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In examining for unique insecticidal agents, two derivatives namely, 2-((3-cyano-4,6-distyrylpyridin-2-yl)thio)-N-(4-nitrophenyl)acetamide (2) and 3-amino-N-(4-nitrophenyl)-4,6-distyrylthieno[2,3-b]pyridine-2-carboxamide (3) were synthesized from distyrylpyridine-2-thione (1). The new compounds were structurally clarified by spectral and elemental analysis data. The insecticidal activity of these compounds were carried out against cowpea aphid, Aphis craccivora Koch. It is demonstrated that the compounds 2 and 3 have noteworthy insecticidal activity against nymphs of cowpea aphid with LC50 values of 0.025-0.027 ppm and 0.005-0.006 ppm after 24 h and 48 h of treatment, respectively. Also, the compounds 2 and 3 have noteworthy insecticidal activity against adults of cowpea aphid with LC50 values of 0.112-0.129 ppm and 0.014-0.015 ppm after 24 h and 48 h of treatment, respectively, that were comparable to that of the control acetamiprid.

Oxygen-containing heterocycles are largely distributed in natural and synthetic compounds. Coumarins are among the most famous heterocycles which possess one oxygen atom in their rings. Coumarins are classified as multifunctional scaffold and are used as anti-oxidant reagents, anti-inflammatory, anti-microbial, anti-fungal, anti-HIV active, analgesic, anti-histaminic, insecticides, dyes, herbicides, sensitizers, perfumes, cosmetics and food additives. Due to their diverse applications in industrial and pharmaceutical fields, many chemists have given significant interest to these compounds. Herein, the review highlights various methods for the synthesis and interactions of coumarin moiety as one of the most efficient categories of heterocycles.

Thiazolopyrimidnes are considered one of the most interesting classes in heterocyclic chemistry due to their pharmaceutical importance. Herein, we report the synthesis of some new heterocyclic compounds containing thiazolopyrimidine starting from compound (1) which was previously prepared in literature. The starting compound was allowed to react with different alkylating agents such as chloroacetone, chloroacetyl chloride, and phenacyl bromide to afford derivatives (2-4). Compound (5), benzylidene derivative, was obtained by the reaction of compound (2) with benzaldehyde while amino-dicarbonitrile compound (6) can be obtained by the reaction of compound (5) and malononitrile. Acetylation of amino group in compound (6) with chloroacetyl chloride led to formation of compound (7). Nucleophilic substitution of chlorine in compound (7) by aniline gave compound (8) which further subjected the Munich reaction to form compound (9). All new synthesized compounds were characterized using different elemental and spectral analysis.

Diclofenac is considered one of the best drugs used as anti-inflammatory agent, so in the present work new diclofenac derivatives containing bioactive moieties, such as triazole, oxadiazole, and thiadiazol, were synthesized. The structures of the new compounds were established based on spectral and elemental analysis. The new synthesized compounds were tested against anti-inflammatory agents and exhibited high activity as expected. The binding position of new diclofenac derivatives toward Cox-1 and Cox-2 enzymes was proved by molecular docking. Also, some of the new compounds were tested against bacteria and displayed high activity.

Different methods for the synthesis of pyridine derivatives as well as the chemical reactivity profiles and structures of these substances are reviewed. The utility of these compounds as precursors is emphasized in the synthesis of many heterocycles that are pharmacologically active organic compounds and agrochemicals. This review results from a literature survey containing some synthetic methods and applications of pyridine derivatives.

Nowadays heterocyclic compounds containing pyrimidine scaffold attract the interest of many organic chemists due to their strong biological activity, so herein we present the synthesis of new polyc...

Biocompatible luminogens with aggregation-induced emission (AIE) have several applications in the biology field, such as in detecting biomacromolecules bioprobes and in bio-imaging. Due to their bioactivities and light-emitting properties, many heterocyclic compounds are good candidates for such applications. However, heterocyclic π-conjugated systems with AIE behavior remain rare as strong intermolecular π–π interactions usually quench their emission. In this work, new thienopyrimidine heterocyclic compounds were synthesized and their structures were verified by elemental analysis and Fourier transform infrared (FT-IR), 1H nuclear magnetic resonance (NMR), and 13C NMR spectra. The photophysical properties of some compounds were investigated in the solution and solid states. Density functional theory calculations were also performed to confirm the observed photophysical properties of the compounds. The studied dyes displayed AIE properties with spectral shapes related to the aggregate structure and a quantum yield up to 10.8%. The emission efficiency of the powder is attributed to the incorporation of multiply rotatable and twisted aryl groups to the fused heterocyclic moieties. The dyes also showed high thermal stability and potent antimicrobial activities against numerous bacterial and fungal strains. Additionally, the cytotoxicity of the new compounds was evaluated against the Caco-2 cell line, and molecular docking was used to investigate the binding conformation of the most effective compound with the MNK2 enzyme. Therefore, the presented structures may potentially be used for bioapplications.

