substitution product
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Foods ◽  
2022 ◽  
Vol 11 (1) ◽  
pp. 119
Author(s):  
Ebtihal Yaqoob Khojah ◽  
Ahmed Noah Badr ◽  
Dalia Amin Mohamed ◽  
Adel Gabr Abdel-Razek

Food is the source from where a person obtains the body’s daily requirements. People’s current daily habits force them to consume fast food, which is known for its poor nutritional and safety features. So, it is urgent to provide a suitable substitution product to solve this issue. The present investigation aimed to produce a bar with a dual function: nutritional and long shelf life. Two materials were chosen to support the bar manufacturing regarding their bioactive contents, barley malt grass (BMG) and pomegranate byproducts (PBD). Chemical composition, antioxidant, and antimicrobial potency were measured. Β-carotene, vitamin C, and tocopherol were determined using HPLC apparatus. Extracts’ bio-safety against cell lines was determined, besides their enhancement against cell-death factors. Simulation experiments were designed to evaluate extracts’ impact to extend bar shelf life. Data represented the richness of essential minerals and fibers. Results of the FTIR reflected the existence of various active groups in the contents. Phenolic fractions of PBD are distinctive for their content of ellagic (39.21 ± 5.42 mg/kg), ferulic acid fractions (31.28 ± 4.07 mg/kg) which is a known with antifungal activity. Extracts and their mix (1:1) represented inhibition zone diameters that reach 15.1 ± 1.66 mm for bacteria and 23.81 ± 1.41 mm for fungi. Extracts were shown to have better safety against the cell line strain of hepatic HL-7702, with an elevation of a harmful dose of aflatoxin (IC50 304.5 µg/mL for PBD, IC50 381 µg/mL for BMG). Sensory evaluation of fortified bars reflected a preferable application of mix (1:1) due to color attributes and panelist evaluations, the same result recorded for simulation studies. The experiment recommended applying a mix (1:1) of BMG: PBD in addition to their extracts (200 mg/kg dough) for functional bar manufacturing with antifungal properties.


2021 ◽  
pp. 15-25
Author(s):  
E.M. Yergaliyeva ◽  
◽  
L.A. Kayukova ◽  
A.V. Vologzhanina ◽  
G.P. Baitursynova ◽  
...  

Amidoxime derivatives have practically valuable biological properties. We have previously obtained new spiropyrazolinium compounds by arylsulfo-chlorination of β-aminopropioamidoximes, but in case of β-(benzimidazol-1-yl)pro-pioamidoxime we have obtained O-substitution product – 3-(1H-benzo[d]imidazol-1-yl)-N'-(tosyloxy)pro-panimidamide. The aim of the work is predicting of structural parameters (bond lengths, bond angles), vibrational frequencies and NMR spectra of 3-(1H-benzo-[d]imidazol-1-yl)-N'-(tosyloxy)propanimidamide. The calculations were performed using Gaussian 09 package. Structural parameters and vibrational frequencies was calculated using DFT (B3LYP/B3PW91/WB97XD)/6-31G(d,p). 1H and 13C NMR was predicted using DFT B3LYP/6-31G(d,p)-GIAO in DMSO. All calculated values are in good agreement with experimental data. The calculated bond lengths and bond angles were compared with results of X-ray structural analysis. The best correlation coefficient was 0.981 (calcu-lations with B3LYP level). For bond angles, the best result was obtained with B3LYP level (0.990). For vibrational frequencies correlation coefficients between the calculated and experimental values were 0.997 (B3LYP), 0.996 (B3PW91) and 0.995 (WB97XD). The most accurate method was used for predic-ting NMR spectrum. The correlation coefficients between the experimental and calculated 1H and 13C chemical shifts were 0.949 and 0.999 respectively.


Author(s):  
Farhana Yasmin ◽  
Md. R. Amin ◽  
Anowar Hosen ◽  
M.A. Kawsar Sarkar

The widening importance of carbohydrate derivatives as unrivaled potential antimicrobial and therapeutic drugs has attracted attentionto the synthesis of mannopyranoside derivatives. In the present study, regioselective 3-bromobenzoylation of methyl α-D-mannopyranoside (1) was carried out using the direct method and gave the corresponding 6-O-(3-bromobenzoyl) derivative (2) in excellent yield. A number of 2,3,4-tri-O-acyl derivatives (3–10) of this 6-substitution product using a wide variety of acylating agents were also prepared in order to obtain newer derivatives of synthetic and biological importance. The chemical structures of the newly synthesized compounds were ascertained by analyzing their physicochemical, elemental, and spectroscopic data. Additionally, the X-ray powder diffraction (XRD) of these acylated products was studiedfor quantitatively identifying crystalline compounds.Therefore, due to the importance of carbohydrates, it might be useful to develop a good method for the synthesis of carbohydrate-based drugs of the current global situation for health and disease


