Electron impact studies. LXXVIII. Rearrangement ions and proximity effects in the 'doubly charged ion' mass spectra of benzoic acid derivatives

1973 ◽  
Vol 26 (1) ◽  
pp. 195 ◽  
Author(s):  
JH Bowie
Keyword(s):  
Benzoic Acid ◽  
Mass Spectra ◽  
General Feature ◽  
Molecular Ions ◽  
Ring System ◽  
Proximity Effects ◽  
Carboxyl Groups ◽  
Benzoic Acids ◽  
Benzoic Acid Derivatives ◽  
Doubly Charged

The technique of Beynon1,2 has been used to determine the ?doubly charged ion? mass spectra of a series of benzoic acid derivatives. A general feature of all spectra is the presence of pronounced M-CO species. The losses of carbon monoxide from the doubly charged molecular ions of m- amino- and m-hydroxy-benzoic acids originate mainly from the carboxyl groups, whereas the predominant loss from benzoic acid involves the aryl ring system. The spectra of anthranilates and salicylates contain peaks produced by characteristic proximity effects.

scholarly journals Hydrogenation of benzoic acid derivatives over Pt/TiO2 under mild conditions

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Miao Guo ◽  
Xiangtao Kong ◽  
Chunzhi Li ◽  
Qihua Yang
Keyword(s):  
Electron Transfer ◽  
Benzoic Acid ◽  
High Efficiency ◽  
Carboxyl Groups ◽  
Carboxyl Group ◽  
Benzoic Acids ◽  
Catalyst Poisoning ◽  
Benzoic Acid Derivatives ◽  
Mild Conditions ◽  
Transfer Direction

AbstractHydrogenation of benzoic acid (BA) to cyclohexanecarboxylic acid (CCA) has important industrial and academic significance, however, the electron deficient aromatic ring and catalyst poisoning by carboxyl groups make BA hydrogenation a challenging transformation. Herein, we report that Pt/TiO2 is very effective for BA hydrogenation with, to our knowledge, a record TOF of 4490 h−1 at 80 °C and 50 bar H2, one order higher than previously reported results. Pt/TiO2 catalysts with electron-deficient and electron-enriched Pt sites are obtained by modifying the electron transfer direction between Pt and TiO2. Electron-deficient Pt sites interact with BA more strongly than electron-rich Pt sites, helping the dissociated H of the carboxyl group to participate in BA hydrogenation, thus enhancing its activity. The wide substrate scope, including bi- and tri-benzoic acids, further demonstrates the high efficiency of Pt/TiO2 for hydrogenation of BA derivatives.

Mass spectral studies of some desaurins and related 3,5-bismethylene-1,2,4-trithiolanes

1968 ◽  
Vol 46 (3) ◽  
pp. 365-375 ◽  
Author(s):  
Peter Yates ◽  
Thomas R. Lynch ◽  
L. S. Weiler
Keyword(s):  
Carbonyl Group ◽  
Mass Spectra ◽  
Molecular Ions ◽  
Spectral Studies ◽  
Mass Measurements ◽  
Metastable Peak ◽  
Fragmentation Pathways ◽  
Mass Spectral ◽  
Accurate Mass Measurements ◽  
Doubly Charged

The mass spectra of three desaurins and four related 3,5-bismethylene-1,2,4-trithiolanes have been interpreted with the aid of metastable peak assignments and accurate mass measurements. Strong molecular ion peaks are observed in the case of the aryl desaurins but not in that of their trithiolane counterparts. A variety of fragmentation pathways are postulated for the molecular ions, including cleavage on either side of a carbonyl group and elimination of a molecule of acylthioketene. In the case of the desaurins the latter process results in the formation of acylthioketene molecular ions, which could be distinguished from the doubly charged desaurin molecular ions. In the case of two of the trithiolanes, it is proposed that the ions resulting from loss of acylthioketene from the molecular ions undergo a novel type of McLafferty rearrangement and loss of carbon suboxysulfide to give aryl mercaptan molecular ions.

Benzo[c]cinnoline derivatives. IV. Substituent effects in the mass spectra of substituted Benzo[c]cinnolines

1968 ◽  
Vol 21 (5) ◽  
pp. 1233 ◽  
Author(s):  
JH Bowie ◽  
GE Lewis ◽  
JA Reiss
Keyword(s):  
Mass Spectra ◽  
Substituent Effects ◽  
Molecular Ions ◽  
Proximity Effects ◽  
Skeletal Rearrangement ◽  
Fragmentation Processes

The mass spectra of a series of benzo[c]cinnoline derivatives are reported and discussed. The spectra are useful for analytical purposes, as all compounds give pronounced molecular ions, and the fragmentation processes generally occur without skeletal-rearrangement. Many benzo[c]cinnolines which are substituted in the 4-position may be differentiated from other isomers by the presence of "proximity- effects" in their mass spectra.

