Herin we report the design, synthesis, full characterization and biological investigation of new 15-LOX/COX dual inhibitors based on 1,3-thiazolidin-4-one (15-lipoxygenase pharmacophore) and 1,3,4-thiadiazole (COX pharmacophore) scaffolds. This series of molecular modifications is an extension of a previously reported series to further explore the structural activity relationship. Compounds 3a, 4e, 4n, 4q, 7 and 8 capable of inhibiting 15-LOX at (2.74, 4.2, 3.41, 10.21, 3.71 and 3.36 μM, respectively) and COX-2 at (0.32, 0.28, 0.28, 0.1, 0.28 and 0.27 μM, respectively). The results revealed that binding to 15-LOX and COX is sensitive to the bulkiness of the substituents at the 5 positions. 15-LOX bind better with small substituents, while COXs bind better with bulky substituents. Compounds 3a, 4r and 4q showed comparable in vivo anti-inflammatory activity to the reference drug (celecoxib). The ulcer liability test showed no sign of ulceration which ensures the safe gastric profile. Docking study was performed to explore the possible mode of interaction of the new compounds with the active site of human 15-LOX and COX-2. This study discloses some structural features for binding to 15-LOX and COX, thus pave the way to design anti-inflammatory agents with balanced dual inhibition of these enzymes.

This study aimed to explore the phytoconstituents of Agonis flexuosa, F. Myrtaceae and its biological activity. A thorough phytochemical investigation of its leaves led to the isolation of one new stilbene glycoside; (Z)-2,3-dihydroxystilbene-5-O-β-D-glucoside (1), and fifteen known compounds identified as two stilbenes: (Z)-pinosylvin mono methyl ether (2) and (Z)-pinosylvin-3-O-β-D-glucoside (3); six flavanones: (2S)-pinostrobin (4), (2S)-strobopinin (5), (2S)-cryptostobin (6), (2S)-pinocembrin (7), (2S)-dimethylpinocembrin (8) and (2S)-dimethylstrobopinin (9); four flavonoids: quercetin (10), kaempferol-7-O-β-D-glucoside (11), quercetin-3-O-α-D-rhamnoside (12) and quercetin-3-O-β-D-glucoside (13), α-terpineol (14), β-sitosterol (15) and gallic acid (16). The structures of the isolated metabolites were elucidated based upon the interpretation of their 1D and 2D NMR (One Dimensional and Two-Dimensional Nuclear Magnetic Resonance), HR-ESI-MS (High Resolution Electrospray Ionization Mass Spectrometry) and optical rotation. All the isolated compounds were evaluated for their antimicrobial activities. Only compound (6) showed a selective activity against P. aeruginosa with IC50 value of 4.88 µM. In silico virtual screening was done for the isolated compounds on Human histamine H1 receptor (3RZE) downloaded from protein data bank. All the compounds showed certain degree of binding to the protein displaying free binding energies ranging between -11 to -31 kcal/mol. (Z)-2,3-Dihydroxystilbene-5-O-β-D-glucoside (1) showed notable fitting to the active site as evidenced by its free binding energy (∆G) which is computed as -25.09 kcal/mol comparable to diclofenac that displayed (∆G) of -15.00 kcal/mol. In vitro assessment of histamine release inhibitory activity was performed using U937 human monocytes. Compound (1) showed a substantial inhibition to histamine release displaying IC50 value of 0.16 μM.

A hybrid pharmacophore approach is used to design and synthesize two novel series of 2′-hydroxychalcone-triazole hybrid molecules 6a-j and 8a-j. These compounds were fully characterized by spectral and elemental analyses. They were evaluated in vitro and in vivo for anti-inflammatory activity. Most of compounds were selective inhibitors for COX-2. Among them, compounds 6d, 6f, 6i, 8c, 8e and 8h demonstrated highly potent dual inhibition of COX-2 (IC50 = 0.037–0.041 µM) and 15-LOX (IC50 = 1.41–1.80 µM). Compounds 6i, 8c and 8h showed 116%, 113% and 109% of the in vivo anti-inflammatory activity of celecoxib. Therefore, compounds 6d, 6f, 6i, 8c, 8e and 8h-j are potent dual inhibitors of COX-2 and 15-LOX. Docking study over COX-2 and 15- LOX active sites ensures the binding affinity and selectivity. These compounds are promising candidates for further development as anti-inflammatory drugs.

