Search

Novel chitosan nanoparticles (SCN) were synthesized via reaction of chitosan with different concentration of 2-chloro-N-(3-methylisoxazol-5-yl) acetamide (5 %, 10 % and 15 %) at 70–80 °C for 7 h to give the grafted polymer, which condensed with cyclohexanone Mannich base 45 °C for 7 h to afford the corresponding (SCN). These were stirred with Deflazacort drug to achieve the Deflazacort loading (SCN), which, compressed with calcium starch glycolate (CaSgly) to give the corresponding tablets. The pH 2. 1 and concentration of SCN-10 %/CaSgly (1:4) was found to be important parameters in controlling the release profiles.

The following review article provides an overview of DHA chemistry, with specific confirmation based on major historical developments and progress mainly made over the last two decenniums. It is our hope this review serves as a valuable treasure to those interested in the 3-acetyl-4-hydroxy-6-methyl-2H-pyran-2-one (DHA) chemistry, and helps impact future advancements.

This review supply an inclusive survey of the recent progress in the chemistry of 4,6‐dimethyl-3-amino-3H-pyrazolo[3,4-b]pyridine concerning the synthesis and reactions and biological activity over...

Thesis Abstract: Coumarin compounds are one of the most active classes of heterocyclic compounds. They play active roles in medicine due to their biological activity. These compounds are found in many natural products. Hydroxylochocarpin (a), lonchocarpin (b) and lonchocarpene (c) are used as anticancer reagents. Moracin D (d) used as an antifungal while cromakalim (e) produces anti-hypertensive effects and SD-8381(f) produces anti-inflammatory effects as a new cyclooxygenase inhibitor. Catechin (g) and epigallocatechin gallate [EGCG] (h) both represent antiallergic and anticancer effects, while KRH-102140 (i) is identified as a5-lipoxygenase (5-LO) inhibitor. Seseline (j) and xanthylein (k) exhibit anticancer activities. Rotenone (l) used as an anti-anaphylactic agent for treating asthma. Also dronabinol [∆9-THC] (m) and other cannabinoids used for treating symptoms of cancer. Suksdorfin (n) inhibits the human immunodeficiency virus (HIV) while daleformis (o) inhibits the endothelin-converting enzyme. The aim of the present work is to design and synthesize fused bicyclic and polycyclic ring systems via enamino derivatives incorporating benzopyrone moiety (coumarin structure).

Heterocyclic compounds containing nitrogen, oxygen and sulfur atoms possess various interesting biological activities. Among these compounds, 1,3-oxathiolan-5-one and its diverse derivatives which are literature documented ones of the most potent core structures in drug design and pharmaceutical industry. This thesis describes the utility of 1,3-oxathiolan-5-one in the synthesis of pyridinonethiol and their annulated systems through multicomponent reaction of 2-methyl-2-phenyl-1,3-oxathiolan-5-one (1), aniline and α,β-unsaturated carbonyl compounds. On the other hand, different bioactive heterocyclic systems such as thiophene, furo-oxathiolone, mercapto-diphenylcyclopenta-2,4-dien-one, triazole and thiadiazine have been efficiently synthesized via tandem reactions of 1,3-oxathiolan-5-one 1 with different nucleophilic reagents. The structures of newly synthesized compounds were confirmed by spectral data, elemental analyses and mechanically discussed. Also, in vitro antioxidant and antitumor activities of these compounds were evaluated. In addition, the synthesized compounds were screened against hepatic cancer cell line HepG-2, as the optimistic results exhibited that compounds 29, 33 and 34 have excellent antioxidant and anti HepG-2 activities.

This review highlights the recently cited research data in the literature on the chemistry of 2-chloroquinoline-3-carbaldehyde and related analogs and their applications over the period from 2013 to 2017. It covers: synthesis of quinoline ring systems and reactions adopted to construct fused or binary quinoline-cord heterocyclic systems. The biological evaluation and the synthetic applications of the target compounds were illustrated.

A new series of 5-arylazo-3-cyano-2-pyridone scaffolds 5, 6 and 7 have been synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopic tools. The antibacterial activities of the synthesized pyridone scaffolds have been investigated; they exhibited good activities compared to the standard drugs.

Thiazolidin-4-one derivative 3 was synthesized by the transformation of chloroacetamide derivative 2 with NH4SCN.The condensation of 3 with p-anisaldehyde afforded the corresponding arylidene derivative 4. Also, the alkylation of chloroacetamide derivative 2 with different heterocyclic compounds was investigated. Annulation of 5-amino-3-methylisoxazole (1) with α-halocarbonyl compounds 12 and 14 furnished pyrrolo[3,2-d]isoxazole and isoxazolo[5,4-b]azepin-6-one derivatives 13 and 15, respectively, while reaction of 1 with 1-chloro-4-(chloromethyl)benzene gave the monoalkylated product 17. The newly synthesized compounds were screened for their antitumor activity, and the geometry optimizations are in a good agreement with the experimentally observed data.

