Bakr F. Abdel-Wahab

Design and synthesis of new 4-pyrazolin-3-yl-1,2,3-triazoles and 1,2,3-triazol-4-yl-pyrazolin-1-ylthiazoles as potential antimicrobial agents.

New pyrazolyl-1,2,3-triazoles and 1,2,3-triazol-4-yl-pyrazolylthiazoles were synthesized through multi step reactions using 1-tolylyl-4-acetyl-5-methyl-1,2,3-triazole as a precursor. All the newly synthesized compounds were characterized by spectral and elemental analyses. The structure of 11b was evidenced by X-ray crystallographic study. The newly synthesized compounds were evaluated for their antimicrobial activities and also their minimum inhibitory concentration (MIC) against most of test organisms was performed. Amongst the tested compounds 5a, 5c, 11b and 11c displayed excellent antimicrobial activity.

Stereoselective Synthesis and Antiviral Activity of (1E,2Z,3E)-1-(Piperidin-1-yl)-1-(arylhydrazono)-2-[(benzoyl/benzothiazol- 2-oyl)hydrazono]-4-(aryl1)but-3-enes

The reaction of benzoyl hydrazine 1a or benzothiazole‐2‐carbohydrazide 1b with 2‐oxo‐N‐arylpropanehydrazonoyl chlorides 2a–d yielded (1Z,2E)‐2‐[(benzoyl/benzothiazol‐2‐oyl)hydrazono]‐N‐(aryl)propanehydrazonoyl chlorides 3a–e. The reaction of 3a–c with sodium benzenesulphinate furnished sulphones 5a–c while the reaction of 5d, e with hydroxyl amine afforded hydroxomoyl derivatives 6a, b. The one‐pot sterioselective reaction of N‐(aryl)propanehydrazonoyl chlorides 3 with certain aromatic aldehydes in the presence of piperidine resulted in the formation of (1E,2Z,3E)‐1‐(piperidin‐1‐yl)‐1‐(arylhydrazono)‐2‐[(benzoyl/benzothiazol‐2‐oyl)hydrazono]‐4‐(aryl1)‐but‐3‐enes 7a–g. X‐ray analysis of piperidinyl amidrazone 7g showed a conversion of its geometrical structure with respect to that of compound 3 and confirmed the stereoselectivity of the latter reaction. The piperidinyl amidrazones 7a–g possessed a significant antiviral activity against herpes simplex viruses (HSV‐1). Compound 7d reduced the number of viral plaques of herpes simplex type‐1 (HSV‐1) by 67%, with respect to the effect of reference drug Aphidicolin.

Groebke–Blackburn–Bienaymé multicomponent reaction: emerging chemistry for drug discovery

The Groebke–Blackburn–Bienaymé reaction (GBBR) is used for the one-pot synthesis of therapeutically relevant fused imidazoles bridgehead nitrogen heterocyclic compounds from readily available aldehyde, isocyanide and amidine building blocks. The reaction is driven by a wide range of catalysts and can be performed either under solvent or solvent-free conditions, or under microwave irradiation as heat source. The GBBR products can be used for the synthesis of a variety of more complex scaffolds via postmodification reactions. These include cyclization and nucleophilic substitution as well as further MCRs. The GBBR reaction has seen diverse applications in combinatorial and medicinal chemistry and its products are of great use in drug discovery. In this review, we summarize the efforts of the chemistry community in the progress and applications of GBBR since 1998. This review also includes some biological profiles and synthetic scopes of GBBR products. The component variations, postmodifications and secondary transformations will also be discussed throughout this review.