A hybrid pharmacophore approach is used to design and synthesize two novel series of 2′-hydroxychalcone-triazole hybrid molecules 6a-j and 8a-j. These compounds were fully characterized by spectral and elemental analyses. They were evaluated in vitro and in vivo for anti-inflammatory activity. Most of compounds were selective inhibitors for COX-2. Among them, compounds 6d, 6f, 6i, 8c, 8e and 8h demonstrated highly potent dual inhibition of COX-2 (IC50 = 0.037–0.041 µM) and 15-LOX (IC50 = 1.41–1.80 µM). Compounds 6i, 8c and 8h showed 116%, 113% and 109% of the in vivo anti-inflammatory activity of celecoxib. Therefore, compounds 6d, 6f, 6i, 8c, 8e and 8h-j are potent dual inhibitors of COX-2 and 15-LOX. Docking study over COX-2 and 15- LOX active sites ensures the binding affinity and selectivity. These compounds are promising candidates for further development as anti-inflammatory drugs.

A hybrid pharmacophore approach is used to design and synthesize two novel series of 2′-hydroxychalcone-triazole hybrid molecules 6a-j and 8a-j. These compounds were fully characterized by spectral and elemental analyses. They were evaluated in vitro and in vivo for anti-inflammatory activity. Most of compounds were selective inhibitors for COX-2. Among them, compounds 6d, 6f, 6i, 8c, 8e and 8h demonstrated highly potent dual inhibition of COX-2 (IC50 = 0.037–0.041 µM) and 15-LOX (IC50 = 1.41–1.80 µM). Compounds 6i, 8c and 8h showed 116%, 113% and 109% of the in vivo anti-inflammatory activity of celecoxib. Therefore, compounds 6d, 6f, 6i, 8c, 8e and 8h-j are potent dual inhibitors of COX-2 and 15-LOX. Docking study over COX-2 and 15- LOX active sites ensures the binding affinity and selectivity. These compounds are promising candidates for further development as anti-inflammatory drugs.

A hybrid pharmacophore approach is used to design and synthesize two novel series of 2′-hydroxychalcone-triazole hybrid molecules 6a-j and 8a-j. These compounds were fully characterized by spectral and elemental analyses. They were evaluated in vitro and in vivo for anti-inflammatory activity. Most of compounds were selective inhibitors for COX-2. Among them, compounds 6d, 6f, 6i, 8c, 8e and 8h demonstrated highly potent dual inhibition of COX-2 (IC50 = 0.037–0.041 µM) and 15-LOX (IC50 = 1.41–1.80 µM). Compounds 6i, 8c and 8h showed 116%, 113% and 109% of the in vivo anti-inflammatory activity of celecoxib. Therefore, compounds 6d, 6f, 6i, 8c, 8e and 8h-j are potent dual inhibitors of COX-2 and 15-LOX. Docking study over COX-2 and 15- LOX active sites ensures the binding affinity and selectivity. These compounds are promising candidates for further development as anti-inflammatory drugs.

The applicability of ninhydrin, a widely used derivatizing reagent, for determination of teicoplanin (TEIC) in its pure form, pharmaceutical vials, and in human plasma was investigated. The presented spectrofluorimetric method was based on a condensation reaction between ninhydrin and the primary amine group existing in TEIC (in the presence of phenylacetaldehyde) to produce a highly fluorescent product detected at 460 nm (λex,390 nm). Calibration plots were constructed in the concentration range 60–600 ng mL–1 with a good correlation coefficient of 0.9998 and a low detection limit of 10.84 ng mL–1. The method was subjected to a bioanalytical validation study according to US‐FDA recommendations. The proposed method was applied for analysis of TEIC in commercial vials with high recovery result 101.88 ± 1.11%. In addition, the method was utilized efficiently for detection of TEIC in human plasma using salting‐out assisted liquid–liquid extraction technique (SALLE) with a recovery range from 96.71 ± 1.08% to 97.71 ± 0.86%. SALLE is an effective approach used for extraction of TEIC from human plasma without interferences using ammonium sulphate. The proposed method is highly recommended to monitor TEIC in clinical laboratory samples and therapeutic drug monitoring systems.

