Synthesis and antibacterial activity of new cephalosporins with lactonyloxyimino moiety

A series of 7-{2-(2-aminothiazol-4-yl)-2-Z-(γ-lacton-3-yl) oxyiminoacetamidol} cephalosporins with various substituents at the 3-position in cephem nucleus were synthesized and evaluated microbiologically. The tested compounds showed potent activities but were somewhat less active than cefotaxime or cefixime against a wide variety of Gram-positive and Gram-negative bacteria.     

Synthesis and antibacterial activities of new bis-benzimidazoles

Twenty bis-benzimidazole derivatives were synthesised by the reaction of benzimidazole with appropriate alkyl halides. The compounds synthesised were identified by 1H, 13C-NMR, FT-IR and micro analysis. All compounds studied in this work were screened for their in vitro antibacterial activity against standard strains; Enterococcus faecalis (ATCC 29212), Staphylococcus aureus (ATCC 29213), Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853). Ten of the compounds were found effective to inhibit the growth of gram-positive bacteria (E. faecalis and S. aureus) at MIC (minimal inhibitory concentration) values between 50-400 microg/ ml. Two of the compounds showed MIC values of 200 microg/ml against gram-negative bacteria (E. coli and P. aeruginosa).     

大环内酯类衍生物的合成及其体外抗菌活性

目的研究大环内酯类抗生素衍生物的合成及其抗菌活性.方法以红霉素为起始原料,经过肟化、重排和胺化反应合成目标化合物;测定目标化合物的抗菌活性.结果与结论设计、合成了10个红霉素衍生物(YAM-1～YAM-10),所有化合物经质谱和核磁共振碳谱确证均为新化合物.化合物YAM-9的活性与红霉素相同,该化合物值得进一步研究.     

噁唑烷酮类化合物的合成及抗菌活性

目的设计合成(口恶)唑烷酮类化合物,并对其体外抗菌活性进行初步评价.方法 以3,4-二氟硝基苯为原料,经多步反应合成目标化合物;采用微量液体稀释法,检测目标化合物对金黄色葡萄球菌和表皮葡萄球菌的抑制和杀灭作用.结果与结论 合成了10个新化合物,经1H-NMR、MS确证其结构.体外试验表明:化合物7f的体外抗菌活性与对照药物利奈唑酮相当,化合物7a、8c和8d表现出一定的抗菌活性.     

酰基内酯类红霉素衍生物的合成及体外抗菌活性

目的研究大环内酯类酰内酯(acylide)衍生物的合成并评价其体外抗菌活性.方法以克拉霉素为起始原料,经4步反应合成目标化合物;采用对倍稀释法测定目标物的抗菌活性.结果与结论合成了9个酰内酯衍生物,均未见文献报道,并经质谱和核磁共振碳谱确证.抗菌活性实验显示:化合物XNZ-1的活性较好.     

Synthesis and antibacterial activities of new 3-phenoxymethylcephalosporins.

The synthesis and biological properties of new 3-phenoxymethylcephalosporins (1) are described. These compounds exhibited good antibacterial activity against Gram-positive and Gram-negative bacteria.     

新型噁唑烷酮-吲哚羧酸酯杂合物的合成及抗菌活性

摘 要：目的 设计并合成一类新型的4-哌嗪苯基噁唑烷酮-吲哚羧酸酯杂合物，初步评价其体外抗菌活性。方法 以(S)-N-[[3-[3-氟-4-(哌嗪-1-基)苯基]-2-氧代-5-噁唑烷酮基]甲基]乙酰胺为起始原料，经过2步反应合成目标化合物；采用微量液体稀释法，测定目标化合物的体外抗菌活性。结果与结论 合成了14个新化合物，其结构经1H-NMR和MS确认，7个化合物显示出不同程度的抗菌活性，化合物3a和4b的活性突出，可进行深入研究。     

新型唑烷酮类化合物的全合成及抗菌活性研究

目的设计合成     

新型(口恶)唑烷酮类化合物的全合成及抗菌活性研究

目的设计合成(口恶)唑烷酮类化合物,初步评价其体外抗菌活性.方法以间氟苯胺为起始原料,设计合成了10个目标化合物;采用微量液体稀释法,检测目标化合物对金黄色葡萄球菌和表皮葡萄球菌的抑制和杀灭作用.结果与结论所有化合物均未见文献报道,其结构经1H-NMR、MS确认.体外试验表明:化合物Ⅱa的体外抗菌活性与利奈唑酮相当,化合物Ⅱb、Ⅱc和Ⅱd表现出一定的抗菌活性.     

