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1.
In order to improve the antibacterial activity of cefozopran (CZOP) against methicillin-resistant Staphylococcus aureus (MRSA), we initiated chemical modification to introduce a 2-(5-amino-1,2,4-thiadiazol-3-yl)-2(Z)-hydroxyimino acetyl group at the C-7 position and a 3- or 6-substituted imidazo[1,2-b]pyridazinium or 5-substituted imidazo[1,2-a]pyridinium group at the C-3' position. Although this approach successfully enhanced the anti-MRSA activity of CZOP two to eight times, a slight decrease in the activity against Gram-negative bacteria including Pseudomonas aeruginosa was involved. Among the novel derivatives, 3-(6-aminoimidazo[1,2-b]pyridazinium-1-yl)methyl-7beta-[2-(5-amino-1,2,4-thiadiazol-3-yl)-2(Z)hydroxyiminoacetamido]-3-cephem-4-carboxylate (44a) showed an excellent balance of activity against MRSA and Gram-negative bacteria. 相似文献
2.
Ishikawa T Kamiyama K Matsunaga N Tawada H Iizawa Y Okonogi K Miyake A 《The Journal of antibiotics》2000,53(10):1071-1085
In an effort to discover a novel cefozopran (CZOP) derivative having excellent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), we performed chemical modification of the alkoxyimino moiety and imidazo[1,2-b]pyridazinium group of CZOP. Among the prepared compounds, the cyclopentyloxyimino derivative 7beta-[2-(5-amino-1,2,4-thiadiazol-3-yl)-2(Z)-cyclopentyloxyiminoacetamido]-3-(3,6-diaminoimidazo[1,2-b]pyridazinium-1-yl)methyl-3-cephem-4-carboxylate (20 g) showed the most potent anti-MRSA activity, reflecting its high affinity (IC50 = 1.6 microg/ml) for penicillin binding protein 2' (PBP2'), although its anti-MRSA activity was slightly inferior to that of vancomycin (VCM). In experimental systemic infection in mice, however, 20 g showed activity comparable to that of VCM against MRSA. In addition, 20 g showed activity similar or slightly inferior to that of CZOP against Pseudomonas aeruginosa both in vitro and in vivo. Considering its favorable antibacterial activity profile, 20 g was considered to be the most promising CZOP derivative for further studies. 相似文献
3.
A Miyake Y Yoshimura M Yamaoka T Nishimura N Hashimoto A Imada 《The Journal of antibiotics》1992,45(5):709-720
The synthesis and in vitro antibacterial activity of 7 beta-[2-(5-amino-1,2,4-thiadiazol-3-yl)-2(Z)-alkoxyiminoacetami do] cephalosporins bearing various condensed-heterocyclic azolium groups at the 3 position in the cephalosporin nucleus are described. The thiadiazolyl cephalosporins showed good antibacterial activity against both Gram-positive and Gram-negative bacteria and the MICs of the thiadiazolyl cephalosporins against Pseudomonas aeruginosa was more potent than that of the corresponding 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-alkoxyiminoacetamido]-3- (condensed-heterocyclic azolium)methyl cephalosporins. Also, the thiadiazolyl cephalosporins bearing (imidazo[1,2-b]-pyridazinium-1-yl)methyl groups at the 3 position showed antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Among the cephalosporins tested, 7 beta-[2-(5- amino-1,2,4-thiadiazol-3-yl)-2(Z)-methoxyiminoacetamido]-3-(imidaz o[1,2- b]pyridazinium-1-yl)methyl-3- cephem-4-carboxylate (4, SCE-2787) which exhibited the most potent antibacterial activity and the broadest antibacterial spectrum was selected as a parenteral cephalosporin candidate for further biological evaluation. 相似文献
4.
