• 대한화학회지
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• 제58권4호
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• pp.366-376
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• 2014

Synthesis, structural characterization, and biological activity studies of novel pyrido[2,3-d]pyrimidines (10a-h, 11a-h) are described. Cyclization of cynoacetamides (4, 5) with malonitrile (7) and aldehyde (6a-h) via Hantzsch pyridine synthesis afforded cyanopyridones (8a-h, 9a-h), which on cyclization with formic acid under microwave conditions led to the final product. All the reactions are significantly faster and the isolated yields are remarkably higher in microwave conditions compared to the conventionally heated reactions. The compounds were tested in vitro for their antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtillus, Staphylococcus aureus, and Micrococcus luteus and antifungal activity against Trichphyton longifusus, Candida albicans, Microsporum canis, Fusarium solani. Compounds 10b, 10e, 11b and 11e exhibited good antibacterial and antifungal activities compared with standards.

• Journal of Microbiology and Biotechnology
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• 제28권4호
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• pp.566-570
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• 2018

Because glycosylation of aesculetin and its 6-glucoside, aesculin, enhances their biological activities and physicochemical properties, whole-cell biotransformation and enzymatic synthesis methodologies using Neisseria polysaccharea amylosucrase were compared to determine the optimal production method for glycoside derivatives. High-performance liquid chromatography analysis of reaction products revealed two glycosylated products (AGG1 and AGG2) when aesculin was used as an acceptor, and three products (AG1, AG2, and AG3) when using aesculetin. The whole-cell biotransformation production yields of the major transfer products for each acceptor (AGG1 and AG1) were 85% and 25%, respectively, compared with 68% and 14% for enzymatic synthesis. These results indicate that whole-cell biotransformation is more efficient than enzymatic synthesis for the production of glycoside derivatives.

• Advances in nano research
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• 제1권1호
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• pp.35-42
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• 2013

Cockroach (Periplaneta americana) broth has been employed to assess its potential as a candidate source animal tissue for the synthesis of gold nanoparticles. The synthesis is performed akin to room temperature in the laboratory ambience. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of nanoparticles. The synthesis of nanoparticles might have resulted due to the activity of chitin, metallothioneine and tropomyosin. A possible involved mechanism for the biosynthesis of nanoparticles has also been proposed. This work further indicates that the animal wastes too can effectively participate in nano-transformations thereby helping in controlling the environmental pollution and subsequently the different diseases.

• Archives of Pharmacal Research
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• 제13권4호
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• pp.385-387
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• 1990

3-[(1-Methyl-1H-tetrazol-5-y)thiomethyl] is one of the most important side chains in cephaloporins. This side chain which occures in numerous antibacterial agents, suc as cefamandole, latamoxef, cefoperazone, and cefmenoxime, contributes remarkable potency and broad spectrum. For the continuous work of study on the development of broad spectrum cephalosporins, we become interested in the effect of structural modification of the substituent at the N-1 position of mercaptoterazole toward biological activity because our recent work had demonstraated that the arylsubstituted mercaptotetrazoles (Fig. 1) had favorable effect on the activity against gram-positive bacteria. The main focus of this report was to investigate the relationship between activity and functional groups in the mercaptotetrazole.

• Journal of Plant Biology
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• 제29권4호
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• pp.263-284
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• 1986

Effects of putrescine, spermidine and spermine on the activity of D-glucose-6-phosphate cyclohydrolase in the Daucus carota L. protoplast cultured for 4 days and effects of polyamines on the incorporation of D-[u-14C]-glucose treated to protoplasts in culture-medium were investigated. The activity of D-glucose-6-phosphate cyclohydrolase was increased by polyamines and among them spermine was the most effective. Polyamiens increased protein synthesis and this due to the increasing effect of the polyamines on the synthesis of glycoprotein which is one of cell wall components. The synthesis of cell polysaccharides, such sa pectic substances, hemicelluloses and cellulose was increased by polyamines, which stimulated synthesis of pectin substances, and hemicellulose more greatly than that of cellulose, and spermidine was the most effective. In the light of the above results it seems that the polyamines increase cell wall regeneration by the stimulation of enzyme activities which synthesize cell wall components.

• Journal of Industrial and Engineering Chemistry
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• 제67권
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• pp.231-235
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• 2018

In this study, we demonstrate the conversion of starch to (R,R)-2,3-butanediol (2,3-BD) in a hybrid cell-free synthesis system containing a mixture of lysates derived from Escherichia coli (E. coli) and cyanobacteria. A sufficient pool of pyruvate required for the synthesis of 2,3-BD was generated by combining metabolic pathways of cyanobacteria and E. coli. Successful synthesis of 2,3-BD was achieved by additional modifications of the hybrid cell-free system with the enzymes required to convert pyruvate to 2,3-BD. The results demonstrate a new approach to harness biological pathways to expand the scope of cell-free metabolic engineering by cross-species combinations of cell lysates.

• Environmental Analysis Health and Toxicology
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• 제16권3호
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• pp.115-120
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• 2001

The predictive screening of various molecular descriptors for predicting cyclooxygenase inhibitor, lipooxygenase inhibitor, leucotriene synthesis inhibitor, leucotriene antagonist activities of Stilbene moieties have been investigated for the application of quantitative structure-activity relationships (QSAR). The biological activities for 36 compounds were computed by the PASS program and molecular descriptors are cited from literatures or calculated, to investigate feasibility of screening relevant descriptors and of their applications among biological endpoints. Fairly good correlations varying from 0.7828 to 0.9032 were obtained using 12 descriptors with 29 Stilbene derivatives and 5 diazo-compounds. Our studies reveal that LogKow, electron density(X), electron density (Y),4th-order valence connectivity and water solubility can be usefully employed to predict biological activities of stilbene derivatives with simple regression models.

• Bulletin of the Korean Chemical Society
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• 제12권1호
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• pp.75-79
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• 1991

A series of compounds, N-(2-substituted-1-carboxy)vinylazetidinones were successfully synthesized in order to test the hypothesis that biological activities of ${\beta}$-lactam antibiotics could be attributed to the smooth flow of electrons after a nucleophilic attack at the carbonyl carbon in the ${\beta}$-lactam ring. After introduction of aminothiazolylacetamido group at 3-position of the azetidinones, their biological activities were evaluated. Their low activities led to the conclusion that the smooth electron flow in ${\beta}$-lactams in not the sufficient source for the biological activities.

• 대한화학회지
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• 제58권4호
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• pp.381-387
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• 2014

A series of new $N^7$-tetrazolo[5,1-f ]-1,2,4-triazin-8-(7H)-one derivatives 4-16 were designed and synthesized from 3 with different reagents. The newly prepared compounds were characterized by spectral data and screened for their antimicrobial activities against various bacteria and fungi strains.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.362.4-363
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• 2002

Costunolide which is known as a chemopreventive drug is a sesquiterpene compound isolated from Magnolia Sieboldii. and has antitumor and antiinflamatory activities. it is very hard to collect enough amount of natural extracts of costunolide for the activity studies. therfore. synthesis of costunolide derivatives is honestly needed. the aim of this research is to develope new methods for costunolide synthesis and to test biological activities. (omitted)