Coumarin and their derivatives are important groups of heterocyclic compounds. They have attracted considerable interest because of their great biological importance. This review describes the work on the synthesis and heterocyclization reactions of aminocoumarines. It was found that the cyclocondensation process depended mainly on the chemoselective and regioselectivity states of the enamino skeleton.

Condensation of 2-amino-5-phenyl-5H-thiazolo[4,3-b] [1,3,4] thiadiazoles (1) with some carboxylic acid derivatives furnished corresponding compounds 2–4, respectively. Alkylation of 1 with benzoylchloride and 4-chlorobenzyl chloride afforded thiazolo[4,3-b][1,3,4]thiadiazole derivatives 5 and 6, respectively. Similarly, transformation of 1 with chloroacetyl chloride yielded chloroacetamide derivative 7. The later compound was subjected to react with potassium thiocyanate or piperazine whereby, the binary thiazolidinone derivative 8 and N1,N4-disubstituted piperazine 9 were produced, respectively. Also, the reactivity of 1 toward various active methylene reagents was investigated. Accordingly, our attempts to synthesize the tricyclic heterocyclic system 10, 11′, 12′ by reaction of 1 with chloroacetonitrile, 4-oxo-4-phenylbutanoic acid and/or diethylmalonate in presence of acetyl chloride was furnished 10, 11, and 12. The newly synthesized compounds were screened as antimicrobial agent.

Chemical reactivity of 2-methyl-2-phenyl-1,3-oxathiolan-5-one (1) toward various reagents such as hydroxyaldehyde, ketone, α,β unsaturated carbonyl compounds, heterocyclic amine, hydrazine, and hydrazide to give unpredicative opened and fused heterocyclic systems was investigated. Moreover, treatment of compound 1 with bromoester to afford the respective fused system, 2-methyl-2-phenylfuro[3,2-d][1,3]oxathiol-5(6H)-one (6) was implemented. Besides, 1H–1H nuclear overhauser effect spectroscopy was used for full confirmation of the compound 19. In addition, the density functional theory modeling study outcomes were discussed and all of the new synthesized compounds were evaluated as antioxidants and cytotoxicity assay against hepatocellular carcinoma cell line.

This review covers many reports of the applications of multicomponent domino reactions (MDRs) in the synthesis of novel stereocontrolled mercapto-heterocycles from the 1972 up to the end of 2016. The reported approaches were employed for modifications of the oxathiolanone core for new construction of a mercapto-heterocycles scaffold from mercaptoacetyl transfer agent with various reagents.

α, β-Unsaturated carbonyl compounds 2a, 2b, 3, and 4 were synthesized by the Knoevenagel condensation between 2-substituted quionoline-3-carboxaldehyde 1a and/or 1b with active methylene compounds. In addition, the synthesis of azlactone is achieved starting from 1a and N-acetylglycine. Synthesis of pyridine, pyrene, and pyrimidine derivatives 6–8 were accomplished via one-pot multicomponent reaction of 1b with acetyl acetone, malononitrile, and ammonium acetate; acetophenone, malononitrile, and NaOH; or acetyl acetone and urea in acidic medium. The new synthesized compounds showed good antimicrobial activities. The DFT calculations have been used to predict the electronic properties of the studied compounds.

We exploited the utilization of 2-methyl-2-phenyl-1,3-oxathiolan-5-one (1) that acts as activated thioglycolic acid as mercaptoacetyl transfer agent to build new pyridinonethiol derivatives via multicomponent domino reactions of 1 with different acyclic or cyclic α,β-unsaturated carbonyl compounds and aniline using CeCl3∙7H2O/KI as Lewis acid catalyst. Furthermore, the new synthesized compounds were biologically evaluated for antitumor efficiency. The geometries and normal modes of vibrations obtained from calculations are in good agreement with the experimentally observed data.

The reaction of 5-amino-3-methylisoxazole () with formalin and secondary amines gave the corresponding Mannich bases . Alkylation of isoxazole derivative with Mannich bases hydrochloride gave unsubstituted isoxazolo[5,4-b]pyridine derivatives via alkylation at position 4. Moreover, coupling reaction of with different diazonium salts gave the corresponding mono and bisazo dyes of isoxazole derivative. The newly synthesized compounds were screened for their antitumor activity compared with 5-fluorouracil as a well-known cytotoxic agent using Ehrlich ascites carcinoma cells. Interestingly, the obtained results showed clearly that compounds , , , , , and exhibited high antitumor activity than 5-fluorouracil.