3-Acetylindoles: Synthesis, Reactions and Biological Activities

This review deals with synthesis and reactions of 3-acetylindoles as well as their biological activities. The data published over the last few years on the methods of synthesis and chemical properties of 3-acetylindoles are reviewed here for the first time. 3-Acetylindole derivatives have been in the centre of at- tention of researchers over many years due to the high prac- tical value of these compounds, in the first place, the unusu- ally broad spectrum of biological activities. For example, 4- (1H-indol-3-yl)-2-hydroxy-4-oxobut-2-enoic acid was useful as anti-HIV agent, other compounds derived from 3-acetylindoles used in the treatment of gastrointestinal, car- diovascular and CNS disorders, and also used as HIV-1 inte- grase inhibitors. Despite this importance, 3-acetylindoles have not been previously reviewed. The main purpose of this review is to present a survey of the literature on 3- acetylindoles chemistry and provides useful and up-to-date data for medicinal chemists.

2-Acetylbenzofurans: synthesis, reactions and applications

This review deals with synthesis and reactions of 2-acetylbenzofurans. Some of these reactions have been applied successfully to the synthesis of biologically important compounds. The main purpose of this review is to present a survey of the literature on 2-acetylbenzofurans chemistry and provides useful and up-to-date data for their applications since such compounds have not been previ- ously reviewed.

Application of Benzoylaceteonitrile in the Synthesis of Pyridines Derivatives

This review deals with synthetic potential and utility of benzoylacetonitrile in the synthesis of pyridine derivatives. The reac- tions are subdivided into groups that cover the synthetic methods of pyridine derivatives from benzoylacetonitrile e.g. self condensation, Friedlander reaction, Michael Addition reaction, addition to enaminones, reaction with enamino-nitriles or enamino-esters, and one-pot three component reactions. A brief account on the synthesis of benzoylacetonitrile was also displayed.

2-Chloroquinoline-3-carbaldehyde II: Synthesis, Reactions, and Applications

This review deals with synthesis and reactions of 2-chloroquinoline-3-carbaldehyde during the period from 1979 to 1999. The reactions are subdivided in groups that cover the reactions of chloro- and aldehyde substituent as well as reactions which involve both groups. Some of these reactions have been applied successfully to synthesis of biologically important compounds. The main purpose of this review is to present a survey of the literature on 2-chloroquinoline-3-carbaldehyde chemistry and provide useful and up-to-date data for organic and medicinal chemist since such compound has not been previously reviewed in this period.

Utility of 2,4-dioxoesters in the synthesis of new heterocycles

This review deals with synthesis and reactions of 2,4-dioxoesters. Some of these reactions have been applied successfully to the synthesis of biologically important compounds. The data published over the last years on the methods of synthesis and chemical properties of 2,4-dioxoesters are reviewed here for the first time.

Azolylthiadiazoles and benzazolylthiadiazoles

Several thiadiazoles exhibit diverse biological properties such as antimicrobial (1), antitubercular (2), anti-inflammatory (3) and anticonvulsant (4, 5) behavior. The linkage of a thiadiazole ring with different azole and benzazole moieties by one single covalent bond gives rise to a class of heterocyclic systems known as azolylthiadiazoles that also have diverse biological activities. For example, megazole “2-amino-5-(1-methyl-5-nitro-2-imidazolyl)-1,3,4-thiadiazole” has a broad spectrum of antiprotozoan and antibacterial activities (6); 1,3,4-thiadiazole-2,5-dipyrroles are useful in antistatic packaging, sensors and moldings (7); and 5-(5-hydroxy-3-methyl-2oxoimidazolidin-1-yl)-N ,N-dimethyl-1,3,4-thiadiazole-2-sulfonamide is useful as a herbicide (8). The chemistry of azolylpyrazoles (9), but not the chemistry of azolylthiadiazole, has been previously reviewed, despite the versatility of the latter compounds. In this review, the azolylthiadiazole systems have been classified according to the type of the azole nucleus linked to thiadiazole.

Synthetic routes to thiazoloquinazolines

Thiazoloquinazoline scaffold constitutes a promising source of inspiration for the synthesis of novel bioactive molecules. The current review article summarizes the most recent synthetic routes toward thiazoloquinazoline derivatives, published between the years 1983 and 2016. According to the position of fusion between thiazole and quinazoline rings, the thiazoloquinazoline derivatives in this review were classified into seven major types.