Synthesis and antimicrobial activity of 4-carbethoxymethyl-2-[(alpha-haloacyl)amino] thiazoles and 5-nonsubstituted/substituted 2-[(4-carbethoxymethylthiazol-2-yl)imino]-4-thiazolidinones

4-Carbethoxymethyl-2-[(chloroacetyl/alpha-chloropropionyl/al pha- bromobutyryl/alpha-chloro-(alpha-phenylacetyl)amino]thiazoles (I-IV) were synthesized by reacting 4-carbethoxymethyl-2-aminothiazole with chloroacetyl chloride, alpha-chloropropionyl chloride, alpha-bromobutyryl bromide and alpha-chloro-alpha-phenylacetyl chloride, respectively. Furthermore, I-IV were refluxed with ammonium thiocyanate to give 2-[(4-carbethoxymethylthiazol-2-yl)imino]-4-thiazolidinones (V-VIII). V was refluxed with various aromatic aldehydes to give 5-arylidene-2-[(4-carbethoxymethylthiazol-2-yl)imino]-4-t hiazolidinones (IX-XIV). The structures of synthesized compounds were confirmed by elemental analyses, hydrolysis, UV, IR, 1H-NMR and EI mass spectral data. The antimicrobial activities of the compounds were assessed by microbroth dilution technique using Mueller-Hinton broth and Mueller-Hinton Agar. In this study, Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis and Candida albicans ATCC 10231 were used as test microorganisms. Among the tested compounds, XI and XIV showed activity against S. aureus (MIC: 78 micrograms/ml, 1.6 micrograms/ml), whereas compound V had an activity against S. flexneri (MIC: 39 micrograms/ml) and compound I against C. albicans (MIC: 125 (micrograms/ml). Compounds I, IV-XIV were also evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. Only compounds I and XIV showed 86% and 67% inhibition in the primary screen.     

Synthesis and evaluation of antibacterial activity of some 2-[[alpha-(4-substituted benzoyloxy)-alpha-phenylacetyl or methylacetyl]amino]-5-(4-methoxyphenyl)- 1,3,4-oxadiazoles

In this study, a new series of 1-[[alpha-(4-substitutedbenzoyloxy)-alpha-phenylacetyl or methylacetyl]amino]-5-(4-methoxyphenyl)-1,3,4-oxadiazoles were obtained by condensation of 2-[(alpha-chloro-alpha-phenylacetyl or alpha-bromopropionyl)amino]-5-(4-methoxyphenyl)1,3,4-oxadiazoles with sodium salts of 4-substituted benzoic acids. Structures of the compounds were assigned on the basis of spectral data (UV, IR, 1H NMR, El MS) and elemental analyses. The antibacterial activities of the novel compounds against Staphylococcus aureus ATCC 6538. Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri and Proteus mirabilis and antifungal activity against Candida albicans ATCC 10231 were tested using disk diffusion method. Compounds 4a, 4d and 4g were found to be active against S. aureus ATCC 6538 (MIC, 78, 39 and 78 microg ml(-1), respectively) and compound 4e against S. epidermidis ATCC 12228 (MIC, 156 microg ml(-1)).     

Synthesis and evaluation of antimicrobial and anticonvulsant activities of some new 3-[2- (5-aryl-1,3,4-oxadiazol-2-yl/4-carbethoxymethylthiazol-2-yl) imino-4-thiazolidinon-5-ylidene]-5-substituted/nonsubstituted 1H-indole-2-ones and investigation of their structure-activity relationships