The reaction of 5-amino-3-methylisoxazole () with aldimines gave basic side chain 5-amino-3-methylisoxazole derivatives . Annulations of derivatives with anisaldehyde afforded the target isoxazolo[5,4-d]pyrimidines . Treatment of with isatin ketimine anil resulted in the formation of derivative , which further cyclized with anisaldehyde afforded the spirotetracyclic system . Mannich reaction of with primary amine such as methylamine and benzylamine gave the corresponding isoxazolo[5,4-d]pyrimidine derivatives and , respectively. The newly synthesized compounds were tested for their antitumor activity.

The reaction of 4-aminocoumarin (2) with benzaldehyde gave the bisenamino derivatives 4. Thus, transamination of 2 with o-phenylenediamine furnished enamino skeleton 3, which can be obtained from 1. Reaction of 1 with 5-aminoisoxazole afforded 5. While reaction of 2 with benzalaniline, isatinanil and phenyl isothio cyanate afforded the corresponding 7, 8 and 9, respectively. Heterocyclic annulations of 2-phenylthiazolidine-4-one 10 2-phenylthiazolidin-4-one 10 and 2-phenyl-thiazinan-4-one 11 systems were achieved via reaction of 2 with benzaldehyde and rather either 2-mercaptoacetic acid or 3-mercaptopropanoic acid respectively. The behavior of 2 towards monochloro acetic acid and 4-oxo-4-phenylbuatonic 4-Oxo-4-phenylbutanoic acid was investigated. All of the newly synthesized compounds were evaluated as antitumor (cytotoxic) agents. Most of these compounds have shown significant antitumor activities.

The reaction of 4-aminocoumarin (2) with appropriate α,β-unsaturated ketones gave the corresponding coumarin [4,3-b]pyridines. Thus, treatment of 2 with (E)-3-(4-nitrophenyl)-1-phenylprop-2-en-1-one, (1E,4E)-1,5-diphenylpenta-1,4-dien-3-one, (Z)-ethyl 3-(4-chlorophenyl)-2-cyanoacrylate, and (2E,6E)-2,6-dibenzylidenecyclohexanone (3, 6 and 12) afforded the corresponding coumarino[4,3-b]pyridines 5, 7 and coumarino[4,3-b]quinoline derivatives 13, respectively. Heterocyclic annulations of coumarino [5,4-b]pyridine system were achieved via reaction of 2 (in situ) with benzylidene derivatives of indandione to give 15 which was also obtained by multicomponent condensation reaction of 2 (in situ) with indandione and benzaldehyde. A representative sample of new synthesized compounds was evaluated as cytotoxic agents.

This review article is a survey of the literature on aminoisoxazoles. It describes the methods of synthesis and chemical reactions of aminoisoxazoles as building blocks for the synthesis of polyfunctionalized heterocyclic compounds.

The reaction of 4-aminocoumarin (2) with benzaldehyde gave the bisenamino derivatives 4. Thus, transamination of 2 with o-phenylenediamine furnished enamino skeleton 3, which can be obtained from 1. Reaction of 1 with 5-aminoisoxazole afforded 5. While reaction of 2 with benzalaniline, isatinanil and phenyl isothio cyanate afforded the corresponding 7, 8 and 9, respectively. Heterocyclic annulations of 2-phenylthiazolidine-4-one 10 2-phenylthiazolidin-4-one 10 and 2-phenyl-thiazinan-4-one 11 systems were achieved via reaction of 2 with benzaldehyde and rather either 2-mercaptoacetic acid or 3-mercaptopropanoic acid respectively. The behavior of 2 towards monochloro acetic acid and 4-oxo-4-phenylbuatonic 4-Oxo-4-phenylbutanoic acid was investigated. All of the newly synthesized compounds were evaluated as antitumor (cytotoxic) agents. Most of these compounds have shown significant antitumor activities.

The reaction of 5-amino-3-methylisoxazole with appropriate α,β-unsaturated ketones gave the corresponding isoxazolo[5,4-b]pyridines. Treatment of 1 with 2,6-dibenzylidenecyclohexanone or 2-benzylidenedimedone afforded the corresponding isoxazolo[5,4-b]quinoline derivatives. 4,6,8,9-Tetrahydroisoxazolo[5,4-b]quinolin-5-one derivative was also obtained by multicomponent condensation reaction of 1 with dimedone and benzaldehyde. Heterocyclic annulation of the isoxazolo[5,4-b]pyridine system was achieved via reaction of 1 with benzylidene derivatives of indandione, quinuclidone, pyrazolone, and oxazolone. A representative of some newly synthesized compounds was evaluated as antitumor agents.

This review article is a survey of the literature on aminoisoxazoles. It describes the methods of synthesis and chemical reactions of aminoisoxazoles as building blocks for the synthesis of polyfunctionalized heterocyclic compounds.

A variety of isoxazolopyridine derivatives and related compounds are synthesized starting from 5-amino-3-methylisoxazole (I).