Yılmaz Yıldırır

Synthesis and antimicrobial activities of novel bisacridine-1,8-dione derivatives

A series of bisacridine-1,8-dione derivatives were synthesized by one-pot reaction of aromatic dialdehydes, dimedone or cyclohexane-1,3-dione and primer aromatic amines in acetonitrile to utilizing Amberlyst-15 as a heterogeneous catalyst. The structures of compounds were characterized by FT-IR, NMR, and elemental analysis. Antimicrobial activities of these compounds were determined by using the disc diffusion method against to these gram-positive and gram-negative bacteria and yeast. The results were compared with reference discs.

The synthesis and investigation of the antimicrobial activity of some new phenylselanyl-1-(toluene-4-sulfonyl)-1H-tetrazole derivatives

The sulfonamide functional group has aroused interest in both medicinal and bioorganic chemistry. In this study, some new phenylselanyl–1–(toluene-4-sulfonyl)-1H-tetrazole derivatives (2a–f) have been synthesized using dicyclohexylcarbodiimide/dimethylaminopyridine (DCC/DMAP). The structures of the presently synthesized compounds were elucidated by spectroscopic methods [Fourier-transform infrared (FTIR) spectroscopy, 1H nuclear magnetic resonance (NMR), 13C nuclear magnetic resonance-attached proton test (13C NMR-APT), and mass spectrometry (MS)]. In addition, the antimicrobial activity of the synthesized compounds and two antibiotics [sulfamethoxazole (SMX) and sulfamerazine (SRZ)] were investigated against some microorganisms.Graphical AbstractThe synthesis and investigation of the antimicrobial activity of some new phenylselanyl-1-(toluene-4-sulfonyl)-1H-tetrazole derivativesYılmaz Yıldırır, M. Faruk Us, Naki Çolak, Hamdi Özkan, Serkan Yavuz, Ali Disli, Sahlan Ozturk, Lemi TurkerIn this study, some new phenylselanyl–1–(toluene-4-sulfonyl)-1H- tetrazole derivatives, 2a–f, have been synthesized using DCC/DMAP. In addition to, antimicrobial activity of synthesized compounds and two antibiotics (SMX, SRZ) were investigated against some microorganisms. Reagents and conditions: (i) HCI, (ii) EtONO, -5 – 0°C; (iii) KSeCN, (iv) NaN3, Et3NH+ CI−, Toluene. 2a. R1:H, R2:Cl 2b. 2a. R1:H, R2:CH32c. R1:Cl, R2:H 2d. R1:Br, R2:H 2e. R1:I, R2:H 2f. R1:CH3, R2:H

Synthesis, Characterization, and In Vitro Antimicrobial and Antifungal Activity of Novel Acridines

Novel acridines (4a – 4l) were synthesized by reaction of tetraketones (3a, 3b) and aromatic amines. The structures of compounds were characterized by FT-IR, 1H NMR, mass spectroscopy, and elemental analysis. Furthermore, all the synthesized compounds were tested in vitro for their antimicrobial and antifungal activity. The results were compared with conventional reference antibiotics. Many of the acridine compounds considerably reacted against Esherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, and Staphylococcus aureus. Particularly, compound 4k showed more pronounced activity than reference antibiotics against Salmonella enteritidis. All the compounds showed moderate activities against Candida albicans and Candida glabrata.

Synthesis and Pharmacological Evaluation of Some Novel Thebaine Derivatives: N-(Tetrazol-1H-5-yl)-6,14-endoethenotetrahydrothebaine Incorporating the 1,3,4-Oxadiazole or the 1,3,4-Thiadiazole Moiety

In this study, we synthesized some novel N‐(tetrazol‐1H‐5‐yl)‐6,14‐endoethenotetrahydrothebaine 7α‐substituted 1,3,4‐oxadiazole and 1,3,4‐thiadiazole derivatives as potential analgesic agents. The structures of the compounds were established on the basis of their IR, 1H NMR, 13C NMR, 2D NMR, and high‐resolution mass spectral data. The analgesic activity was evaluated by a rat‐hot plate test model and a rat tail‐flick model. Compound 12 showed analgesic activity higher than that of morphine. In addition to a histopathological and biochemical evaluation, the LD50 dose for the most active compound 12 was determined.

