• 대한화학회지
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• 제33권5호
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• pp.545-550
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• 1989

트리에틸아민 존재하에서 (3R, 4R)-1-(1-벤질옥시카르보닐-2-메틸-1-메틸-프로펜일)-4-메르캅토-3-페닐아세트아미도아제티딘-2-온(8)에 이황화 탄소화 할로겐화 알킬을 반응시켰을 때 ${\beta}$-락탐 고리가 절단된 (Z)- 및 (E)-1-알킬티오-5-벤질옥시카르보닐-6-메틸-2-페닐아세트아미도-4-아자-1,5-헵타디엔-3-온(13-16) 또는 2-벤질-4-(3-벤질옥시카르보닐-4-메틸-1-옥소-2-아자-3-펜텐일)티아졸(17)이 생성되었다.

• Bulletin of the Korean Chemical Society
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• 제31권3호
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• pp.620-623
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• 2010

A brush type chiral stationary phase (CSP 2) derived from ${\alpha}$-amino ${\beta}$-lactam was prepared for the separation of the enantiomers of ${\beta}$-blockers. Compared to the CSP derived from ${\alpha}$-amino phosphonate (CSP 1), in general, the conformationally rigid CSP 2 showed greater scope and much enhanced enantioselectivity for the resolution of ${\beta}$-blockers. The effect of various salt additives on enantioseparation of ${\beta}$-blockers in the mobile phase was investigated. The unusual effect of temperature on the chromatographic behaviors was observed on CSP 2. It also afforded appreciable increases in enantioselectivity without significantly affecting resolution, as the column temperature was reduced.

• 약학회지
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• 제41권4호
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• pp.462-472
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• 1997

In this approach, the antimicrobial activities of the compounds were compared with the ${\beta}$-lactam antibiotics against ${\beta}$-lactamase producing strains in vitro. Heteroc yclyl exomethylenepenam derivatives were several numbers of 6-exomethylenepenam sodiums (CH1240, CH1245, CH1250, CH2140, CH2145, CH2150). The inhibitory concentraion assay of six compounds were compared with clavulanic acid, sulbactam, tazobactam. Clavulanic acid, sulbactam and tazobactam are used as inhibitors of a variety of plasmid-mediated beta-lactamases. In vitro ${\beta}$-lactamase inhibitory assay, CH1240 and CH2140 were more active than clavulanic acid, sulbactam and tazobactam against ${\beta}$-lactamases overally. And in vitro comparative antimicrobial susceptibility test of six inhibitors were performed with mixed forms of ampicillin, cefotaxime, amoxicillin, ticarcillin, piperacillin, cefoperazone against ${\beta}$-lactamase producing 31 species strains. Consequently CH2140 and CH1240 among the six compounds enhanced the activity of the ${\beta}$-lactams for 31 ${\beta}$-lactamase producing strains.

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.456-456
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• 1991

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.457-457
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• 1991

• Bulletin of the Korean Chemical Society
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• 제9권3호
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• pp.189-190
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• 1988

• Applied Biological Chemistry
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• 제40권2호
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• pp.157-162
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• 1997

Cephem계 항생물질의 기본 구조인 7-aminocephalosporanic acid (7-ACA)의 $C_3$ 위치에 thiol기를 도입하고 $C_7$ 위치 aminothiazole기를 결합시킨 신규 화합물(YH-487)에 대한 감염치료효과, 체내동태 그리고 이의 투여에 의한 흰쥐의 장내균총들의 영향에 관하여 검토한 결과, YH-487을 흰쥐에 꼬리정맥을 통하여 20mg/kg으로 투여시 혈중 최고농도 등 체내동태는 제 3세대 ${\beta}-lactam$계 약물인 cefotaxime 등과 유사한 결과를 보였으며 장기조직으로의 이행성은 신장으로의 이행율이 가장 좋았고 배설은 신장 배설 타입이었으며 배설된 약물은 체내의 대사에 의한 변화를 받지 않았다. 또한 YH-487의 대장균 감염증에 대한 치료효과는 cefotaxlme의 3배, cefotiam의 약 20배 정도 높았다. 한편 YH-487의 투여에 의한 흰쥐의 장내 균총의 변화는 Enterobacter와 Bacteroides속 등 Gram 음성 세균은 투여 후 균수가 크게 감소 하였으나 Lactobacillus, Bifidobacterium과 Staphylococcus속 등 Gram 양성 세균은 영향을 받지 않았다. 또한 YH-487을 연속 투여한 후 분리한 균주의 항균활성은 투여전의 균주와 차이가 없어 내성균의 출현 가능성이 낮았다.

• Archives of Pharmacal Research
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• 제15권3호
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• pp.234-238
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• 1992

Using cell-free extract of Lysobacter lactamgenus, enzymatic conversion of $\delta$-L-($\alpha$-aminoadiphyl)-L-cysteinyl-D-valine (ACV) the first substrate of $\beta$-lactam biosynthesis, into antibiotic compounds was attempted. In high performance liquid chromatographic (HPLC) analysis, the biosynthetic intermediates for cephalosporin antibiotics including isopenicillin N, deacetoxycephalosporin C, deacetylcephalosporin C and unknown cephem compound were detected in reaction mixtures. It implies that cephabacin compounds from L lactamgenus could be produced by biosynthetic routes through penicillin ring formation and its expansion to cephalosporin ring, likely as cephalosporin C from Cephalosporium or cephamycin C from Streptomyces. Among biosynthetic enzyme in cell-free extract, the ring formation activity (isopenicillin N synthetase activity) was separated in 50-60% of ammonium sulfate fraction, and ring expansion activity (deacetoxycephalosporin C synthetase activity) was found to be in 40-50% fraction. The partially purified isopenicillin N synthetase could convert as much as 90% ACV to isopenicillin N during 6-hour reaction.

• Bulletin of the Korean Chemical Society
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• 제23권5호
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• pp.749-757
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• 2002

Chiral oxazolidin-2-one is easily prepared from D-mannitol and demonstrated to undergo highly diastereoselective alkylation reactions via lithium imide Z-enolates of its N-acyl derivatives to afford ${\alpha}-branched$ products. Evans syn and non-Evans sy n aldol products were also selectively obtained using this new auxiliary in high diastereomeric purity by simply changing the stoichiometry of TiCl4 and the nature of the amine base. Also, this new auxiliary is employed in diastereoselective Staudinger-type ${\beta}-lactam$ syntheses. Using 2-chloro-1-methylpyridinium iodide as the dehydrating agent, the reaction of auxiliary tethered acetic acid with trans imines gave the desired ${\beta}-lactams$ with cis-selectivity.

• 약학회지
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• 제28권4호
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• pp.243-248
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• 1984

For gas chromatographic determination with the sulfur-specific flame photometric detector, nine ${\beta}$-lactam antibiotics without ${\alpha}$-amino group were esterified with borontrifluoride-methanol complex and then N-benzoylated with benzoyl chloride. The gas chromatographic separation of these products was successfully carried out on various silicon polymers (OV-1, OV-101, OV-17, OV-225, and QF-1) coated on the acid washed, silanized diatomite. The structure of the esterified and N-benzoylated product was confirmed by mass spectromer.