In the present study, 20 new compounds having 3-[2-(5-aryl-1,3,4-oxadiazol-2-yl) imino-4-thiazolidinon-5-ylidene]-5-substituted/nonsubstituted 1H-indole-2-one (I-XII) and 3-[2-(4-carbethoxymethylthiazol-2-yl)imino-4-thiazoldinon-5-ylidenel-5-substituted/nonsubstituted IH-indole-2-one (XIII-XX) systems were synthesized. The structures were confirmed by spectral methods (UV, IR, 1H-NMR, 13C-NMR, 13C-DEPT (135), electron impact mass spectrometry) and elemental analysis. All compounds were tested for in vitro antimicrobial activity against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis ATCC 14153, Candida albicans ATCC 10231, Microsporum gypseum (NCPF-580), Microsporum canis, Trichophyton mentagrophytes and Trichophyton rubrum and some of them were found to be active. Especially, compound I was more active than cefuroxime sodium (CAS 56238-63-2) which was used as a standard, and the activity of compound XII was close to that of cefuroxime sodium against Staphylococcus epidermidis ATCC 12228. Primary screening for antituberculous activity was conducted at 6.25 microg/ml against Mycobacterium tuberculosis H37Rv in BACTEC 12B medium using the BACTEC 460 radiometric system. The anticonvulsant activities of selected prototoype compounds (I, IV-VI, VIII, XI, XIII, XVI-XVIII) administered at doses of 50-200 mg/kg (i.p.) were evaluated using the pentetrazol test (PTZ) in mice.     

Synthesis of some new 6-methylimidazo[2,1-b]thiazole-5-carbohydrazide derivatives and their antimicrobial activities

In this study, 14 new compounds having 6-methyl-N2-(alkylidene/cycloalkylidene)imidazo[2,1-b]thiazole-5-carbohydrazide (3a-g), 3-[[(6-methylimidazo[2,1-b]thiazole-5-yl)carbonyl]amino]-4-thiazolidinone (4a-d) and 4-[[(6-methylimidazo[2,1-b]thiazole-5-yl)carbonyl]amino]-1-thia-4-azaspiro[4.4]nonan/[4.5]decan-3-one (4e-g) structures were synthesized. The structures of the compounds were elucidated by UV, IR, 1H-NMR, 13C-NMR, 1H-13C-COSY, mass spectra and elemental analysis. All compounds synthesized were tested for antimicrobial activity against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri, Proteus mirabilis ATCC 14153, Candida albicans ATCC 10231 and Mycobacterium tuberculosis H37Rv. Only 4d and 4f demonstrated antimicrobial activity against S. epidermidis ATCC 12228 (MIC: 19.5 microg/ml and 39 microg/ml, respectively).     

Synthesis of Mannich bases of some 2,5-disubstituted 4-thiazolidinones and evaluation of their antimicrobial activities

5-Phenyl/methyl-5-morpholinomethyl/pyrrolidinomethyl-2-(5- aryl-1,3,4-oxadiazol-2-yl)imino]-4-thiazolidinones (5a-m) were synthesized by the reaction of 5-phenyl/methyl-2-[(5-aryl-1,3,4-oxadiazol -2-yl)imino]-4-thiazolidinones (4a-j) with formaldehyde and morpholine or pyrrolidine. The structures of the compounds were determined by analytical and spectral (IR, 1H-NMR, EIMS) methods. The antibacterial activities of the novel compounds against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, Escherichia coli ATCC 8739, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Salmonella typhi, Shigella flexneri and Proteus mirabilis and antifungal activity against Candida albicans ATCC 10231 were tested using the disk diffusion method. Compounds 5a, 5b, 5c, 5e, 5g, and 5h were found to be active against S. aureus ATCC 6538 (MIC: 312.5; 39; 19.5; 39; 156; and 78 micrograms/mL respectively) and compounds 5c and 5h against S. flexneri (MIC: both 312.5 micrograms/mL). The minimal inhibitory concentrations of these compounds were determined using the micro dilution method.     

Synthesis and antimicrobial activity of some 1,2,4-triazole-3-mercaptoacetic acid derivatives

Ethyl 5-(2-furyl)-4-ethyl-1,2,4-triazole-3-mercaptoacetate (2), 5-(2-furyl)-4-ethyl-1,2,4-triazole-3-mercaptoacetic acid hydrazide (3) and a series of new N-alkylidene/arylidene-5-(2-furyl)-4-ethyl-1,2,4-triazole-3-mercaptoacetic acid hydrazides (4a-f) were synthesized and evaluated for in vitro antibacterial activity against Staphylococcus aureus ATCC 6538. Staphylococcus epidermidis ATCC 12228, Klebsiella pneumoniae ATCC 4352, Pseudomonas aeruginosa ATCC 1539, Escherichia coli ATCC 8739, Shigella flexneri, Salmonella typhi, Proteus mirabilis and antifungal activity against Candida albicans ATCC 10231 using the disk diffusion and microdilution methods. Compound 4f showed antibacterial activity against some bacteria. The in vitro antimycobacterial activity of the new compounds against Mycobacterium tuberculosis H37Rv was evaluated employing the BACTEC 460 radiometric system. The highest inhibition observed was 61% at > 6.25 microg/ml.     