2021 ◽  
Vol 13 (2) ◽  
pp. 657-668
Author(s):  
S. A. Chowdhury ◽  
S. C. Bhattacharjee

Over the past several decades significant biological activities including brains protective and antimicrobial activities have made sugar esters (SEs) as a topic of great interest. In this context, unimolar 3-chlorobenzoylation of methyl α-L-rhamnopyranoside (4) using dibutyltin oxide method regioselectively furnished only the 3-O-substitution product 5 in excellent yield. The reaction proceeded via the formation of a cyclic 2,3-O-dibutylstannylene intermediate where equatorial hydroxyl group is activated by the tin atom leading to the formation of product 5 only. To get biologically important rhamnopyranoside esters chlorobenzoate 5 was further converted into three newer 2,4-di-O-acyl products 6-9 with other acylating agents using direct acylation method. Prediction of activity spectra for substances (PASS) indicated that these rhamnopyranoside esters have many promising biological profiles including CYP2H substrate, membrane permeability inhibitor and better antifungal activities. Additionally, ADMET and drug likeness properties of SEs 5-8 were predicted and discussed.


Foods ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 925
Author(s):  
Johannes Pitsch ◽  
Otmar Höglinger ◽  
Julian Weghuber

Acrylamide is assumed to be a potential carcinogen, and reference values have therefore been implemented in EU legislation. Thus, the food industry needs to reduce the acrylamide content in consumer products to the lowest possible value. In this study, roasted rye was evaluated for its suitability as a coffee substitution product with respect to its acrylamide content. The influence of process modifiers, free asparagine content, storage, and rye type on the final content of acrylamide was investigated. Changes in carbohydrate composition and brightness caused by the roasting process were described. Sample analysis was conducted via GC-MS and HPLC-CAD. Existing methods were adapted to roasted rye as the sample matrix. CaCl2 and asparaginase treatment as well as pH adjustments prior to roasting did not prove to reduce the acrylamide content. A significantly (* p < 0.027) lower free asparagine content in the raw material resulted in a lower formation of acrylamide in the final product. The acrylamide content significantly decreased (**** p < 0.0001) after 3 (1100 ± 18 µg kg−1) and 6 (490 ± 7 µg kg−1) months of long-term storage. Only samples stored for 6 months (490 ± 7 µg kg−1) met the EU acrylamide content requirements (<500 µg kg−1) for grain-based coffee substitution products.


Author(s):  
Elena Chirkina ◽  
Leonid Krivdin ◽  
Nikolay Korchevin

The theoretical mechanism of the interaction of 1,3-dichloropropene with 1,2- ethanedithiol in the system "hydrazine hydrate-KOH" has been proposed by the method of B3LYP / 6- 311 ++ G (d, p) in the framework of the theory of the electron-density functional according to which the reaction proceeds successively in several stages, including the nucleophilic substitution of the chlorine atom present in the sp3-hybridized carbon atom with a sulfur atom to form a mono-substitution product that undergoes a prototropic allylic rearrangement that migrates the double bond to the sulfur atom, followed by closure in the dithiolane cycle due to the nucleophilic attack of the sulfide anion of the second thiol group of the reagent per carbon atom located in the γ-position with respect to the second chlorine atom.


Author(s):  
Elena Chirkina ◽  
Leonid Krivdin ◽  
Nikolay Korchevin

The theoretical mechanism of the interaction of 1,3-dichloropropene with 1,2-ethanedithiol in the system "hydrazine hydrate-KOH" has been proposed by the method of B3LYP / 6-311 ++ G (d, p) in the framework of the theory of the electron-density functional according to which the reaction proceeds successively in several stages, including the nucleophilic substitution of the chlorine atom present in the sp3-hybridized carbon atom with a sulfur atom to form a mono-substitution product that undergoes a prototropic allylic rearrangement that migrates the double bond to the sulfur atom, followed by closure in the dithiolane cycle due to the nucleophilic attack of the sulfide anion of the second thiol group of the reagent per carbon atom located in the γ-position with respect to the second chlorine atom.