As a part of our research on the synthesis of cephalosporins bearing condensed-heterocyclic azolium groups at the 3 position in the cephalosporin nucleus, we describe herein the synthesis of 7 beta-[2-(2-amino-5-halogeno-, methylthio-, methylsulfinyl-, methylsulfonyl- and sulfothiazol-4-yl)-2(Z)-alkoxyiminoacetamido] cephalosporins and their antibacterial activity. Among the compounds prepared, 7 beta-[2-(2-amino-5-chlorothiazol-4-yl)-2(Z)- methoxyiminoacetamido]-3-(imidazo[1,5-a]-pyridinium-1-yl)methyl-3-cephem -4-carboxylate (14) showed good antibacterial activity against both Staphylococcus aureus including methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, whereas the antibacterial activity against other Gram-negative bacteria was a slightly lower than that of 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3-(im ida zo [1,2-a]pyridinium (I-1) and imidazo[1,5-a]pyridinium (I-4)-1-yl)methyl-3-cephem-4-carboxylates. 相似文献
5.
The synthesis, antibacterial activity and oral absorption in rats of new 7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(carboxymethoxyimino)ace tamido] cephalosporins (1) having various substituted-alkylthio groups at the C-3 position of the cephem nucleus are described. Of these, the cephalosporins with a cyanomethylthio group (1d) and fluoroethylthio group (1p) at the C-3 position showed a potent in vitro antibacterial activity against Gram-positive and Gram-negative bacteria as well as good oral absorption in rats. When administered orally to mice infected with Klebsiella pneumoniae, 1d had stronger protective effect than 1p. The structure-activity relationships of 1 are also presented. 相似文献
6.
Y Yoshimura A Miyake T Nishimura T Kawai M Yamaoka 《The Journal of antibiotics》1991,44(12):1394-1405
From our series of 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)-alkoxyiminoacetamido]ceph alosporins containing imidazo[1,5-a]pyridinium, imidazo[1,2-b]pyridazinium, imidazo[1,2-a]pyrimidinium, imidazo[1,2-c]pyrimidinium, and pyrazolo[1,5-a]pyridinium methyl groups at the 3 position. Among the cephalosporins tested, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3- (imidazo[1,5-a]pyridinium-2-yl) (1), (imidazo[1,2-b]pyridazinium-1-yl) (2), and (pyrazolo[1,5-a]-pyridinium-1-yl) (3)methyl-3-cephem-4-carboxylates showed potent antibacterial activity and broad antibacterial spectrum. The antibacterial activity of these cephalosporins (1 approximately 3) was superior to that of ceftazidime (CAZ). These results imply that the delocalization of the positive charge of the imidazo[1,5-a]pyridinium, pyrazolo[1,5-a]pyridinium and imidazo[1,2-b]pyridazinium groups leads to an expanded antibacterial spectrum and increased activity and that these condensed-heterocyclic compounds as well as imidazo[1,2-a]pyridine are effective moieties for improving antibacterial activity and spectrum. 相似文献
7.
M Arimoto T Hayano T Soga T Yoshioka H Tagawa M Furukawa 《The Journal of antibiotics》1986,39(9):1243-1256
Syntheses of cephalosporins modified with a 7 beta-[2-(2-aminothiazol-4-yl)-2-(substituted carbamoylmethoxyimino)acetamido] group at the C-7 position and with various hetero aromatics at the C-3 position are described. The effects of substituents on the carbamoyl group in the 7-side chain were investigated in order to improve antibacterial activity. Some of these compounds exhibited high antibacterial activity against Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa, as well as good resistance to beta-lactamase. 相似文献
8.