A novel series of 5-amino-6-substituted-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]selenolo[3,2-e]pyrazines (3a–e) was synthesized by the reaction of the chloro pyrazolo[3,4-b]pyrazine carbonitrile 1 with selenium element in the presence of sodium borohydride and ethanol, followed by the reaction with α-halo alkylating agents to produce the selanyl-alkylated derivatives 2a–e. The latter compounds underwent Thorpe-Ziegler cyclization upon heating with ethanolic sodium ethoxide solution to afford the target selenolopyrazolopyrazine compounds. The 5-amino-3-methyl-1-phenyl-1H-pyrazolo[3,4-b]selenolo[3,2-e]pyrazine-6-carboxamide (3b) was used as a versatile precursor for synthesis of new heterocyclic fused to the pyrazoloselenolopyrazine moiety namely: pyrimidine and imidazopyrimidine. Assignment of the chemical structures for the newly synthesized compounds was confirmed on the bases of elemental and spectral techniques including FT-IR, 1H NMR, 13C NMR, and mass spectra. Furthermore, certain compounds were screened for their antimicrobial activity which revealed remarkable activities against various pathogenic strains of bacteria and fungi. Alternatively, some of these compounds exhibited promising anticancer action against some colon and breast cancer cells.

We describe a simple method to synthesize novel 4-cyano-1-morpholin-4-yl-6,7-dihydro-5H-cyclopenta[c]pyridine-3-thione by the reaction of 3-amino-1-thioxo-1,5,6,7-tetrahydrocyclopenta[c]thiopyran-4-carbonitrile with morpholine through Dimroth rearrangement. The 1-amino-5-morpholin-4-yl-7,8-dihydro-6H-cyclopenta[d]thieno[2,3-b]pyridine-2-carboxamide, which was synthesized by two methods, was used as a versatile precursor for synthesis of new thienopyrimidines fused to cyclopenta[d]pyridine ring system. Consequently, reaction of the amino-carboxamide with diethylmalonate, triethyl orthoformate, and cycloalkanones afforded the corresponding fused pyrimidine heterocycles. On the other hand, chloroacetylation of the amino-carboxamide using chloroacetyl chloride in dioxane produced the chloroacetyl amino derivative that in turn underwent cyclocondensation upon reaction with acetic anhydride to give the chloromethyl pyrimidinone. The latter compound was subjected to react with various nitrogen nucleophiles by nucleophilic substitution reactions to yield the akyl (aryl)amino methyl pyrimidinones. Subsequently, treatment of the phenyl aminomethyl derivative with formaldehyde under Mannich conditions produced the imidazopyridothienopyrimidine ring system. Similarly, reaction of the phenyl aminomethyl pyrimidonone with chloroacetyl chloride afforded a new heterocyclic system namely, cyclopentapyridothienopyrimidopyrazine. On the other hand, reaction of the amino-carboxamide with carbon disulfide in pyridine led to the formation of oxopyrimidine thione, which was alkylated by the reaction with different α-halo carbonyl compounds. The newly synthesized compounds were fully characterized on the basis of elemental and spectral analyses. Alternatively, some of these compounds revealed promising antibacterial and antifungal activities through the in vitro screening.

Due to the biological importance of diclofenac derivatives which are included in the composition of the active substance in many medicines used in the treatment of infections. Herein, we present a facile procedure for the synthesis of a new series of diclofenac analogous, in excellent isolated yields starting from the carbohydrazide precursor 1. Acylation and condensation of NH2 group in the starting material with different reagents delivered compounds (2–5). Moreover, the Nucleophilic substitution of chloromethyl derivative 5 with primary and secondary amines gave compounds (6a, 6b, and 7). Furthermore, the hydrazine compound (7) reaction with benzaldehyde and chloroacetylchloride produced derivatives (8, 9). The chemical structures of all newly synthesized compounds have been proved based on elemental and spectral analysis techniques (FTIR, 1HNMR, 13CNMR, and Mass spectroscopy). All synthesized compounds were investigated for their in-vitro antimicrobial activity against different strains of bacteria and fungi in moderate to high activity. A molecular docking approach was utilized to investigate the proposed molecular mechanism of the antibacterial and antifungal activity of the synthesized compounds.

