Derivatives of orthoacids. II. The preparation of olefins from 1,2-diols

1964 ◽  
Vol 17 (12) ◽  
pp. 1392 ◽  
Author(s):  
G Crank ◽  
FW Eastwood
Keyword(s):  
Carbon Dioxide ◽  
Allyl Alcohol ◽  
Ethyl Formate ◽  
Diethyl Maleate ◽  
Compound I ◽  
Reaction Sequence ◽  
Ethyl Orthoformate ◽  
Derivatives Of

Ethyl orthoformate reacted with pinacol to form 2-ethoxy-4,4,5,5-tetramethyl-1,3-dioxolan (I) which decomposed on heating to yield ethanol, carbon dioxide, and 2,3-dimethylbut-2-ene. When subjected to the same reaction sequence diethyl- D-tartrate, diethyl-meso-tartrate, meso-1,2-diphenylethane-1,2-diol, and cis-cyclo-hexane-1,2-dial underwent specific cis-elimination to yield diethyl fumarate, diethyl maleate, cis-stilbene, and cyclohexane respectively. Glycerol, butane-1,2,4-trial, and pentane-1,2,5-triol formed polymers which decomposed to yield allyl alcohol, but-1-en-4-ol, and pent-1-en-5-ol respectively. Pyrolysis of the monoformyl esters of cis-cyclohexane-1,2-diol, glycerol, butane-1,2,4-triol, and pentane-l,2,5-trio1 gave the respective products enumerated above whereas the monoformyl ester of pinacol yielded pinacolone. When compound (I) was heated in the presence of p-toluenesulphonic acid it gave ethyl formate, pinacolone, 2,3-dimethylbutadiene, and water.

Derivatives of orthoacids. IV. Acid-catalysed thermal eliminations and baseinduced eliminations of some 2-Ethoxy-1,3-dioxolans

1968 ◽  
Vol 21 (8) ◽  
pp. 2013 ◽  
Author(s):  
JS Josan ◽  
FW Eastwood
Keyword(s):  
Carbon Dioxide ◽  
Carboxylic Acid ◽  
Carbonyl Compound ◽  
Ethyl Formate ◽  
Preparative Method ◽  
Derivatives Of

A series of phenyl substituted 2-ethoxy-1,3-dioxolans (orthoformates) has been prepared and their stereochemistry assigned. When heated in the presence of a carboxylic acid they underwent a stereospecific cis elimination to form the corresponding olefins, carbon dioxide, and ethanol. Provided that one 4 or 5 position in these dioxolans was unsubstituted, they reacted with butyllithium through elimination of the elements of ethyl formate and the formation of a carbonyl compound. The eliminated portion was always converted by the butyllithium into nonan-5-ol. A simple preparative method for cis-stilbene is described.

Field evaluation of vaporised ethyl formate and carbon dioxide for fumigation of stored wheat

2009 ◽  
Vol 66 (4) ◽  
pp. 417-424 ◽  
Author(s):  
Greg Dojchinov ◽  
Katherine A Damcevski ◽  
James D Woodman ◽  
Victoria S Haritos
Keyword(s):  
Carbon Dioxide ◽  
Field Evaluation ◽  
Ethyl Formate ◽  
Stored Wheat

scholarly journals Synthesis, Characterization and Acute Anti-inflammatory Evaluation of New Mefenamic Acid Derivatives Having 4-Thiazolidinone Nucleus

2019 ◽  
Vol 28 (1) ◽  
pp. 138-146
Author(s):  
Mustafa H. Ali Alsafi ◽  
Muthanna S. Farhan
Keyword(s):  
Side Effects ◽  
Mefenamic Acid ◽  
Paw Edema ◽  
Compound I ◽  
Reference Drug ◽  
Cox 2 ◽  
Anti Inflammatory ◽  
Derivatives Of ◽  
Cox 1 ◽  
Inflammatory Effect

Mefenamic acid (MA) is one of the non-steroidal anti-inflammatory drugs, it is widely used probably due to having both anti-inflammatory and analgesic activity, the main side effects of mefenamic acid include gastrointestinal tract (GIT) disturbance mainly diarrhea, peptic ulceration, and gastric bleeding. The analgesic effects of NSAIDs are probably linked to COX-2 inhibition, while COX-1 inhibition is the major cause of this classic adverse effects. Introduction of thiazolidinone may lead to the increase in the bulkiness leads to the preferential inhibition of COX-2 rather than COX-1 enzyme. The study aimed to synthesize derivatives of mefenamic acid with more potency and to decrease the drug's potential side effects, new series of 4-thiazolidinone derivatives of mefenamic acid were synthesized IVa-g. The synthetic procedures for target compounds and their intermediates are designed to be as follows: acylation of secondary amine of mefenamic acid by chloroacetylchloride to produce compound (I), then reaction between compound (I) and hydrazine hydrate to form hydrazine derivative of mefenamic acid (compound II). After that, Schiff base formation by addition of seven benzaldehyde derivatives and finally, cyclization in presence of thioglycolic acid to form 4-thiazolidinone heterocyclic ring. The characterization of the titled compounds has been established on the basis of their spectral FTIR, 1HNMR data, and by measurements of their physical properties. In vivo acute anti-inflammatory effect of the synthesized compounds was evaluated in rats using egg-white induced edema model of inflammation. The tested compounds and the reference drug produced significant reduction of paw edema with respect to the effect of dimethyl sulfoxide 10%v/v (control group). Compound IVe showed more potent effect than mefenamic acid at 240-300 min, while at time 300 min, compounds IVa and IVd exhibit more potent anti-inflammatory effect than mefenamic acid (50mg/kg, i.p.) as they reduced paw edema significantly more than mefenamic acid at mentioned intervals (p<0.05) . On the other hand compound IVc exhibited lower anti-inflammatory effect.