Synthesis and antimicrobial activity studies of some novel substituted phenylhydrazono-1H-tetrazol-5-yl-acetonitriles

AbstractIn this study, some substituted phenylhydrazono-1H-tetrazol-5-yl-acetonitriles have been synthesized (2a–o, 2a and 2k are known compounds). The synthesized compounds were characterized by spectroscopic methods [Fourier-transform infrared (FTIR), nuclear magnetic resonance (NMR), mass spectroscopy (MS)]. In addition, antimicrobial activities of synthesized compounds were investigated against Bacillus cereus RSKK 863, Escherichia coli ATCC 3521, Pseudomonas aeruginosa ATCC 2921, and Staphylococcus aureus TP32. These compounds had antimicrobial effect against these bacteria (except for 2l).Graphical AbstractIn this study, some substituted phenylhydrazono-1H-tetrazol-5-yl-acetonitriles have been synthesized (2a-o, 2a and 2k are known compounds, but others are novel). The synthesized compounds were characterized by spectroscopic methods (FTIR, NMR, MS).In addition, antimicrobial activities of synthesized compounds were investigated against Bacillus cereus RSKK 863, Escherichia coli ATCC 3521, Pseudomonas aeruginosa ATCC 2921, and Staphylococcus aureus TP32. These compounds (except for 2l) have antimicrobial effect against these bacteria. Antimicrobial activities of these compounds were compared with antimicrobial activities of some antibiotics.Scheme 1: Protocol for the synthesis substituted phenylhydrazono-1H-tetrazol-5-yl-acetonitriles. (a) R1: H, R2: H; (b) R1: F, R2: H; (c) R1: H, R2: F; (d) R1: Cl, R2: H; (e) R1: H, R2: Cl; (f) R1: Br, R2: H; (g) R1: H, R2: Br; (h) R1: I, R2: H; (i) R1: H, R2: I; (j) R1: CH3, R2: H; (k) R1: H, R2: CH3; (l) R1: OCH3, R2: H; (m) R1: H, R2: OCH3; (n) R1: NO2, R2: H; (o) R1: H, R2: NO2.

The Syntheses of Some Novel (Naphthalen-1-yl-selenyl)acetic Acid Derivatives

Some new (naphthalen-1-yl-selenyl)acetic acids derivatives 7a‑d have been synthesized by two different methods, using naphthylselenols or naphthylselenocyanates. The structures of the products were investigated by spectroscopic methods.

9-(4-Methoxy­phen­yl)-3,3,6,6-tetra­methyl-3,4,6,7-tetra­hydro-2H-xanthene-1,8(5H,9H)-dione

In the molecule of the title compound, C24H28O4, the three six-membered rings of the xanthene system are not planar, having envelope, boat and envelope conformations. In the crystal structure, C—H⋯O hydrogen bonds link the molecules, generating centrosymmetric R 2 2(12), R 4 4(28) and R 2 2(16) ring motifs and forming a three-dimensional network.

Fast method for synthesis of alkyl and aryl-N-methylnitrones.

A simple, fast, efficient and eco-friendly procedure was developed for the synthesis of alkyl and aryl-N-methylnitrones. The corresponding nitrones of aromatic aldehydes, aliphatic aldehydes and alicyclic carbonyl compounds were prepared from N-methylhydroxylamine hydrochloride and Na2CO3-Na2SO4 by simply grinding at room temperature without using solvent.

7α-Methoxy-carbonyl-6,7,8,14-tetra-hydro-6,14-endo-ethenothebaine.

In the molecule of the title compound, C23H27NO5, the furan ring adopts an envelope conformation. Intramolecular C—H⋯O interactions result in the formation of S(5) and S(6) motifs. In the crystal structure, weak intermolecular C—H⋯O hydrogen bonds link the molecules through C(6) and C(8) chains along the [100] and [010] directions, generating a two-dimensional network.

IMPROVED SYNTHESIS OF PHENYLSELENOGLYCOLIC ACIDS

Selenium is a nonmetallic trace element recognized as a nutrient essential to human health.’** Selenium is also an essential constituent of extracellular and cellular glutathione peroxidases, thyroidal and extrathyroidal iodothyronine 5’-deiodinnases, thioredoxin reductase, and other selenoproteins.2 Various experimental models showed that selenium inhibits tum~rigenesis.~ Low serum selenium levels are associated with an increased risk of developing cancer at several sites, especially cancers of the stomach and lung for men4. Thus, many organoselenium compounds have been ~ynthesized.’,~ Some substituted phenylselenoglycolic acids have been synthesized by using Grignard reagent’ (Scheme I) (yields 20-2596) and from