新3,5-二取代噁唑烷酮抗菌剂的合成及其体外抑菌活性

目的设计、合成噁唑烷酮新化合物并测定其体外抑菌活性.方法对文献方法进行了改进,在文献报道的构效关系基础上,设计、合成噁唑烷酮新化合物并测定体外抑菌活性.结果合成了39个新化合物,其中目标物18个,其结构经IR,1HNMR,MS等方法确证.16个化合物显示出较好的抑菌活性,其中化合物9,10,10b对4种试验菌的MIC50和 MIC90值小于或接近4种对照药,化合物9a和11c没有抑菌活性.结论化合物9,10和10b值得进一步研究.     

Synthesis and preliminary antimicrobial evaluation of new 7-(N-pyrrolyl) derivatives of cephalosporins

A series of seven new cephalosporins was prepared for preliminary microbiological evaluation by N-acylation of 7-aminocephalosporanic acid with substituted N-pyrrolylcarboxylic acids via mixed anhydrides. The chemical structure of the compounds were confirmed by IR, 1H-NMR and mass spectral data. The 7-(N-pyrrolyl) cephalosporin derivatives were tested in vitro by the disc diffusion method upon 3 strains and subsequent determination of the minimal inhibitory concentration (MIC) of the most active ones upon 29 strains. The products of the series exhibited antibacterial activity. They showed selective potency against gram-positive and were practically inactive against gram-negative microorganisms. The compound 3-[(acetyloxy)methyl]-7-([2-[3-(ethoxycarbonyl)-2-methyl-5-phenyl-1H-1-pyrrolyl]acetyl]amino)-6-oxo-7,7a-dihydro-2H,6H-aceto[2,1-b][1,3]thiazine-4-carboxylic acid (4a) was outlined as more active than the reference cefazolin (CAS 23325-78-2) in regard to S. pyogenes and some strains of S. aureus, the MIC of 4a against S. pyogenes were at least 4-fold lower. The toxicological evaluations of the starting N-pyrrolylcarboxylic acids showed no acute toxicity.     

Studies on condensed-heterocyclic azolium cephalosporins. V. Synthesis and antibacterial activity of 3-(condensed-triazolo-pyridinium, -pyrimidinium, and -pyridazinium)-methyl cephalosporins.

As a part of our studies on cephalosporins bearing condensed-heterocyclic azolium methyl groups at the 3 position in the cephalosporin nucleus, we describe here the synthesis and antibacterial activity of 7 beta-[2-(2-aminothiazol-4-yl)2(Z)-methoxyiminoacetamido] cephalosporins (1-16, 7 beta-[2-(2-amino-5-chlorothiazol-4-yl)-2(Z)- methoxyiminoacetamido] cephalosporins (17,18) and 7 beta-[2-(5-amino- 1,2,4-thiadiazol-3-yl)-2(Z)-methoxyiminoacetamido) cephalosporins (19-23) containing a variety of condensed-heterocyclic triazolium methyl groups at the 3 position in the cephalosporin nucleus. These cephalosporins exhibited potent antibacterial activity, and it appears that condensed-heterocyclic triazolium as well as condensed-heterocyclic imidazolium rings are effective moieties for improving antibacterial activity and the spectrum of activity. Among the cephalosporins tested, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3-(5- methyl[1,2,3]triazolo-[1,5-alpha]pyridinium-1-yl)methyl-3-cephem-4- carboxylate (9) and 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3-(6- methoxy[1,2,4]triazolo[1,5-alpha]pyridinium-1-yl)methyl-3-cephem-4- carboxylate (11) showed good antibacterial activity.     

Synthesis and antibacterial activity of C-3' isothiazolyl and related cephalosporins

The synthesis of C-3' isothiazolyl and related cephalosporins is presented. The compounds exhibit activity against a variety of Gram-positive and Gram-negative organisms.     

新3,5-二取代唑烷酮抗菌剂的合成及其体外抑菌活性新3,5-二取代唑烷酮抗菌剂的合成及其体外抑菌活性

目的设计、合成唑烷酮新化合物并测定其体外抑菌活性。方法对文献方法进行了改进，在文献报道的构效关系基础上，设计、合成唑烷酮新化合物并测定体外抑菌活性。结果合成了39个新化合物，其中目标物18个，其结构经IR,¹HNMR,MS等方法确证。16个化合物显示出较好的抑菌活性，其中化合物9，10，10b对4种试验菌的MIC50和 MIC90值小于或接近4种对照药，化合物9a和11c没有抑菌活性。结论化合物9，10和10b值得进一步研究。