Gas Chromatographic Analysis of Amino Acids as the jV-Heptafluorobutyryl Isobutyl Esters

1987 ◽  
Vol 70 (1) ◽  
pp. 151-160 ◽  
Author(s):  
Samuel L MacKenzie
Keyword(s):  
Amino Acids ◽  
Capillary Column ◽  
Packed Column ◽  
Complex Mixture ◽  
Amino Acid Profile ◽  
Reaction Sequence ◽  
Maximum Resolution ◽  
Acid Catalyzed ◽  
Derivatives Of ◽  
Heptafluorobutyric Anhydride

Abstract The N-heptafluoroburyryl isobutyl derivatives of proteic amino acids are well resolved by gas chromatography and form the basis of a convenient, rapid assay. The derivatives are prepared by acid-catalyzed esterification at 120°C for 20 min in 3N HCl-isobutanol followed by acylation with heptafluorobutyric anhydride at 150°C for 10 min. The reaction sequence is performed without any transfers or extractions and thus is compatible with microscale analysis. A complete proteic amino acid profile can be completed in less than 20 min by using a packed column or less than 10 min by using a capillary column in combination with an elevated oven temperature program rate. Physiological sample matrixes, which frequently contain a complex mixture of components, and thus require maximum resolution, can be assayed in less than 1 h using a program rate of 4°C/min. A capillary column is recommended for this application. Capillary column chromatography, in combination with a nitrogenspecific detector, is useful for identifying and assaying nonproteic amino acids in physiological sample matrixes. Frequently, a prior cleanup of the sample can be avoided.

Synthesis of Benzannulated Derivatives of Podocarpic Acid

1991 ◽  
Vol 44 (10) ◽  
pp. 1383 ◽  
Author(s):  
RC Cambie ◽  
MR Metzler ◽  
PS Rutledge ◽  
PD Woodgate
Keyword(s):  
Reaction Sequence ◽  
Derivatives Of ◽  
Moderate Yield

Two cyclopentaannulated derivatives of podocarpic acid have been converted into benzannulated derivatives by a two-step reaction sequence in moderate yield.

Distillable ionic liquids for a new multicomponent reaction

2007 ◽  
Vol 79 (11) ◽  
pp. 1869-1877 ◽  
Author(s):  
Anthony E. Rosamilia ◽  
Christopher R. Strauss ◽  
Janet L. Scott
Keyword(s):  
Carbon Dioxide ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Multicomponent Reaction ◽  
Reaction Medium ◽  
Building Blocks ◽  
Substituted Anilines ◽  
Reaction Sequence ◽  
Unsaturated Ketones ◽  
Direct Preparation

Adducts of dimethylamine and carbon dioxide form a "distillable ionic liquid" (DIMCARB) that may used as both a reaction medium and catalyst in the direct, atom-economical synthesis of useful synthetic building blocks, such as mono-condensed α,β-unsaturated ketones. The utilization of such building blocks in the synthesis of two new classes of versatile macrocycles, by a sequence of condensation reactions (H2O by-product), is described. Investigation into the mechanism of action of DIMCARB catalysis and observation of an aniline impurity arising from a competing reaction sequence led to development of a new multicomponent reaction for the direct preparation of 2- or 4-substituted anilines. Some of the macrocycles and anilines are, respectively, supramolecular host compounds and ligands for the preparation of metal complexes.

