• Bulletin of the Korean Chemical Society
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• v.31 no.5
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• pp.1219-1222
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• 2010

A simple and efficient method has been developed for conversion of arenecarbaldehyde-3-methylquinoxalin-2-ylhydrazones to 3-(2-methylquinoxalin-3-yl)-2-(substitutedphenyl)thiazolidin-4-ones in good yields using microwave irradiation technique on silica as solid support under solvent free conditions. The synthesized compounds were characterized by elemental microanalysis, infrared spectroscopy, $^1H$ NMR, and mass spectroscopy. All the synthesized thiazolidinones were investigated for their antimicrobial and antifungal activities. The results of the biological activities revealed that the compounds 3b, 3d, 3f and 3h exhibited excellent antibacterial activities while 3d and 3h exhibited good antifungal activity.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.82-91
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• 2012

Novel azopyrazolin-5-one dyes 4a-f were synthesized by the regioselective reaction of phenylhydrazine with 2,3,4-chromantrione-3-arylhydrazones 2a-f. The acid dissociation constants $pK_a$ for the series prepared were determined and correlated by the Hammett equation. The results of such correlation together with the spectral data indicated that the studied compounds exist predominantly in the hydrazone keto structure, (D) as the Z-configuration. The dyes were applied to polyester fabrics, affording orange-yellow shades and assessments of their dyeing performance are considered. Further, the compounds 4a-f were screened for their antimicrobial activity against various microorganisms.

• Korean Journal of Medicinal Crop Science
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• v.12 no.3
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• pp.179-182
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• 2004

Bioassay-directed fractionation of the dried roots of Salvia miltiorrhiza led to the isolation of abietane tanshinones, cryptotanshinone and dibydrotanshinone I. Their structures were elucidated using $^1H-\;and\;^{13}C-NMR$, UV, IR and mass spectral analyses. These compounds exhibited a moderate antimicrobial activities against Staphylococcus epidemidis, Staphylococcus aureus, and Staphylococcus pyogene.

• Natural Product Sciences
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• v.10 no.2
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• pp.69-73
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• 2004

Continuation of a phytochemical study of Cichorium intybus L. (Astraceae) growing in Egypt, resulted in the isolation and identification of a new sesquiterpene lactone 3,4-dihydrolactucin, in addition to the eight known compounds; kaempferol, isoscutellarin, cichoriin, umbelliferone, lupeol, lupeol acetate, ${\beta}-sitosterol$, and ${\beta}-sitosterol-3-O-glucoside$. Chemical structures of the isolated compounds were assigned based on different physical, chemical, and spectroscopic techniques including IR, UV, MS, 1D- and 2D-NMR spectra. Furthermore, the antimicrobial, and spasmogenic activities of some fractions and isolates were also assessed.

• YAKHAK HOEJI
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• v.52 no.4
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• pp.274-278
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• 2008

Two known lavandulylated flavanones, leachianone A (1) and sophoroaflavanone G (2), were isolated from the roots of S. flavascens Ait. The structures of these compounds were determined on the basis of IR, 1D and 2D NMR in addition to direct comparison with authentic compounds. However, leachianone A (1) and sophoroflavanone G (2) did not have growth inhibition activity against any microorganisms (MIC, >200 ${\mu}g/ml$).

• Mycobiology
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• v.37 no.1
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• pp.31-36
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• 2009

A phytochemical study on the flower of Calotropis gigantea (Linn.) using silica gel column chromatography and preparative thin layer chromatography, led to the first time isolation of Di-(2-ethylhexyl) phthalate (compound 1) and anhydrosophoradiol-3-acetate (compound 2). The structures of these compounds were confirmed by spectroscopic analyses (IR, HRTOFMS and NMR). The antibacterial and antifungal activities of ethyl acetate extract, compound 1 and compound 2 were measured using the disc diffusion method. Ethyl acetate extract and compound 1 presented better results than compound 2. The minimum inhibitory concentrations (MICs) of the extract and compounds were found to be in the range of $16{\sim}128{\mu}g/ml$. The cytotoxicity ($LC_{50}$) against brine shrimp nauplii (Artemia salina) were also evaluated and found to be 14.61 ${\mu}g/ml$ for ethyl acetate, 9.19 ${\mu}g/ml$ for compound 1 and 15.55 ${\mu}g/ml$ for compound 2.

• Natural Product Sciences
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• v.9 no.2
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• pp.56-59
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• 2003

Chemical studies on the constituents of the leaves of Murraya paniculata (Lynn) Jack have furnished three highly-oxygenated flavonoids; gardenin E (1), gardenin A (2), and gardenin C (3). Structures of the compounds were elucidated based on NMR, MS, UV, IR data and also by comparison with the previous works. The antimicrobial activities of these compounds and the crude extracts were also evaluated.

• Journal of the Korean Chemical Society
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• v.58 no.1
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• pp.57-61
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• 2014

The 4-(1H)-benzotriazoyl methyl amino benzoate 3 was prepared by Mannich reaction of benzotriazole 1, ethyl-paminobenzoate 2 and formaldehyde. The prepared compound 3 then react with hydrazine hydrate results in the 4-(1H)-benzotriazoyl methyl amino benzoyl hydrazide 4. This compound on condensation with pre-prepared different ethyl 2-(2-(4-(4-substituted phenyl)thiazol-2-yl)hydrazono)-3-oxobutanoates 6a-d, furnished 1-(4-((1H-benzo[d] [1,2,3] triazol-1-yl)methyl amino) benzoyl)-4-(2-(4-(4-substituted phenyl)thiazol-2-yl) hydrazono)-3-methyl-1H-pyrazol-5(4H)-one 7a-d. All the compounds 7a-d was characterized by spectral studies. The compounds showed significant antimicrobial activity against various bacteria and fungi.

• Archives of Pharmacal Research
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• v.21 no.5
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• pp.591-594
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• 1998

The structural analogues of cumambrin B(1, 2, 3, 4) were isolated from the flower of Chrysnathemum boreale Makino. The structures of compounds were determined by two-dimensional $^{1}H-^{1}H$ COSY and $^{13}C-^{1}H$ COSY spectra with the aid of homonuclear and heteronuclear double resonance experiment. The stereochemistry of compounds has been verified from single crystal X-ray diffraction of cumambrin A(2). the antimicrobial activities of these guaianolides have been studied.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.179-185
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• 2023

Bauhinia rufescens, Ocimum basilicum and Salvadora persica are well known plants used in African traditional medicine, especially in Chadian traditional medicine. They are mostly used in the treatment of infectious diseases, inflammatory diseases, fever, and so on. Studies using various in vitro and in vivo bioassay techniques support the scientific rationale for most of these usages. In this review, ethnobotanical uses, chemistry of natural products, and pharmacological and clinical data for these plants are presented.