2018 ◽  
Vol 1 (12) ◽  
pp. 114-120
Author(s):  
Elena Chirkina

According to the results of quantum chemical studies in the framework of the electron density functional theory, the B3LYP / 6-311 ++ G (d, p) method proposed a theoretical mechanism for the interaction of 1,3-dichloropropene with 1,2-ethanedithiol in the hydrazine-hydrateKOH system. It was shown that the reaction proceeds sequentially in several stages, including the nucleophilic substitution of the chlorine atom of the sp3 hybridized carbon atom to the sulfur atom with the formation of the mono-substitution product, which undergoes prototropic allyl rearrangement, providing the double bond to the atom sulfur. Next, the dithiolan ring closes due to the nucleophilic attack of the sulfide anion of the second thiol group of the reagent on the carbon atom, which is in the γ position relative to the second chlorine atom. The resulting vinyldithiolan is isomerized to a more stable ethylidene-dithiolan as a result of prototropic allyl rearrangement


2018 ◽  
Vol 15 (5) ◽  
pp. 707-714 ◽  
Author(s):  
Konstantin V. Shcherbakov ◽  
Yanina V. Burgart ◽  
Victor I. Saloutin ◽  
Oleg N. Chupakhin

Aim and Objective: The objective of our work was to study the peculiarities of transformations of fluorine-containing flavone-3-carboxylates with N-nucleophiles, including biogenic amines and amino acids. Materials and Methods: 6,7,8-Trifluoro and 5,6,7,8-tetrafluoroflavone-3-carboxylates were involved in interactions with a number of N-nucleophiles, such as pyrrolidine, morpholine, proline, arginine, gammaaminobutyric acid, beta-alanine, histamine, dopamine and amantadine under different reaction conditions. All synthesized compounds were characterized by NMR 1H, 19F, (NMR 13C for some compounds) and IR spectroscopic data, and elemental analysis. Results: 3-(Ethoxycarbonyl)polyfluoroflavones react with morpholine, pyrrolidine and L-proline to form 7- monosubstituted flavone-3-carboxylates. For the reactions of tetrafluoroflavone with pyrrolidine and morpholine, the formation of 5,7-disubstituted products is also possible. Interaction with gamma-aminobutyric acid leads to the 4-{[3-ethoxy-2-(2-hydroxypolyfluorobenzoyl)-3-oxo-1-phenylprop-1-enyl]amino}butanoic acids as a result of the pyrone ring opening. In reactions with dopamine, histamine, L-arginine and β-alanine, polyfluoroflavone-3-carboxylates underwent a chromone-coumarin rearrangement. 3-(Ethoxycarbonyl)tetrafluoroflavone forms with amantadine the nucleophilic aromatic substitution product, while trifluoro-substituted analog gives the chromone-coumarin rearrangement product. Conclusion: This work showed possibilities of chemical modification of polyfluorinated flavones in the reactions with amines depending on the structure of the nucleophilic reagent. Synthesized compounds are of interest for biological testing.


Author(s):  
Zane Clarke ◽  
Evan Barnes ◽  
Kate L. Prichard ◽  
Laura J. Mares ◽  
Jack K. Clegg ◽  
...  

The effect of different leaving groups on the substitutionversuselimination outcomes with C-5 D-glucose derivatives was investigated. The stereochemical configurations of 3-O-benzyl-1,2-O-isopropylidene-5-O-methanesulfonyl-6-O-triphenylmethyl-α-D-glucofuranose, C36H38O8S (3) [systematic name: 1-[(3aR,5R,6S,6aR)-6-benzyloxy-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxol-5-yl)-2-(trityloxy)ethyl methanesulfonate], a stable intermediate, and 5-azido-3-O-benzyl-5-deoxy-1,2-O-isopropylidene-6-O-triphenylmethyl-β-L-idofuranose, C35H35N3O5(4) [systematic name: (3aR,5S,6S,6aR)-5-[1-azido-2-(trityloxy)ethyl]-6-benzyloxy-2,2-dimethyltetrahydrofuro[2,3-d][1,3]dioxole], a substitution product, were examined and the inversion of configuration for the azido group on C-5 in4was confirmed. The absolute structures of the molecules in the crystals of both compounds were confirmed by resonant scattering. In the crystal of3, neighbouring molecules are linked by C—H...O hydrogen bonds, forming chains along theb-axis direction. The chains are linked by C—H...π interactions, forming layers parallel to theabplane. In the crystal of4, molecules are also linked by C—H...O hydrogen bonds, forming this time helices along thea-axis direction. The helices are linked by a number of C—H...π interactions, forming a supramolecular framework.


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