Synthesis and Evaluation of Novel Fluorobenzimidazole Derivatives as Antibacterial and Antifungal Agents

2019 ◽  
Vol 4 (4) ◽  
pp. 209-215
Author(s):  
D. Joshi ◽  
R. Narigara ◽  
G. Jani ◽  
K. Parikh
Keyword(s):  
Bacterial Strains ◽  
Compound I ◽  
Substituted Anilines ◽  
Gram Negative ◽  
E Coli ◽  
New Class ◽  
Antibacterial And Antifungal ◽  
Derivatives Of ◽  
Multiple Step

A new class of fluorobenzimidazole derivatives (IIIa-j)was synthesized to investigate their antimicrobial potential. All the compounds were prepared by multiple step synthesis, initiating from the synthesis of 5-(difluoromethoxy)-1H-benzimidazole-2-thiol (I). The compound I was further reacted with different derivatives of 2-chloro-N-phenylacetamide (IIa-j) prepared by reacting differently substituted anilines with chloroacetylchloride and triethylamine in DMF (solvent); resulting in formation of fluorobenzimidazoles IIIa-j. The compounds IIIa-j were characterized by spectral analysis viz. 1H NMR, 13C NMR, mass spectra, elemental analysis and IR. All these compounds were screened in vitro for their antimicrobial activity against Gram-positive (S. aureus and E. faecalis) and Gram-negative bacterial (E. coli and P.aeruginosa) strains as well as fungi (A. niger and C. albicans). Some of the compounds exhibited promising results (in MIC) against Gram-negative bacterial strains.

N-[2-(Pyridin-2-yl)ethyl]-derivatives of methane-, benzene- and toluenesulfonamide: prospective ligands for metal coordination

2013 ◽  
Vol 69 (11) ◽  
pp. 1397-1401 ◽  
Author(s):  
Danielle L. Jacobs ◽  
Benny C. Chan ◽  
Abby R. O'Connor
Keyword(s):  
Hydrogen Bonding ◽  
Dihedral Angles ◽  
Compound I ◽  
Torsion Angles ◽  
Methyl Group ◽  
A Value ◽  
Π Stacking ◽  
Linear Chains ◽  
Centroid Distance ◽  
Derivatives Of

The molecular and supramolecular structures are reported ofN-[2-(pyridin-2-yl)ethyl]methanesulfonamide, C8H12N2O2S, (I),N-[2-(pyridin-2-yl)ethyl]benzenesulfonamide, C13H14N2O2S, (II), andN-[2-(pyridin-2-yl)ethyl]toluenesulfonamide, C14H16N2O2S, (III). Although (II) and (III) are almost structurally identical, the N(amide)—C(ethyl)—C(ethyl)—C(pyridinyl) torsion angles for (I) and (II) are more closely comparable, with magnitudes of 175.37 (15)° for (I) and 169.04 (19)° for (II). This angle decreases dramatically with an additional methyl group in theparaposition of the sulfonamide substituent, resulting in a value of 62.9 (2)° for (III). In each of the three compounds there is an N—H...N hydrogen bond between the sulfonamide of one molecule and the pyridine N atom of a neighbor. Compound (I) forms hydrogen-bonded dimers, (II) uses its hydrogen bonding to connect supramolecular layers, and the hydrogen bonding of (III) connects linear chains to form layers. For arene-substituted (II) and (III), the different conformations afforded by the variable dihedral angles promote intermolecular π–π stacking in the benzene-substituted structure (II), but distorted intramolecular T-shaped π-stacking in the toluene-substituted structure (III), with a centroid-to-centroid distance of 4.9296 (10) Å.

Hydrogen bonding patterns in salts of derivatives of aminopyrimidine and thiobarbituric acid

2015 ◽  
Vol 71 (2) ◽  
pp. 144-152 ◽  
Author(s):  
Sundaramoorthy Gomathi ◽  
Jeyaraman Selvaraj Nirmalram ◽  
Packianathan Thomas Muthiah
Keyword(s):  
Hydrogen Bonds ◽  
Thiobarbituric Acid ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Compound I ◽  
Base Pairs ◽  
X Ray ◽  
Acid And Base ◽  
Derivatives Of ◽  
Primary Interaction

Three salts, namely 2-amino-4,6-dimethylpyrimidin-1-ium thiobarbiturate trihydrate (I), 2-amino-4,6-dimethoxypyrimidin-1-ium thiobarbiturate dihydrate (II) and 2,4-diamino-5-(3′,4′,5′-trimethoxybenzyl)pyrimidin-1-ium thiobarbiturate (III), were synthesized and characterized by IR and X-ray diffraction techniques. The primary interaction between the acid and base happensviaN—H...O hydrogen bonds in (II) and (III), andviawater-mediated N—H...OWand OW—HW...S in (I). The water molecules present in compound (I) form a (H2O)12water clusterviawater–water interactions. In all three compounds (I)–(III), thiobarbiturate anions form self-complementary pairs with a robustR22(8) motifviaa pair of N—H...O/N—H...S hydrogen bonds. They mimic the nucleobase base pairs by utilizing the same groups (thymine/uracil uses N3—H and C4=O8 groups during the formation of Watson–Crick and Hoogsteen base pairs with adenine). Compound (I) forms a water-mediated base pair through N—H...OWhydrogen bonds and forms anR42(12) motif. The formation of N—H...S hydrogen bonds, water-mediated base pairs and water–water interactions in these crystal systems offers scope for these systems to be considered as a model in the study of hydration of nucleobases and water-mediated nucleobase base pairs in macromolecules.

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