Schiff bases represent an essential class in organic chemistry with antitumor, antiviral, antifungal, and antibacterial activities. The synthesis of Schiff bases requires the presence of an organic base as a catalyst such as piperidine. Base-free synthesis of organic compounds using a heterogeneous catalyst has recently attracted more interest due to the facile procedure, high yield, and reusability of the used catalyst. Herein, we present a comparative study to synthesize new Schiff bases containing indole moieties using piperidine as an organic base catalyst and Au@TiO

Herein, we describe the synthesis of novel piperidinyl thieno tetrahydroisoquinolines attached or fused to other new heterocycles. The diazotization of the previously synthesized pyrrolyl carbohydrazide 1 followed by several reactions with ethanol, aniline and heterocyclization after boiling in dry xylene under Curtius rearrangement conditions yielded the corresponding carbamate, phenyl urea and pyrazino derivatives 3–5. Furthermore, the condensation of 1 with various aromatic aldehydes and ethyl acetoacetate afforded the consistent Schiff's bases 6a-c and 7. The ring closure of the ethyl butanoate ester 7 furnished pyrazolyl compound 8 after heating in an ethanolic sodium ethoxide solution. Moreover, the nucleophilic addition of the carbohydrazide 1 to carbon disulfide in pyridine produced oxadiazolyl thione 9 which was reacted with ethyl chloroacetate to give ethyl sulfanyl acetate ester 10. The assignments of the chemical structures of these new heterocycles were confirmed by using elemental and spectral analysis. Alternatively, selected compounds were examined for antibacterial and antifungal screening. The results revealed highly promising influences against the nominated pathogenic strains.

A novel series of 1-amino-2-substituted-5-piperidinyl-6,7,8,9-tertahydrothieno[2,3-c]isoquinolines (4a–e) was synthesized upon treatment of 4-cyano-1-piperidinyl-5,6,7,8-tetrahydroisoquinline-3(2H)-thione (2) with α-halo carbonyl compounds such as chloroacetone, ethyl chloroacetate, 2-bromoacetophenone, chloroacetamide, and chloroacetanilide. Construction the pyrrolyl ring associated with the thienotetrahydroisoquinoline moiety was achieved by treatment of compounds 4a, b with 2,5-dimethoxytertahydrofuran in acetic acid. 1-Pyrrolyl-2-substituted-thieno[2,3-c]isoquinolines 5a and 5b which in turn were used as multipurpose precursors for synthesis of other new heterocycles. Assignments of the chemical structures of the respectively synthesized thienotetrahydroisoquinolines and their derivatives were established on the bases of elemental and spectral techniques (Fourier transform infrared, 1H NMR, 13C NMR, and mass spectroscopy). Furthermore, certain compounds were screened for their antimicrobial activity which revealed promising activities against various pathogenic strains of bacteria and fungi.

Exopolysaccharides (EPS) particularly, from Lactic acid bacteria have received increasing attention in food, medical, and pharmaceutical applications. The present work aims to isolate, characterize and identify exopoly saccharide-producing bacteria from fermented fruits and vegetables and dairy products. A total of 55 isolates were isolated from fermented fruits, vegetables, and dairy products depending on the mucoid appearance of the colonies. Based on total EPS production, the most promising nine strains were selected, phenotypically and genotypically characterized. They were facultative anaerobe, arranged in pairs/chains (cocco bacillus), oxidase, and catalase-negative, non-spore forming and non-motile Gram-positive bacteria. All the strains were capable of growing at optimum pH between 5-7, tolerate to NaCl up to 7% (w/v), growing at 20-37°C with optimum growth at 30°C, no growth was observed at 45°C. In addition they could utilize small range of organic compounds, except isolate S1 was differ from the others by their ability to utilize a varied range of organic compounds. Construction of phylogenetic tree, on the basis of partial 16S rRNA gene sequences indicated that isolate S1 was similar to Leuconostoc citreum with similarity of 91.3%, while, isolates S2 and S3 were similar to Leu. fallax and Leu. mesenteroides with similarity of 99.40 % and 97.73%, respectively. Isolates S4, S5, S7, S8, and S9 were similar to Leu. holzaapfelii with similarity of 98.3, 98.7 and 99.8, 98.5 and 98.1, respectively, while isolate S6 was similar to Leu. lactis with similarity of 97.9%. None of sugars such as lactose, glucose, and fructose except sucrose were support EPS production from these strains. The highest yield of EPS was recorded for isolates S6, S1 and S7 which were 61.90, 61.80 and 60 gl-1, respectively, followed by isolates S4, S9, S5 and S8 which were 58.40, 53.06, 51.61 and 33.53 gl-1, respectively. Although, the lowest yield was observed for the isolates S3 and S2 which were 22.08 and 18.80 g l-1, respectively. Finally, it could be concluded that EPS production from these strains in the current study, considering them to be the alternative choice for enhancing production of EPS with increased yields, with promising realistic importance in food, pharmaceutical, as well as dairy industries.