Antibacterial diterpenes from the roots of Salvia viridis

Three new diterpenes, salviviridinol, viridinol, viridone, five known diterpenes, sugiol, 1-oxoferruginol, ferruginol, aethiopinone and microstegiol, abietane and rearranged abietane diterpenes were isolated from the roots of Salvia viridis. These compounds were assayed against S. aureus ATCC 6538 P, E. coli ATCC 8739, P. mirabilis ATCC 14153, K. pneumonia ATCC 4352, P. aeruginosa ATCC 27853, S. epidermidis ATCC 12228, E. faecalis ATCC 29212 and a yeast C. albicans ATCC 10231. 1-Oxoferruginol showed activity against B. subtilis, S. aureus, S. epidermidis and a modest activity against P. mirabilis, migrostegiol had a little activity against B. subtilis. The structures of the compounds were established by 1D and 2D NMR spectroscopic techniques.     

α-Helical domain is essential for antimicrobial activity of high mobility group nucleosomal binding domain 2 （HMGN2）

AIM: To examine the antimicrobial spectrum and functional structure of high mobility group nucleosomal binding domain 2 (HMGN2). METHODS: OMIGA protein structure software was used to analyze the two-dimensional structure of HMGN2. Synthetic short peptides were generated for studying the relationship between function and structure. Prokaryotic expression vectors were constructed for the holo-HMGN2 and its helical domain. Their E coli-based products were also prepared for antimicrobial testing. The antimicrobial assay included minimal effective concentration, minimal inhibitory concentration, and minimal bactericidal concentration. RESULTS: OMIGA protein structure software analysis revealed a transmembrane alpha-helical structure (the putative antimicrobial domain) located from position 18 to 48 of the HMGN2 protein sequence. The antimicrobial assay showed that the MIC of the recombinant holo-HMGN2 against E coli ML-35p (an ampicillin-resistance strain), Pseudomonas aeruginosa ATCC 27853 and Candida albicans ATCC 10231 were 12.5, 25, and 100 mg/L, respectively. Against the same microorganisms, the MIC of the synthetic HMGN2 alpha-helical domain were 12.5, 25, and 100 mg/L, respectively, that is, the same as with the recombinant form of HMGN2. In contrast, recombinant holo-HMGN2 was inactive against Staphylococcus aureus ATCC 25923. The synthetic N-terminal and C-terminal fragments of HMGN2 had no antimicrobial activity against E coli ML-35p, P aeruginosa ATCC 27853 or C albicans ATCC 10231. CONCLUSION: HMGN2 showed potent antimicrobial activity against E coli ML-35p, P aeruginosa ATCC 27853 and, to some extent, against C albicans ATCC 10231, but was inactive against S aureus ATCC 25923 in these assay systems. Itos alpha-helical structure may be essential for the antimicrobial activity of HMGN2.     

Long-chain 3-acyl-4-hydroxycoumarins: structure and antibacterial activity

By reacting 4-hydroxycoumarin with long-chain acyl chlorides, a number of new 3-acyl derivatives were prepared and the relationship was studied between their structures and activities against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, and Propionibacterium acnes ATCC 11827. Antibacterial activity was associated with enolic tautomers of a tricarbonylmethane group bearing a lipophilic side chain (undec-10-enoyl, undec-10-ynoyl, palmitoyl or octadec-9-enoyl). A newly synthesized 2-acyl derivative of 2H-indene-1,3-dione containing the same tricarbonylmethane motif showed a comparable activity.     