Oxygen equilibration in the mass spectra of 2-benzoylbenzoic acid

1976 ◽  
Vol 29 (2) ◽  
pp. 301
Author(s):  
MJ Lacey ◽  
JS Shannon
Keyword(s):  
Mass Spectrum ◽  
Benzoic Acid ◽  
Electron Impact ◽  
Mass Spectra ◽  
Chemical Ionization ◽  
Molecular Ions ◽  
Electron Impact Mass Spectrum ◽  
Primary Fragmentation ◽  
Electron Impact Mass ◽  
Impact Mass

Positional integrity of the label is maintained in the molecular ions of 2-ben~oyl[18O]benzoic acid prior to a number of primary fragmentation modes. Positional integrity is also evident for some source and metastable reactions of the protonated molecular ions formed in its chemical ionization (H2) mass spectrum. The (M-Ph)+ ions formed in the electron impact mass spectrum, however, fragment further after complete equilibration of their oxygen atoms.

scholarly journals CYP199A4 catalyses the efficient demethylation and demethenylation of para-substituted benzoic acid derivatives

RSC Advances ◽  
2015 ◽  
Vol 5 (64) ◽  
pp. 52007-52018 ◽  
Author(s):  
Tom Coleman ◽  
Rebecca R. Chao ◽  
John B. Bruning ◽  
James J. De Voss ◽  
Stephen G. Bell
Keyword(s):  
Cytochrome P450 ◽  
Benzoic Acid ◽  
Rhodopseudomonas Palustris ◽  
Cytochrome P450 Enzyme ◽  
Benzoic Acids ◽  
Benzoic Acid Derivatives ◽  
P450 Enzyme

CYP199A4, a cytochrome P450 enzyme from Rhodopseudomonas palustris HaA2, is able to efficiently demethylate a range of benzoic acids at the para-position. It can also catalyse demethenylation reactions.

scholarly journals Assessment of the toxicity of benzoic acid derivatives in the intragastric intake

2020 ◽  
Vol 99 (7) ◽  
pp. 755-760
Author(s):  
Larisa G. Gorokhova ◽  
Nadezhda N. Mikhailova ◽  
Evgeniya V. Ulanova ◽  
Tatyana K. Yadykina
Keyword(s):  
Benzoic Acid ◽  
The Body ◽  
Morphological Data ◽  
Benzoic Acids ◽  
Chemical Production ◽  
Hazard Class ◽  
Chlorobenzoic Acid ◽  
Benzoic Acid Derivatives ◽  
Derivatives Of ◽  
Predominant Effect

Introduction. Benzoic acid and its numerous derivatives are widely used in all areas of chemical production. However, there is no information about the toxic properties of a large number of benzoic acid derivatives. The purpose of the study was to study the toxic properties of several derivatives of benzoic acids in intragastric intake in an experiment.Material and methods. The following derivatives of benzoic acid were studied: 4-chlorobenzoic, 4-methoxybenzoic, p-acetoxybenzoic and 2-methoxy-5-sulfamoylbenzoic acids. The studies were performed on white laboratory rats; toxicity was studied in repeated experiments with the oral administration of substances. The condition of the animals was assessed by integrated parameters, indices of biochemical analyzes of blood serum, morphological data from a study of the liver, kidneys, heart, stomach, pancreas and thyroid glands.\Results. According to toxicometric data, 4-chlorobenzoic acid is classified as moderately hazardous, hazard class III, 4-methoxybenzoic, p-acetoxybenzoic and 2-methoxy-5-sulfamoylbenzoic acids belong to hazard class IV (low hazard). Under the subchronic administration of all the studied compounds, there was a significant increase in urea concentration, aminotransferase activity, and a decrease in catalase activity, most pronounced in poisoning with 4-chlorobenzoic and 4-methoxybenzoic acids. Morphohistological studies confirmed the predominant effect of benzoic acid derivatives on the functioning of the hepatorenal system in the animals exposed to poisoning. Microscopically fatty liver dystrophy was observed, there was a diffuse proliferation of Kupffer cells. In the kidneys, the glomeruli were enlarged in size; the lumen of the Shumlyansky-Bowman’s capsule was narrowed as a result of swelling of the capillary endothelium.Conclusion. Subchronic oral intake of 4-chlorobenzoic, 4-methoxybenzoic, p-acetoxybenzoic, and 2-methoxy-5-sulfamoylbenzoic acids leads to many disorders in the body, which are mainly of a common toxic nature with a predominant effect on the state of the hepatorenal system. The most pronounced organotoxic effect is manifested in the chlorine-containing derivative of benzoic acid - 4-chlorobenzoic acid. Due to the low toxicity of benzoic acids, chronic poisoning in the workplace is unlikely; it is possible only if the technological processes are disrupted.