The applicability of ninhydrin, a widely used derivatizing reagent, for determination of teicoplanin (TEIC) in its pure form, pharmaceutical vials, and in human plasma was investigated. The presented spectrofluorimetric method was based on a condensation reaction between ninhydrin and the primary amine group existing in TEIC (in the presence of phenylacetaldehyde) to produce a highly fluorescent product detected at 460 nm (λex,390 nm). Calibration plots were constructed in the concentration range 60–600 ng mL–1 with a good correlation coefficient of 0.9998 and a low detection limit of 10.84 ng mL–1. The method was subjected to a bioanalytical validation study according to US‐FDA recommendations. The proposed method was applied for analysis of TEIC in commercial vials with high recovery result 101.88 ± 1.11%. In addition, the method was utilized efficiently for detection of TEIC in human plasma using salting‐out assisted liquid–liquid extraction technique (SALLE) with a recovery range from 96.71 ± 1.08% to 97.71 ± 0.86%. SALLE is an effective approach used for extraction of TEIC from human plasma without interferences using ammonium sulphate. The proposed method is highly recommended to monitor TEIC in clinical laboratory samples and therapeutic drug monitoring systems.

A selective and highly sensitive high performance liquid chromatography (HPLC) with fluorescence derivatization method was developed for determination of ethinyl estradiol (EE); one of endocrine-disrupting compounds (EDCs). The fluorescence derivatization procedure was based on Sonogashira coupling reaction using 4-(4, 5-diphenyl-1H-imidazole-2-yl) iodobenzene (DIB-I), a fluorescence labeling reagent, to derivatize EE in presence of copper and palladium ions. The formed fluorescent product was separated on Cosmosil 5C18 MS-II by an isocratic elution with a mobile phase composed of acetonitrile: 5.0 mM Tris-HNO3 buffer, pH 7.4 (60:40, v/v %). The detection wavelengths were set at 310 and 400 nm as excitation and emission wavelengths, respectively. Various parameters affecting derivatization reaction were optimized. Further, the proposed method was validated and a good linearity with low detection limit (S/N=3) 7.4 ng L−1 was obtained in water sample after a simple solid-phase disk extraction (C18 SPE disk) method. The proposed method was successfully applied for detection of EE in river water samples in order to monitor EE concentration and to distinguish its effect on the ecosystem and human health.

A potential microtubule destabilizing series of new thirty-five Pyrrol-2-one, Pyridazin-3(2H)-one and Pyridazin-3(2H)-one/oxime derivatives has been synthesized and tested for their antiproliferative activity against a panel of 60 human cancer cell lines. Compounds IVc, IVg and IVf showed a broad spectrum of growth inhibitory activity against cancer cell lines representing renal, cancer of lung, colon, central nervous system, ovary, and kidney. Among them, compound IVg was found to have broad spectrum anti-tumor activity against the tested nine tumor subpanels with selectivity ratios ranging between 0.21 and 3.77 at the GI50 level. In vitro assaying revealed tubulin polymerization inhibition by all active compounds IVc, IVg and IVf. The results of the docking study revealed nice fitting of compounds IVc, IVf, and IVg into CA-4 binding site in tubulin. The three compounds exhibited high binding affinities (Gb = -12.49 to -12.99 kcal/mol) toward tubulin compared to CA-4 (-8.87 kcal/mol). Investigation of the binding modes of the three compounds IVc, IVf, and IVg revealed that they interacted mainly hydrophobically with tubulin and similar binding orientations to that of CA-4. These observations suggest that tubulin is a possible target for these compounds.