising biocatalytic pathways to target molecules, validated using a test-set of recent cascades described in the literature.

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Enantioselective Synthesis of Azamerone

10.26434/chemrxiv.7369844.v1 ◽

2018 ◽

Author(s):

Matthew L. Landry ◽

Grace McKenna ◽

Noah Burns

Keyword(s):

Late Stage ◽

Cross Coupling ◽

Enantioselective Synthesis ◽

Selective Synthesis

A concise and selective synthesis of the dichlorinated meroterpenoid azamerone is described. The paucity of tactics for the synthesis of chiral organochlorides motivated the development of unique strategies for accessing these motifs in enantioenriched forms. The route features a novel enantioselective chloroetherification reaction, a Pd-catalyzed cross-coupling between a quinone diazide and a boronic hemiester, and a late-stage tetrazine [4+2]-cycloaddition/oxidation cascade.

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Enantioselective Synthesis of Azamerone

10.26434/chemrxiv.7369844 ◽

2018 ◽

Author(s):

Matthew L. Landry ◽

Grace McKenna ◽

Noah Burns

Keyword(s):

Late Stage ◽

Cross Coupling ◽

Enantioselective Synthesis ◽

Selective Synthesis

A concise and selective synthesis of the dichlorinated meroterpenoid azamerone is described. The paucity of tactics for the synthesis of chiral organochlorides motivated the development of unique strategies for accessing these motifs in enantioenriched forms. The route features a novel enantioselective chloroetherification reaction, a Pd-catalyzed cross-coupling between a quinone diazide and a boronic hemiester, and a late-stage tetrazine [4+2]-cycloaddition/oxidation cascade.

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The Study of Photoreversibility, Photopolimerization and Photocleavage Properties of Polyurethane Coumarin by Means of Electronic Spectrometry and AFM Methods

Revista de Chimie ◽

10.37358/rc.17.7.5732 ◽

2017 ◽

Vol 68 (7) ◽

pp. 1632-1635

Author(s):

Silviu Gurlui ◽

Emil Buruiana ◽

Ioan Gabriel Sandu ◽

Mitachi Strat

Keyword(s):

Uv Irradiation ◽

Room Temperature ◽

Dimethyl Formamide ◽

Photon Excitation ◽

Photochemical Properties ◽

Film State

The spectroscopic and photochemical properties of polyurethane coumarin (PUC) in dimethyl sulf-oxide (DMSO), thetra hydro furan (THF), dimethyl formamide (DMF) and film state were investigated at room temperature under one photon excitation. The results show that under irradiation of l ] 310 nm photodimerization process are increased and under UV irradiation with l[ 260 nm, photocleavage of polymer have been evidenced, too.

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Selective α,α-Dibromination of Arylethanones with Copper(II) Bromide

Letters in Organic Chemistry ◽

10.2174/1570178616666190118152325 ◽

2019 ◽

Vol 16 (9) ◽

pp. 700-704

Author(s):

Jitander K. Kapoor ◽

Loveena Arora ◽

Om Prakash

Keyword(s):

Ethyl Acetate ◽

Heterogeneous System ◽

Side Chain ◽

Selective Synthesis ◽

Aromatic Ketones

Various arylethanones including electron-rich aromatic ketones such as o-hydroxyacetophenone and its p-isomer underwent selective side-chain α,α-dibromination using a heterogeneous system consisting of four molar equivalents of copper(II) bromide in chloroform-ethyl acetate under reflux. This study provides the cleanest method for the selective synthesis of several synthetically useful α,α-dibromoketones which are otherwise difficult to prepare.

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