Mohamed Ramadan El Sayed Aly

Antiobesity, antioxidant and cytotoxicity activities of newly synthesized chalcone derivatives and their metal complexes.

Four sets of rationally designed chalcones were prepared for evaluation of their antiobesity, antioxidant and cytotoxicity activities. These sets include nine oleoyl chalcones as mimics of oleoyl estrone, three monohydroxy chalcones (chalcone ligands), Schiff base-derived chalcones and four copper as well as zinc complexes. Oleoyl chalcones 4d, 4e and particularly 6a as an isosteric isomer of oleoyl estrone, were as active as Orlistat on weight loss and related metabolic parameters using male SD rats in vivo. Chalcone ligands 10a-c and Schiff base-derived chalcones 11 and 14a,b were weakly antioxidants, while, the copper and zinc complexes 15a-d were good antioxidants with zinc chelates 15b,d being more active than their copper analogues 15a,cin vitro. Compounds 10c and 14a showed good cytotoxicity activities as Doxorubicin against PC3 cancer cell line in vitro, while, the copper complex 15c showed promising activity with IC₅₀ value of 5.95 μM. The estimated IC₅₀ value for Doxorubicin was 8.7 μM. Chalcones 14a,b are bifunctional probes for potential investigations in cancer diagnosis and radiotherapy by complexation with Gd(3+) or metal radioisotopes followed by posttranslation of Shiga toxin B-subunits that target globotriosyl ceramide expressing cancer cells.

Click reaction based synthesis, antimicrobial, and cytotoxic activities of new 1,2,3-triazoles ☆

Three-motif pharmacophoric models 20a-e and 21-25 were prepared in good yields by CuAAC of two azido substrates 2 and 11 with seven terminal acetylenic derivatives including chalcones 17a-e, theophylline 18 and cholesterol 19. The structure of these compounds was elucidated by NMR, MS, IR spectroscopy and micro analyses. This series was screened as antimicrobial and cytotoxic agents in vitro. Most derivatives showed appreciable antibacterial activity, but they displayed weak cytotoxic, and antifungal activities. Notably, conjugate 25 (cream of the crop) was found to be more active than Ampicillin against Escherichia coli and Staphylococcus aureus and showed appreciable antifungal and cytotoxic activities as well.

Synthesis of selenium-containing amino acid analogues and their biological study

Synthesis of selenium-containing amino acid analogues is described. These compounds were prepared in a concise and short synthetic route in good yields by nucleophilic substitution reaction of pyridineselenol and quinolineselenol derivatives with N-phthaloylglycyl chloride followed by hydrazinolysis. The newly synthesized compounds were screened against different strains of bacteria and fungi.

Recent Advances Toward Robust N-Protecting Groups for Glucosamine as Required for Glycosylation Strategies.

2-Amino-2-deoxy-d-glucose (d-glucosamine) is among the most abundant monosaccharides found in natural products. This constituent, recognized for its ubiquity, is presented in most instances as its N-acetyl derivative 2-acetamido-2-deoxy-d-glucopyranose (N-acetylglucosamine, GlcNAc, NAG). It occurs as the β-linked pyranosyl group in polysaccharides and oligosaccharides, and sometimes as the monosaccharide itself, either in its native state or as a glycoconjugate. The compounds acylation profile and other aspects of its structure are important elements in determining the variety of reactivities and functions of the molecule as a whole. Methods elaborated to investigate these challenges have been intensively reviewed; however, a relatively more comprehensive reviewing of this subject is introduced here to cover some aspects that have not been sufficiently covered. This might enable those who are beginners in this field to be aware of the subject in a more comprehensive context. 2-Amino-2-deoxy-d-glucosylation strategies demand robust amino-protecting groups that survive under a variety of chemical conditions, yet provide groups that can be deprotected under relatively mild conditions. At the end of this review, a table that includes all the N-protecting groups that have been used for glucosamine is provided to introduce them at a glance to aid in constructing building blocks that will act as useful 2-amino-2-deoxy-d-glucosyl donors.

Synthesis, insecticidal, and fungicidal screening of some new quinoline derivatives

This paper describes the synthesis of a series of quinolines graphted with hydrazones, pyrazoles, pyridazine, phthalazine, triazepinone, semicarbazide, and thiomorpholide moieties and four metal complexes. These derivatives were screened against Fusarium oxysporum and the red palm weevil (RPW) Rhynchophorus ferrugineus Oliver (coleopteran: Curculionidae) as palm pathogens. Only chlorinated quinolines were active against these organisms with hydrazones being good fungicides, while those modified with pyrazoles and pyrazines showed moderate insecticidal activity. A unique trihydroxylated hydrazone was active against both organisms, while another hydrazone, the most potent fungicide in this series, exhibited insecticidal activity only upon complexation with Zn2+ ions.

Synthesis of some quinolinyl chalcone analogues and investigation of their anticancer and synergistic anticancer effect with doxorubicin

Two derivatives of 2-(4-acetylanilino)quinolines (IIIa, b) were synthesized as scaffolds for synthesis of open chalcone analogues (Va-f) through Claisen-Schmidt condensation with a set of aromatic aldehydes (IVa-d). Derivatives (Va, b) were further manipulated into cyclic α,β-unsaturated ketones by Michael-addition of acetylacetone and ethylacetoacetate affording derivatives (VI–VII). Deethoxycarboxylation of derivatives (VIIa, b) afforded cyclohexenons (VIIIa, b) allowing formation of a mini library of α,β-unsaturated ketones for screening their anticancer and synergistic anticancer effect with doxorubicin using colon cancer cell line (Caco-2). Two open enones, (Vb) and (Ve), showed significant anticancer activity with IC50 of 5.0 and 2.5 μM respectively. Only one cyclic enone, (VIa) showed synergistic anticancer activity with doxorubicin at 10 μM.

Synthesis, antimicrobial and photoelectric potency of new ferrocene-based congeners

A set of quinoline, cholesterol, and monopyranoside tagged ferrocene-chalcone-1,2,3-triazole triads was prepared via simple CuAAC. Physico and photoelectric consideration of these conjugates disclosed the advantage of the quinoline derivative for UV photodetector applications rather than being a photosensitizer for photovoltaic cells. In vitro antimicrobial assaying revealed interesting antimicrobial potency of the ferrocene-monopyranosyl conjugates.Graphical abstract