Antituberculosis agents VIII. Synthesis and in vitro antimycobacterial activity of alkyl alpha-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-ylthio]acetates

A series of alkyl alpha-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-ylthio]acetic acid esters 6a-e were synthesized and evaluated for in vitro antituberculosis activity against Mycobacterium tuberculosis strain H(37)Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. The antituberculosis data indicated that methyl, propyl, buthyl and benzyl esters showed a significant in vitro antimycobacterium tuberculosis activity (MIC=0.39-0.78 microg/ml) and the ethyl analogue did not show a good activity (MIC>6.25 microg/ml, %inhibition=58). The most active compound of the series was n-propyl alpha-[5-(5-nitro-2-thienyl)-1,3,4-thiadiazole-2-ylthio]acetate (6c) with MIC value of 0.39 microg/ml.     

Synthesis and in-vitro antibacterial activity of 7-(3-aminopyrrolo[3,4-c]pyrazol-5(2H,4H,6H)-yl)-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid derivatives

A series of novel 7-(3-aminopyrrolo[3,4-c]pyrazol-5(2H,4H,6H)-yl)-6-fluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid derivatives was designed, synthesized and characterized by (1)H-NMR, MS and HRMS. These fluoroquinolones were evaluated for their in-vitro antibacterial activity against representative Gram-positive and Gram-negative strains. Generally, all of the target compounds display rather weak potency against the tested Gram-negative strains, but most of them exhibit good potency in inhibiting the growth of S. aureus including methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis including methicillin-resistant S. epidermidis (MRSE) (MIC: 0.125-8 μg/mL). In particular, the compound 9g is 2 to 32 fold more potent than gemifloxacin (GM), moxifloxacin (MX), gatifloxacin (GT), and levofloxacin (LV) against S. pneumoniae 08-3, K. pneumoniae 09-23, and P. aeruginosa ATCC27853, 4 to 32 fold more potent than MX, GM, and LV against K. pneumoniae 09-21, and more active than or comparable to the four reference drugs against P. aeruginosa 09-32.     

Synthesis and antituberculosis activity of cycloalkylidenehydrazide and 4-aza-1-thiaspiro[4.5]decan-3-one derivatives of imidazo[2,1-b]thiazole

New N2-cycloalkylidene-(6-phenyl/4-chlorophenylimidazo[2,1-b]thiazol-3-yl) acetic acid hydrazides (2a-h and 3a-b) were synthesized by reacting (6-phenyl/4-chlorophenylimidazo[2,1-b]thiazol-3-yl)acetic acid hydrazides with cyclohexanones or cyclopentanone. Furthermore, 2a-h were refluxed with thioglycolic or thiolactic acid to give 4-[[(6-phenyl/4-chlorophenylimidazo[2,1-b]thiazol-3-yl) acetyl]amino]-4-aza-1-thiaspiro[4.5]decan-3-ones (4a-h and 5a-h). The structures of the title compounds were established by spectral data (IR, 1H-NMR, 13C-NMR and EIMS (Electron Impact Mass Spectrometry)) and elemental analysis. The synthesized compounds were evaluated for antituberculosis activity against Mycobacterium tuberculosis H37Rv (ATCC 27294). The compounds exhibited varying degrees of inhibition in the in vitro primary screening that was conducted at a concentration of 6.25 micrograms/ml against M. tuberculosis H37Rv (ATCC 27294) in Bactec 12B medium using the Bactec 460 radiometric system or a broth microdilution assay, the Microplate Alamar Blue Assay (MABA). Compounds 2f, 2h, 3b, 4a, 4c, 4d, 5a-e and 5h demonstrating at 1-east 90% inhibition in the primary screen were re-tested at lower concentrations against M. tuberculosis H37Rv (ATCC 27294) to determine the actual minimum inhibitory concentration (MIC) using MABA. The most active compounds were found to be 4d and 5c. The structure-activity relationships of the derivatives were investigated.     

Synthesis and antituberculosis activity of new hydrazide derivatives

The increasing clinical importance of drug-resistant mycobacterial pathogens, especially Mycobacterium tuberculosis, has lent additional urgency to microbiological research and new antimycobacterial compound development. For this purpose, new hydrazide derivatives of imidazo[1,2-a]pyridine were synthesized and evaluated for antituberculosis activity. The reaction of 2-[(2-carboxyimidazo[1,2-a]pyridine-3-yl)sulfanyl]acetic acid hydrazide with various benzaldehydes gave N-(arylidene)-2-[(2-carboxyimidazo[1,2-a]pyridine-3-yl)sulfanyl]acetic acid hydrazide derivatives. The chemical structures of the compounds were elucidated by IR,(1)H-NMR, FAB-MS spectral data and elemental analysis. Antituberculosis activities of the synthesized compounds were determined by broth microdilution assay, the Microplate Alamar Blue Assay in BACTEC 12B medium. The results were screened in vitro, using the BACTEC 460 Radiometric System against Mycobacterium tuberculosis H37Rv (ATCC 27294) at 6.25 microg/mL; the tested compounds showed significant inhibition.     

