Publications by authors named "Ahmed Bakr Abdelwahab"

4 Publications

  • Page 1 of 1

Synthetic Routes to Coumarin(Benzopyrone)-Fused Five-Membered Aromatic Heterocycles Built on the α-Pyrone Moiety. Part II: Five-Membered Aromatic Rings with Multi Heteroatoms.

Molecules 2021 Jun 4;26(11). Epub 2021 Jun 4.

Laboratoire Lorrain de Chimie Moléculaire (L.2.C.M.), Université de Lorraine, 57078 Metz, France.

Coumarins are natural heterocycles that widely contribute to the design of various biologically active compounds. Fusing different aromatic heterocycles with coumarin at its 3,4-position is one of the interesting approaches to generating novel molecules with various biological activities. During our continuing interest in assembling information about fused five-membered aromatic heterocycles, and after having presented mono-hetero-atomic five-membered aromatic heterocycles in Part I. The current review Part II is intended to present an overview of the different synthetic routes to coumarin (benzopyrone)-fused five-membered aromatic heterocycles with multi-heteroatoms built on the pyrone ring, covering the literature from 1945 to 2021.
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http://dx.doi.org/10.3390/molecules26113409DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8200119PMC
June 2021

Synthetic Routes to Coumarin(Benzopyrone)-Fused Five-Membered Aromatic Heterocycles Built on the α-Pyrone Moiety. Part 1: Five-Membered Aromatic Rings with One Heteroatom.

Molecules 2021 Jan 18;26(2). Epub 2021 Jan 18.

Laboratoire Lorrain de Chimie Moléculaire (L.2.C.M.), Université de Lorraine, 57050 Metz, France.

This review gives an up-to-date overview of the different ways (routes) to the synthesis of coumarin (benzopyrone)-fused, five-membered aromatic heterocycles with one heteroatom, built on the pyrone moiety. Covering 1966 to 2020.
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http://dx.doi.org/10.3390/molecules26020483DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7831143PMC
January 2021

New approach in the characterization of bioactive compounds isolated from Calycotome spinosa (L.) Link leaves by the use of negative electrospray ionization LITMS, LC-ESI-MS/MS, as well as NMR analysis.

Bioorg Chem 2020 03 23;96:103535. Epub 2019 Dec 23.

Laboratoire de Mycologie, de Biotechnologie et de l'Activité Microbienne (LaMyBAM), Département de Biologie Appliquée, Université des Frères Mentouri, Constantine1, BP, 325 Route de Aïn El Bey, Constantine 25017, Algeria.

Two novel compounds were isolated for the first time from Calycotome spinosa (L.) Link, an alkaloid 5-Hydroxy-1H-indole (4) and a cyclitol D-pinitol (5), together with the three well-known flavonoids; Chrysin-7-O-(β-D-glucopyranoside) (1), Chrysin-7-O-β-D-(6″-acetyl)glycopyranoside (2) and Apigenin-7-O-β-D-glycopyranoside (3). The chemical structures of the isolated compounds were elucidated by spectroscopic data and mass spectrometric analyses; including a fresh approach 1D-NMR, 2D-NMR with LC-ESI-MS/MS. In this study, the new compound (4) that has been obtained from the leaves MeOH extract presented the best radical scavenging activity (DPPH) (IC < 10 µg/mL) compared to the standard butylated hydroxytoluene (BHT, IC = 34.73 ± 0.23 μg/mL) and showed the highest total antioxidant capacity (TAC = 985.54 ± 0.13 mg AAE/g extract) in contrast to ascorbic acid (TAC = 905.95 ± 0.07 mg AAE/g extract). Furthermore, the strongest reducing power (EC = 344.82 ± 0.02 µg/mL), as well as the remarkable scavenging potential by ABTS assay (IC = 7.8 ± 0.43 µg/mL), were exhibited by the same composite (4). Followed by the methanol crude extract and the compound (3) that also showed a potent antioxidant (DPPH; IC = 41.04 ± 0.15 and 47.36 ± 0.21 µg/mL, TAC; 671.02 ± 0.21 and 608.67 ± 0.34 mg AAE/g extract, FRAP; EC = 763.73 ± 0.32 and 814.61 ± 0.31 µg/mL, ABTS; IC = 19.18 ± 0.06 and 63.72 ± 0.64 µg/mL, respectively), but less than the previous samples. On the opposite side, compound (5) had the lowest activity, in which its values were less interesting to determine. Moreover, compound (4) has equally exerted an attractive antibacterial activity against Staphylococcus aureus (ATTC-25923), Pseudomonas aeruginosa (ATTC- 27853) and Salmonella abony (NCTC 6017), as measured by the disc diffusion assay, with inhibition zones of 16 ± 0.5, 9.83 ± 0.29 and 8 ± 0.28 mm, in that order. To the best of our knowledge, 5-Hydroxy-1H-indole was isolated from plants for the second time in our current work. Thus, the obtained results from this investigation propose that the leaves of C. spinosa are a rich natural source for value molecules as potential antioxidants and antimicrobial agents for best human health.
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http://dx.doi.org/10.1016/j.bioorg.2019.103535DOI Listing
March 2020

Natural and Synthetic Coumarins with Effects on Inflammation.

Molecules 2016 Oct 2;21(10). Epub 2016 Oct 2.

SRSMC, UMR 7565, Groupe HeCRIN, ICPM, 1 boulevard Arago, 57070 Metz, France.

In this review, we will present the different aspects of coumarins and derivatives, from natural origins or synthetically prepared, and their action on inflammation. Coumarins and also furo- and pyranocoumarins are found in many different plants. These compounds are very often investigated for antioxidant properties. Other biological properties are also possible and anti-inflammation activity is one of these. As coumarins are also available quite easily via synthesis, natural ones can be prepared this way but derivatives with special substituents are also feasible. A review on the same topic appeared in 2004 and our contribution will take into account everything published since then.
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http://dx.doi.org/10.3390/molecules21101322DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6273422PMC
October 2016
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