• Bulletin of the Korean Chemical Society
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• v.15 no.6
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• pp.513-515
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• 1994

• Bulletin of the Korean Chemical Society
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• v.19 no.5
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• pp.598-601
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• 1998

• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2673-2678
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• 2014

The detailed mechanisms of the efficient $\small{L}$-proline and pyrrolidine catalyzed transamidation of acetamide with benzylamine have been investigated using density functional theory (DFT) calculations. Our calculated results show: (1) the mechanisms of two catalytic cycle reactions are similar. However, the rate-determining steps of their reactions are different for the whole catalytic process. One is the intramolecular nucleophilic addition reaction of 1-COM, the other is hydrolysis reaction of 2-C. (2) COOH group of $\small{L}$-proline is essential for efficient transamidation. The computational results are in good agreement with the experiment finding and mechanism resported by Rao et al. for $\small{L}$-proline-catalyzed synthesis of amidesin good to excellent yields.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.705-712
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• 2006

The synthesis of a new series of 1 $\beta$-methylcarbapenems having 5-(1,2-disubstituted ethyl)pyrrolidine moiety are described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria were tested and the effect of substituents on the pyrrolidine ring was investigated. Among them, compound (IIIc) having 1-methoxyimino-2-hydroxyethyl moiety showed the most potent antibacterial activity.

• Analytical Science and Technology
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• v.7 no.1
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• pp.79-89
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• 1994

Interactions between the acetonitrile and other organic molecules such as furan, pyrrole, pyrrolidine, thiophene, tetrahydrothiophene and acetaldehyde was studied with the infrared absorption spectroscopy under matrix isolation conditions. Xe was used as a major matrix material. Acetonitrile showed strong interactions with pyrrole and thiophene, and little interactions with pyrrolidine and acetaldehyde.

• Bulletin of the Korean Chemical Society
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• v.27 no.8
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• pp.1164-1170
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• 2006

The synthesis of a new series of 1$\beta$-methylcarbapenems having 5-($\alpha,\beta$-disubstituted ethyl)pyrrolidine moiety is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria were tested and the effect of substituents on the pyrrolidine ring was investigated. A particular compound (VIh) having $\alpha$-hydroxy-$\beta$-piperazinylethyl substituted moiety showed the most potent activity.

• Journal of the Korean Chemical Society
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• v.59 no.1
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• pp.31-35
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• 2015

Diastereoselective reduction of 2,3-dioxo-4-carboxy-5-(substituted)pyrrolidine 1 by $NaBH_4/AcOH$ and heterogenous hydrogenation were reported. Stereochemical assignment and diastereomeric ratios of the products were determined using $^1H$ NMR and single crystal X-ray analyses. The steric factors of the C-5 substituents of the pyrrolidinone was shown to have an interesting influence on both the yield and diastereoselectivity of the reduced product.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2467-2472
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• 2010

Twenty novel tetramic acid derivatives (E)-3-(1-(alkyloxyamino)ethylidene)-1-alkylpyrrolidine-2,4-diones were synthesized by the reaction of 3-(1-hydroxyethylidene)pyrrolidine-2,4-diones with O-alkyl hydroxylamines. The title compounds were confirmed by IR, $^1H$ NMR, MS and elemental analysis. The structure of compound 6r was further verified by X-ray diffraction crystallography. The bioassays showed that most of the title compounds exhibited noticeable herbicidal and fungicidal activities.

• Korean Journal of Pharmacognosy
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• v.39 no.2
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• pp.91-94
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• 2008

Column chromatographic separation of the MeOH extract from the aerial parts of Paris verticillata led to the isolation of three phenolics, two terpene glucosides and two pyrrolidine alkaloids. Their structures were characterized to be methyl caffeate (1), 5-hydroxy pyrrolidin-2-one (2), vanillic acid (3), benzyl alcohol glucopyranoside (4), (6S, 9R)-roseoside (5), staphylionoside H (6) and 5-methoxy pyrrolidin-2-one (7) by spectroscopic means. The isolated compounds (1-7) were for the first time reported from this source. The isolated compounds were tested for their cytotoxicity against four human tumor cell lines by SRB method in vitro.

• YAKHAK HOEJI
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• v.43 no.3
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• pp.306-315
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• 1999

To develop new cephalosporin antibiotics with improved antibacterial activities, a series of 7$\beta$-[2-(2-aminothiazol-4-y)-(Z)-2-(1-carboxy-1-methylethoxyimino)acetamido] -3-[5-(heterocycle)thiomethylpy-rrolidin-3-ylthio]methyl-3-cephem-4-carboxylic acid (14~18) having aminothiazol carboxymethylethoxy-imino group on the C-7 position and (heterocycle) thiomethyl pyrrolidinthiomethyl group on the C-3 position of the cephem ring were synthesized. These compounds were tested for antimicrobial activity in vitro against Gram(+) and Gram(-) bacteria. Compounds 15 and 16 showed remarkable antibacterial activity against Salmonella typhimurium TV119 and Alcalienes faecalis KCTC1004, but most of compounds showed lower activity than cefotaxime.