• Bulletin of the Korean Chemical Society
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• v.29 no.9
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• pp.1815-1818
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• 2008

• Bulletin of the Korean Chemical Society
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• v.25 no.9
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• pp.1351-1354
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• 2004

Tetracyclic 5-azaindole analogues were prepared by palladium-catalyzed sequential annulation of benzylidene(3-iodopyridinyl-4-yl)amine and 1-aryl substituted internal alkynes under $Pd(OAc)_2,\;n-Bu_4NCl,\;and Et_3N\;at\;120^{\circ}C.$ The synthetic procedure showed possible diversification of tetracyclic 5-azaindole analogues by varying the 1-aryl substituent in internal alkynes.

• Journal of the Korean Chemical Society
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• v.38 no.1
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• pp.80-86
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• 1994

The synthetic pathway of ethyl $({\pm})$-8-oxo-10-oxa-l'H-spiro[1, 3]dioxolane-4,4'-tricyclo [9.2.1.0 1,6]dodec-6-ene-9-carboxylate (7), an important intermediate for the total synthesis of bruceantin analogue, was developed. Ethyl 2-cyclohexanonecarboxylate and methyl vinyl ketone were employed as starting materials. Robinson annulation, allylic oxidation, regiospecific acylation and the formation of epoxy methano bridge ring were studied. 4,4a,5,6,7,8-Hexahydro-4a-hydroxy-2(3H)naphthalenone (14) was synthesized utilizing the unusual decarboethoxylation reaction discovered during ketalization of octalone (3).

• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.87-92
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• 2018

A series of pyrimidine annulated dihydropyrano[2, 3-c]pyrazole derivatives were synthesized and screened for their antimicrobial activity. The precursor, dihydropyrano[2, 3-c]pyrazole was synthesised under catalyst free condition using PEG-400 as reaction medium which facilitated improved yield compared to base catalyzed reaction. Wide scope of substrates, simple workup procedure and high yield even in the absence of catalyst are the major highlights of the protocol. Dihydropyrano[2, 3-c]pyrazoles on condensation with formic acid formed pyrimidine annulated dihydropyrano[2, 3-c]pyrazole derivatives. All the products are characterized using FTIR, $^1H-NMR$ and $^{13}C-NMR$ spectroscopic techniques. The molecules have shown good to moderate activity as antimicrobial agents when compared to the standard drug ciprofloxacin.

• Research in Plant Disease
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• v.13 no.3
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• pp.220-222
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• 2007

Rust disease on Korean Azalea (Rododendron yedoense) was occurred in Jeonju, Jeonbuk province of Korea. The typical symtoms of the disease appeared first as small yellowish spots on leaves. Uredinia were observed at hypophyllous of the leaves, yellow or dark yellow in color and globoid in shape with the size of $0.27{\sim}0.46{\times}0.31{\sim}0.61$ mm. Urediniospores were also observed in the leaves, yellow in color with globoid or ovoid in shape with the size of $17.1{\sim}29.2{\times}12.8{\sim}18.2{\mu}m$. Surface characterization of the spores revealed that these spores have papilla-like projections, which were made of $2{\sim}3$ annulation (SA; small annulate). Based on these morphological characterizations the causative fungus was identified as Chrysomyxa rhododendri.