• Journal of Korean Ophthalmic Optics Society
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• v.14 no.3
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• pp.95-102
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• 2009

Purpose: The purpose of this study is to investigate antimicrobial activity of ally derivative of garlic against eye diseases, and to get basic data for an application development of the derivative, as a natural preservative, to multi-purpose solution (MPS). Methods: Antimicrobial activity of allyl derivative of garlic, diallyl sulfide (DAS), against Pseudomonas aeruginosa (P. aeruginosa) and Staphyloccus aereus (S. aereus) was determined. After DAS treatment in MPS of no microbial activity, its growth inhibition effect to bacteria was also determined. Results: DAS concentrations of $IC_{50}$ against P. aeruginosa and S. aereus were found when both bacteria were treated with DAS concentration of 0.25% and 0.64%, respectively. At MPS test, a product from Company A did not show any effects against both bacteria, but one from Company B showed antimicrobial activity against both bacteria. Antimicrobial activity test of the product from Company B in MPS did not showed any significant difference on both gram-negative and gram-positive bacteria. For a trial application of antimicrobial activity of DAS as a natural preservative, DAS was added to MPS of Company A which did not show any antimicrobial activity at treated concentration. Addition of DAS into MPS of Company A resulted in antimicrobial activity of DAS, which suggested a possible application of DAS as a germicide for contact lenses. Conclusions: This study showed allyl derivative of garlic has antimicrobial activity against both P. aeruginosa and against S. aereus, but more effects on P. aeruginosa. The result suggests that allyl derivative derived from garlic can be developed to a preservative of MPS as a natural substance.

• Natural Product Sciences
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• v.5 no.2
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• pp.93-96
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• 1999

A new ergosteryl myristate (1) and ergosterol (2) have been isolated from the organic extract of the mycelium of unidentified marine algicolous fungus, isolate MF001. The structure of a new compound was assigned on the basis of comprehensive spectroscopic analyses and chemical synthesis.

• Natural Product Sciences
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• v.24 no.3
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• pp.155-158
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• 2018

A new flavonol derivative, meliglabrin (1) along with three known flavonols, ternatin (2), meliternatin (3), and 5,4'-dihydroxy-3,7,3'-trimethoxyflavon (4) were isolated from the leaves of Melicope glabra (Blume) T.G. Hartley. Their structures were determined using extensive spectroscopic methods, including UV, IR, HRESIMS, 1D and 2D NMR. Compounds 1 - 4 were evaluated for their cytotoxicity against murine leukemia P-388 cells, compound 4 showed moderate activity.

• Natural Product Sciences
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• v.9 no.1
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• pp.18-21
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• 2003

Guided by the brine shrimp lethality assay, a new (4) and three known cyclitol derivatives (1-3) were isolated from the marine sponge Stelletta sp. Norsarcotride A (4) showed significant cytotoxicity against a small panel of five human tumor cell lines.

• Natural Product Sciences
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• v.21 no.4
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• pp.248-250
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• 2015

A new ${\alpha}-pyrone$ derivative, violapyrone J (1), and along with the two known violapyrones B (2) and C (3) were isolated from the fermentation broth of a marine actinomycete Streptomyces sp. SC0718. The structure of violapyrone J (1) was elucidated from 1D and 2D NMR spectroscopic analyses.

• Natural Product Sciences
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• v.21 no.4
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• pp.293-296
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• 2015

A new L-isoascorbic acid derivative epi-leptosphaerin (1) and two known compounds leptosphaerin (2), and verongamine (3) were isolated from sponges of the orders Verongida and Thorectidae. Compounds 1 and 2 are most likely of sponge-associated fungal origin. In the present study, isolated compounds were investigated for their inhibition of soluble epoxide hydrolase (sEH), which is considered a promising target for the management of pain, inflammation, and comorbidities associated with diabetes. Compound 3, verongamine, displayed weak inhibitory activity against sEH with an $IC_{50}$ value $51.5{\pm}1.0{\mu}M$.

• Bulletin of the Korean Chemical Society
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• v.22 no.6
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• pp.553-558
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• 2001

A stereoselective synthesis of $1\beta-aminocarbapenems$ (11a-c) starting from-4-acetoxy-2-axetidinone derivative 4 is described. 4-Acetoxy-2-azetidinone derivative (4) was reacted with lithium enolate of benzophenone limine of glycine phenyl ester (5f) to give alkylated product (R)-6f in good yield with high diastereoselectivity. The alkylated procudt (R)-6f was transformed to thioesters (7a-c) by transesterification with thiols, Thioesters (7a-c) were converted to their oxalimides (8a-c), followed by the phosphite-mediated reductive cyclization to give carbapenems (9a-c). Removal of all protecting groups of carbapenems (9a-c) afforded $1\beta-aminocarbapenems$ (11a-c).

• Wind and Structures
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• v.28 no.6
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• pp.347-354
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• 2019

This study provides an approximate analytical solution to the fractional vibration problem of thin plate governing anomalous motion of plate subjected to in-plane loads. The method of variable separable is employed to transform the fractional partial differential equations under consideration into a fractional ordinary differential equation in temporal variable and a bi-harmonic plate equation in spatial variable. The technique of conformable fractional derivative is utilized to solve the resulting fractional differential equation and the approach of finite sine integral transform method is used to solve the accompanying bi-harmonic plate equation. The deflection field which measures the transverse displacement of the plate is expressed in terms of product of Bessel and trigonometric functions via the temporal and spatial variables respectively. The obtained solution reduces to the solution of the free vibration problem of thin plate in literature. This work shows that conformable fractional derivative is an efficient mathematical tool for tracking analytical solution of fractional partial differential equation governing anomalous vibration of thin plates.

• Natural Product Sciences
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• v.26 no.4
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• pp.279-282
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• 2020

Chemical investigation of the methanol extract of Koordersiodendron pinnatum Merr. leaves resulted a new naphthalene derivative, (Z)-4-(tetradec-3-enyl)naphthalene-1,2,7-triol (1), together with three known compounds, ��-sitosterol (2), 20-epibryonolic acid (3), and scopoletin (4). The structure of the new compound was elucidated based on spectroscopic evidence. The isolated compounds (1-4) were tested their cytotoxic activities against the P-388 murine leukemia cell line and compound 1 has highest activity with IC50 1.94 μM.

• Bulletin of the Korean Mathematical Society
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• v.50 no.5
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• pp.1683-1691
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• 2013

In this paper, we obtain the criteria that the Riemannian manifold B is Einstein or a gradient Ricci soliton from the information of the second derivative of $f$ in the warped product space $R{\times}_fB$ with gradient Ricci solitons. Moreover, we construct new examples of non-Einstein gradient Ricci soliton spaces with an Einstein or non-Einstein gradient Ricci soliton leaf using our main theorems. Finally we also get analogous criteria for the Lorentzian version.