Synthesis and potent antimicrobial activity of some novel 4-(5, 6-dichloro-1H-benzimidazol-2-yl)-N-substituted benzamides

A series of 4-(5, 6-dichloro-1H-benzimidazol-2-yl)-N-substituted benzamides were synthesized and evaluated for antibacterial and antifungal activities against Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), methicillin-resistant S. epidermis (MRSE), Enterococcus faecalis, Escherichia coli and Candida albicans. Certain compounds inhibit bacterial growth with low MIC values (microg/mL). Among them, compounds 10 and 11 exhibited the greatest antibacterial activity with MIC values of 3.12 microg/mL against S. aureus, MRSA and MRSE.     

Synthesis and antimicrobial activity of some 5-[2-(morpholin-4-yl)acetamido] and/or 5-[2-(4-substituted piperazin-1-yl)acetamido]-2-(p-substituted phenyl)benzoxazoles

In this study, a series of twelve novel 5-[2-(morpholin-4-yl)acetamido] and/or 5-[2-(4-substituted pip-erazine-1-yl)acetamido]-2-(p-substituted phenyl]benzoxazole derivatives have been synthesized and their structures were confirmed by IR, (1)H NMR, and mass spectral data. These compounds were prepared by reacting 5-(2-chloroacetamido)-2-(4-p-substituted-phenyl)benzoxazoles, which were obtained by using 5-amino-2-[p-substituted-phenyl]benzoxazoles with chloroacetyl chloride, in the presence of morpholine or 1-substituted piperazines. All synthesized compounds 3-14 were tested by using the method of twofold serial dilution technique for in vitro activities against certain strains of Gram-positive, Gram-negative bacteria as well as the yeasts Candida albicans, Candida krusei, and Candida glabrata in comparison with standard drugs. Microbiological results showed that the newly synthesized compounds possessed a broad spectrum of activity, showing MIC values of 3.12-50 mug/mL against the Candida species.     

Antimicrobial Activity of Some Lactarius Species

The extracts obtained from six Lactarius species [Lactarius deterrimus Grager, Lactarius sanguifluus (Paul.: Fr.) Fr., Lactarius semisanguifluus Heim et Leclair, Lactarius piperatus Scop. ex Fr., Lactarius deliciosus (L. ex Fr.) S.F. Gray and Lactarius salmonicolor Heim et Leclair] have been investigated for their antimicrobial activity. Growth inhibition using agar disk diffusion assays was determined against: Escherichia coli ATCC 11230, Micrococcus luteus ATCC 2971, Stapylococcus aureus ATCC 6538P, Salmonella thyphi ATCC 19430, Klebsiella pneumoniae UC57, Pseudomonas aeruginosa ATCC 27853, Corynebacterium xerosis CCM 2824, Bacillus cereus ATCC 7064, Bacillus megaterium DSM 32, Mycobacterium smegmatis CCM 2067, Candida albicans ATCC10231 and Saccharomyces cerevisiae ATCC 9763. As a result of this study, we have found that Lactarius species revealed antimicrobial activity against some Gram (+) and Gram (-) bacteria, but showed no antagonistic effect against yeasts used in this study.     