T Nishimura Y Yoshimura M Yamaoka T Kawai A Miyake 《The Journal of antibiotics》1991,44(12):1371-1393
In our study of the structure-activity relationships of cephalosporins bearing quaternary ammonium groups at the 3 position, we postulated that delocalization of the azolium positive charge would lead to an expanded antibacterial spectrum and increased activity. Since quaternization of condensed-heterocyclic compounds such as imidazo[1,2-a]pyridine gives positive charge delocalization, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-alkoxyiminoacetamido] cephalosporin derivatives (1-53) bearing various (imidazo[1,2-a]pyridinium-1-yl)methyl moieties at the 3 position were prepared and their antibacterial activity was determined. As expected, these cephalosporins exhibited potent activity against both Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa. These results imply that imidazo[1,2-a]pyridine is a quite useful substituent for improving antibacterial activity and spectrum. The structure-activity studies revealed that a favorable substituent on the imidazo[1,2-a]pyridine is the cyano radical at the 6 position of the ring, and ethoxyimino or 1-carboxy-1-methylethoxyimino groups are suitable for the alkoxyimino substituent. Among the cephalosporins tested, 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)- ethoxyiminoacetamido]-3-(6-cyanoimidazo[1,2-a]pyridinium -1-yl)methyl-3-cephem-4-carboxylate (45) and 7 beta-[2-(2-aminothiazol-4-yl)-2(Z)-(1- carboxy-1-methylethoxyiminoacetamido]-3-(6-cyanoimidazo[1,2- a] pyridinium-1-yl)methyl-3-cephem-4-carboxylate (49) showed good antibacterial activity. 相似文献
9.
K Sakagami T Watanabe S Fukatsu H Nitta M Hatanaka T Ishimaru 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1989,109(12):913-925
3-Alkylthio-7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(O-substituted oxyimino)acetamido]cephalosporins (6 and 7) and the 3-methoxy analogues (10) were prepared by coupling diphenylmethyl 7-amino-3-alkylthio-3-cephem-4-carboxylate (1 and 2) or diphenylmethyl 7-amino-3-methoxy-3-cephem-4-carboxylate with (Z)-2-(2-tritylaminothiazol-4-yl)-2-(O-substituted oxyimino)acetic acid (4), followed by deprotection and subjected to examination of antibacterial activities. The pivaloyloxymethyl esters (8 and 9) of the compounds (6 and 7) were also prepared and oral activities of these esters were compared with those of the parent compounds (6 and 7). The cephalosporins (6a-j and 7a-c) had potent and wide antibacterial spectra against Gram positive and Gram negative bacteria which were comparable to those of cefixime or cefteram. Among them, the cephalosporins (6f and 7c) and the pivaloyloxymethyl esters (8b and 9b) had good in vivo efficacy in mice against infections of Escherichia coli No. 29 and especially 8b showed high urinary recovery in mice. 相似文献
10.
2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酸S-苯并噻唑硫酯的合成 总被引:1,自引:0,他引:1
2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酰胺与2-巯基苯并噻唑为原料,哌啶为溶剂,在三乙胺催化下反应制得头孢菌素中间体2-(5-氨基-1,2,4-噻二唑-3-基)-2-(Z)-甲氧亚氨基乙酸S-苯并噻唑硫酯,收率约76%。 相似文献
11.
C Yokoo M Goi A Onodera M Murata T Nagate Y Watanabe K Sota 《The Journal of antibiotics》1988,41(2):181-192
The synthesis, antibacterial activity and oral absorption in rats of 3-alkoxycarbonyl-methoxy-7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(O-substituted oxyimino)acetamido]cephalosporins (1) are described. In this cephalosporin series, 7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(carboxy-methoxyimino)acetamid o] cephalosporins (1b, 1i and 1j) with a lower alkoxycarbonylmethoxy group at the C-3 position of a cephem nucleus exhibited not only potent activity against Gram-negative bacteria but also good oral absorption in rats. Structure-activity relationships of 1 are also presented. 相似文献
12.
Cephalosporin derivatives (I) substituted with a neutral, acidic or basic amino acid group as the terminal group attached to the 2-amino-2-(2-aminothiazol-4-yl)acetamido side chain at the C-7 position were synthesized, and the effect of each group on antibacterial activity was examined. The derivatives bearing an amidino or guanidino group showed broad spectra of antibacterial activity similar to those of cefotaxime, but they were relatively sensitive to beta-lactamases. 相似文献
13.
目的 合成头孢唑兰中间体(Z)-2-(5-氨基-1,2,4-噻二唑-3-基)-2-甲氧亚氨基乙酸。方法 以氰乙酰胺为起始原料,依次经甲氧亚氨化、加成、酯化、与硫氰化钾反应、构型转换和水解共6步反应制得目标化合物。结果和结论 目标化合物的结构经1H-NMR和MS谱确证。该工艺路线原料易得,操作简便,总收率为29.8%,具有一定的工业化价值。 相似文献
14.