New pyrazolothienopyrimidines were synthesized. The key intermediate 4-aminothieno[2,3-c]pyrazole-5-carbonitrile 1 was converted to the chloroacetyl amino derivative 2 followed by nucleophilic substitution and Dimorth rearrangement upon treatment with nitrogen nucleophiles to give the pyrimidinones 3a-c. Treatment of 3a with formaldehyde and with triethyl orthoformate afforded the respective tetracyclic derivatives 4 and 5. Condensation of the amino group in the o-aminocarbonitrile 1 with triethyl orthoformate followed by cycloaddition reaction with hydrazine led to the formation of pyrazolothienopyrimidine 8. Compound 8 was used as a synthetic precursor to heterocyclic compounds comprised of pyrazole, triazole, triazine, and triazepine derivatives.

Heterocyclic compounds play an important role in the field of pharmaceutical chemistry, especially compounds containing hybrid bioactive moieties. So in continuation of our work, We focused mainly here on design, synthesis, and transformations of novel bio-active molecules bearing thieno[2,3-d]pyrimidine moiety which can be used as antibacterial and antifungal drugs after some modifications. The starting compound 2-chloromethyl-3H-7-p-tolylamino-4-oxo-9-phenyl-pyrimido[4',5':4,5]thieno[2,3-d]pyrimidine (1) which was prepared according to literature, was converted into many other derivatives bearing different functional groups to make a comparable study of their antimicrobial activity. The chemical constructions of all obtained compounds were well elucidated by the means of their analytical and spectral analyses (TLC, IR, 1H NMR, 13C NMR, and MS). The title compounds have been chosen and screened for their in vitro antimicrobial efficiency versus some genera of bacteria and fungi, from the practical results we concluded that most of these compounds were powerful antimicrobial agents.

Aim and Objective: We reported in this manuscript, synthesis of novel pyrazolopyrazinothienopyrimidines. The o-amino-thienopyrazolopyrazine-carbonitrile 4 was used as a versatile precursor for synthesis of new heterocyclic compounds. Due to development of resistance to the current antimicrobial therapy and non-steroidal anti-inflammatory drugs (NSAIDs), continues research for more effective agents is interesting. Hence, the suspected promising biological activities of pyrazolopyrazine compounds persuaded us to study the anti-microbial and anti-inflammatory activities in comparison with standard drugs. Materials and Methods: The chemical structures of the newly synthesized compounds were confirmed by elemental and spectral analyses. Activities of the synthesized compounds against a number of Gram-negative and Gram-positive bacterial strains were investigated. The fungal strains were obtained from some cases of human dermatophytosis. The antimicrobial activities were determined according to the Kwon-Chung and Bennett method. Anti-inflammatory activity was evaluated using carrageenan induced paw edema method. Results: The antibacterial screening of the synthesized compounds represented that the o-amino-carbonitrile 4 and triazepinone 11 have the highest activity towards E. coli & S. aureus and S. pneumonia. The amino-imino 6 was very effective against E. coli. Ring closure of 6 to triazolopyrimidine 7 increases the antibacterial activity against E. coli & K. pneumonia, their inhibition zones were higher than ciprofloxacin. Also, the triazolopyrimidines 7 and 10 exhibited high antifungal activity against all tested strains. Compounds 6 and 11 revealed high antifungal activity against S. racemosum and T. rubrum. The anti-inflammatory activity data indicated that all the tested compounds 4, 6, 7, 10 & 11 revealed the highest anti-inflammatory effect after 4 hrs. of carrageenan injection. Conclusion: we found that most of the examined novel thieno- pyrazolopyrazine compounds exhibited promising antibacterial, antifungal and anti-inflammatory activities which can be used as potential antibacterial, antifungal and anti-inflammatory drugs.