Antimicrobial Activity of Three Endemic Verbascum Species

The extracts obtained from three Verbascum L. species (Verbascum olympicum Boiss., Verbascum prusianum Boiss., and Verbascum bombyciferum Boiss.) have been investigated for their antimicrobial activity. Growth inhibition, using the agar disc diffusion assay, was determined against Escherichia coli ATCC 11230, Micrococcus luteus La 2971, Staphylococcus aureus ATCC 6538P, Salmonella thyphi ATCC 19430, Klebsiella pneumoniae UC57, Pseudomonas aeroginosa ATCC 27893, Corynebacterium xerosis CCM 2824, Bacillus cereus ATCC 7064, Bacillus megaterium DSM 32, Mycobacterium smegmatis CCM 2067, Proteus vulgaris ATCC 8427, Candida albicans ATCC 10231, Rhodotorula rubra, and Saccharomyces cerevisiae ATCC 9763. We found that Verbascum L. species showed antimicrobial activity against the Gr(+) bacteria and yeasts, but no activity was seen against the Gr(-) bacteria used in this study.     

Synthesis and antimicrobial activity of new 2-[p-substituted-benzyl]-5-[substituted-carbonylamino]benzoxazoles

A series of 23 new 2-[p-substituted-benzyl]-5-[p-substituted-phenyl/benzyl-carbonylamino]benzoxazole derivatives has been synthesized by reacting 5-amino-2-[p-substituted-benzyl]benzoxazoles with the appropriate carboxylic acid chlorides. The structures of the synthesized compounds were confirmed by IR and (1)H-NMR spectral data. Antimicrobial activities of the compounds were investigated using the twofold serial dilution technique against two gram-positive and two gram-negative bacteria and three Candida species in comparison with standard drugs. Microbiological results indicated that the newly synthesized 2-[p-substituted-benzyl]-5-[p-substituted-phenyl/benzyl-carbonylamino]benzoxazole derivatives (3-25) possessed a broad spectrum of activity, showing MIC values of 6.25-200 microg/mL against the gram-positive and gram-negative microorganisms tested. Moreover, they showed significant antifungal activity with MIC values of 3.12-100 microg/mL against the Candida species tested. Especially, with a MIC value of 3.12 microg/mL, 2-benzyl-5-[p-bromobenzyl-carbonylamino]benzoxazole 9 displayed the same activity against C. glabrata as the standard drug myconazol.     

Synthesis and antimicrobial activity of 3-(4'-hydroxy-3'-methylphenyl)-5-[(substuted) phenyl]-4,5-dihydro-1H-1-pyrazolyl-4-pyridylmethanone derivatives

A series of 3-(4'-hydroxy-3'-methylphenyl)-5-[(substituted) phenyl]-4,5-dihydro-1H-1-pyrazolyl-4-pyridylmethanone derivatives were synthesized by the reaction between isoniazid (INH) and various chalcones and were tested for their antimicrobial activity in vitro against Staphylococcus aureus 209p, Escherichia coli ESS 2231, Aspergillus fumigatus, Candida albicans, Candida albicans ATCC 10231, Candida krusei GO3 and Candida glabrata HO5. Among the synthesized compounds, all the compounds possess the significant antibacterial activity. Compounds I(III) and I(x), i.e. 3-(4'-hydroxy-3'-methylphenyl)-5-(4"-dimethylaminophenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyridyl methanone and 3-(4'-hydroxy-3'-methylphenyl)-5-(2",6"-dichlorophenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyridylmethanone were found to be the most active agents against used bacterial and fungal strains with minimum inhibitory concentration of less than 0.5 microg/mL and were equally active as standard drugs Ofloxacin and Fluconazole.     

7-{4-［2-［2-取代-4-((5S)-5-乙酰胺甲基-2-氧代-噁唑烷-3-基)苯基］乙基］哌嗪-1-基}-氟喹诺酮类化合物的合成与抗菌活性

目的寻找新型的噁唑烷酮-氟喹诺酮类抗菌药物。方法设计合成了7-{4-［2-［2-取代-4-((5S)-5-乙酰胺甲基-2-氧代-噁唑烷-3-基)苯基］乙基］哌嗪-1-基}-氟喹诺酮类化合物，测定其体外抗菌活性。结果共合成20个目标化合物，经^{1H NMR和MS确证结构。目标化合物具有较好的体外抗菌活性，尤其是化合物22，对屎肠球菌的抑制活性分别是吗啉噁酮和诺氟沙星的16倍和64倍，对金葡菌的抑制活性为吗啉噁酮的4倍。结论某些带有氟喹诺酮结构片段的噁唑烷酮类化合物抗菌活性加强。}