A series of new 7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(carboxymethoxyimino)ace tamido] cephalosporins (1) having various substituted-vinylthio groups at the C-3 position of the cephen nucleus was synthesized and evaluated for antibacterial activity and oral absorption in rats in comparison with cefixime. Of these, the cephalosporins (1a and 1c) with a lower alkoxycarbonylvinylthio group (Z-form) at the C-3 position showed a potent antibacterial activity against Gram-negative bacteria, improved activity against Staphylococcus aureus as well as good oral absorption in rats. The structure-activity relationships of 1 are also presented. 相似文献
15.
16.
A series of new 3-[(Z)-2-methoxycarbonylvinylthio]-7 beta-[(2- aminothiazol-4-yl)acetamido]-cephalosporins (1) having various oxyimino groups (Z-form) at the alpha position of the C-7 side chain was synthesized and evaluated for antibacterial activity and oral absorption in rats. Of these, the cephalosporin (1a) with a hydroxyimino group in the C-7 side chain showed a potent antibacterial activity against Gram-negative bacteria and Gram-positive Staphylococcus aureus as well as good oral absorption in rats. The structure-activity relationships of 1 are also presented. 相似文献
17.
W J Wheeler J B Deeter D R Finley M D Kinnick R Koehler H E Obsorne J T Ott J K Swartzendruber D G Wishka 《The Journal of antibiotics》1986,39(1):111-120
A series of 7 beta-[2-(5-aminooxadiazol-3-yl)-2-Z-methoximinoacetamido] -3-cephem-4-carboxylic acids (7a-g) were synthesized and evaluated microbiologically Although somewhat less active than cefotaxime 7a-g showed good antimicrobial activity against a wide variety of Gram-positive and Gram-negative bacteria. The beta-lactamase stability of 7a and 7f was also discussed. 相似文献
18.
(Z)-2-(5-氨基-1,2,4-噻二唑-3-基)-2-甲氧亚氨基乙酸合成路线图解 总被引:3,自引:0,他引:3
(Z)-2-(5-氨基-1,2,4-噻二唑-3-基)-2-甲氧亚氨基乙酸(1)是合成头孢唑兰(cefozopran)和头孢克定(cefclidin)㈨等头孢菌素的关键中间体。1的合成路线按噻二唑环形成前或后引入甲氧亚氨基可分为两类,现分述如下: 相似文献
19.
A series of new 7 beta-[(Z)-2-(2-aminothiazol-4-yl)-2-(hydroxyimino)acetamido] cephalosporins (1) having various substituted alkylthio groups at the C-3 position of the cephem nucleus were prepared and evaluated for antibacterial activity and oral absorption in rats. Of these, the cephalosporin with a cyanomethylthio group (1a) showed the greatest activity against Staphylococcus aureus and Gram-negative bacteria. Its pivaloyloxymethyl ester (6a), a representative prodrug, exhibited good in vivo efficacy in mice by oral administration. The structure-activity relationships of 1 are also presented. 相似文献
20.
K Sakagami K Atsumi T Yoshida K Nishihata 《Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan》1989,109(6):377-387
Synthesis and antibacterial activity of 7-[2-(2-aminothiazol-4-yl)-3-carboxy-2-propenoamido]cepha los porins and their derivatives are described. These compounds are of interest as carbon analogues of oximecephalosporins, 7-[2-(2-aminothiazol-4-yl)-2(Z)-oxyiminoacetamido]cephalo spo rins having remarkable antibacterial activity. The synthesized 7-[2-(2-aminothiazol-4-yl)-3(Z)-carboxy-2-propenoamido]-c eph alosporins (14, 19) show improved activity especially against the beta-lactamase-producing strains. A 7-[2-(2-aminothiazol-4-yl) maleimido]cephalosporin (15) has been also prepared by cyclization of 7-[3-(2-aminothiazol-4-yl)-2-ethoxycarbonyl-2(Z)-propenoamido++ +]cephalosporin. 相似文献