Bjerkandera adusta as a source of benzoic acid derivatives targeting 26S proteasome and cathepsins B&L

2019 ◽  
Author(s):  
K Georgousaki ◽  
N Tsafantakis ◽  
S Gumeni ◽  
V González-Menéndez ◽  
G Lambrinidis ◽  
...  
Keyword(s):  
Benzoic Acid ◽  
26S Proteasome ◽  
Bjerkandera Adusta ◽  
Benzoic Acid Derivatives

2,4-Dichloro-5-[(N-aryl/alkyl)sulfamoyl]benzoic Acid Derivatives: In Vitro Antidiabetic Activity, Molecular Modeling and In silico ADMET Screening

2019 ◽  
Vol 15 (2) ◽  
pp. 186-195 ◽  
Author(s):  
Samridhi Thakral ◽  
Vikramjeet Singh
Keyword(s):  
Molecular Docking ◽  
Benzoic Acid ◽  
Inhibitory Activity ◽  
In Silico ◽  
Computational Study ◽  
Antidiabetic Activity ◽  
Standard Drug ◽  
Benzoic Acid Derivatives ◽  
In Silico Admet ◽  
Inhibitory Potential

Background: Postprandial hyperglycemia can be reduced by inhibiting major carbohydrate hydrolyzing enzymes, such as α-glucosidase and α-amylase which is an effective approach in both preventing and treating diabetes. Objective: The aim of this study was to synthesize a series of 2,4-dichloro-5-[(N-aryl/alkyl)sulfamoyl] benzoic acid derivatives and evaluate α-glucosidase and α-amylase inhibitory activity along with molecular docking and in silico ADMET property analysis. Method: Chlorosulfonation of 2,4-dichloro benzoic acid followed by reaction with corresponding anilines/amines yielded 2,4-dichloro-5-[(N-aryl/alkyl)sulfamoyl]benzoic acid derivatives. For evaluating their antidiabetic potential α-glucosidase and α-amylase inhibitory assays were carried out. In silico molecular docking studies of these compounds were performed with respect to these enzymes and a computational study was also carried out to predict the drug-likeness and ADMET properties of the title compounds. Results: Compound 3c (2,4-dichloro-5-[(2-nitrophenyl)sulfamoyl]benzoic acid) was found to be highly active having 3 fold inhibitory potential against α-amylase and 5 times inhibitory activity against α-glucosidase in comparison to standard drug acarbose. Conclusion: Most of the synthesized compounds were highly potent or equipotent to standard drug acarbose for inhibitory potential against α-glucosidase and α-amylase enzyme and hence this may indicate their antidiabetic activity. The docking study revealed that these compounds interact with active site of enzyme through hydrogen bonding and different pi interactions.

Investigation of 2-Fluoro Benzoic Acid Derivatives as Influenza A Viral Sialidase Selective Inhibitors

2010 ◽  
Vol 9 (4) ◽  
pp. 198-204 ◽  
Author(s):  
Sadagopan Magesh ◽  
Nongluk Sriwilaijaroen ◽  
Vats Savita ◽  
Hiromune Ando ◽  
Taeko Miyagi ◽  
...  
Keyword(s):  
Benzoic Acid ◽  
Influenza A ◽  
Selective Inhibitors ◽  
Benzoic Acid Derivatives

Inductive effect in EI-mass spectra of some 5,6-dihalogenides and 5,6-halohydrins of 5α-cholestan-3β-ol and 3β-acetoxy-5α-cholestane

1982 ◽  
Vol 47 (11) ◽  
pp. 2946-2960 ◽  
Author(s):  
Antonín Trka ◽  
Alexander Kasal
Keyword(s):  
Mass Spectra ◽  
Inductive Effect ◽  
Molecular Ions ◽  
Hydroxyl Group ◽  
Halogen Atoms ◽  
Derivatives Of

Partial EI-mass spectra of 3β-hydroxy- and 3β-acetoxy-5α-cholestanes substituted in positions 5α-, 6β- or 5α,6β- with a hydroxyl group or halogen atoms (fluorine, chlorine, bromine) are presented. The molecular ions of 5α,6β-disubstituted derivatives of 3β-hydroxy-5α-cholestane (or of its 3-acetate) are considerably more stable than the corresponding monosubstituted derivatives if at least one of the pair of the vicinal substituents is chlorine or fluorine. This increase in stability, most striking in 5α- and 6β-fluoro compounds, is explained by the inductive effect.

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