• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.731-741
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• 2009

‘One-pot’ reaction procedure for the synthesis of novel morpholino pyrimidines (10-18) under microwave irradiation in ‘dry media’ in the presence of heterogeneous $NaHSO_4.SiO_2$ catalyst was developed. All the synthesized compounds were screened for their in vitro antibacterial activities against clinically isolated bacterial strains namely Bacillus subtilis, Bacillus cerues, Micrococcus luteus and Salmonella typhii and antifungal activities against fungal strains namely Aspergillus niger, Candida 6 and Candida 51. Structure activity relationship of the synthesized compounds against microbiological results was discussed.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.489-492
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• 1995

A new synthetic route to chiral liquid crystal dopant, 4-[2-(7S-methylnonanyl)oxy-5-pyrimidinyl]phenyl(2S,3S)-2-chloro-3-methylpentanoate (1), starting from 4-nitrophenylacetic acid is described. The key intermediate methylthiopyrimidine compound (8) has been synthesized from 4-nitrophenylacetic acid by Vilsmyer-Haack reaction followed by the formation of pyrimidine ring, and then converted to chiral ester (1) by the replacement of nitro group by (2S,3S)-2-chloro-3-methylpentanoic acid 2 through the formation of diazonium salt.

• Bulletin of the Korean Chemical Society
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• v.9 no.5
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• pp.295-298
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• 1988

Acyclic nucleosides, 1-[[1,3-bis(benzyloxy)-2-propoxy]methyl]-2-thiopyrimidine, 9-[[1,3-bis(benzyloxy)-2-propoxy]methyl]-6-amino -2-thiopurine, 1-(2-acetoxyethoxymethyl)-2-thiopyrimidine, and 9-[[1,3-bis(benzyloxy)-2-propoxy]methyl]-6-amino -2-thiopurine have been synthesized by coupling pyrimidine and purine bases with acyclic acetates using a new coupling reagent of lithium bromide in the presence of trifluoro acetic acid in acetonitrile.

• Archives of Pharmacal Research
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• v.23 no.2
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• pp.128-138
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• 2000

In continuation of the previous work (Fathalla, 1992) on the synthesis of some heterocycles containing uracil moiety, we report herein the incorporation of uracil moiety into cyan-opyridine thione, thiosemecarbazone, semicarbazone, cyanopyridine, ami nocyano pyridine, isoxazoline, pyrazoline, pyrimidine, triazolo pyrimidine, pyran, selena and thiazole derivatives which might modify their biological activities. The biological studies revealed that the chemical compound III f showed high molluscicdal activity than other compounds. The profile of the nucleoprotein extracted from chemically (compound IIIc, e, f and g) treated or UV-irradiated B.alexandrina snails did not show appreciable differences when compared to non-treated (native) snails by using SDS-PAGE, where no obvious qualitative or quantitative differences were observed. Immunization of experimental animals with the nucleoprotein extracted from native, chemically (compound III f ＆ g) treated or physically treated B.alexandrina snails induced significant protection against challenge with normal S.mansoni cercariae, as compared to the non-immunized challenged control. As well as , a decrease in the number of granuloma formation and the size range of granuloma was also observed in immunized animals. It is concluded that, compounds III f and g have a potent molluscicidal activity. They also induced chemical modification comparable to that induced by physical treatment in the snail's nucleoprotein, which could possibly be used in immunization against S. mansoni infection.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.714-716
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• 2012

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2004.10a
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• pp.29-34
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• 2004

Reduction in stratospheric ozone layer increases the amount of ultraviolet-B radiation (UVB: 280-320 nm) that reaches the earth ’ s surface. UVB radiationcan damage plants, resulting in decrease in growth and productivity. UVB-augmentation studies have indicated that the sensitivity to UVB radiation in plants varies among the species and cultivars. However. there are no definitive answers for the mechanisms of UVB-resistance in higher plants and for bioengineering design and development of UVB-tolerant plants. We have been studying physiological and biochemical aspects of the effects of UVB radiation on growth and yield of rice COryza sativa LJ. aiming to clarify the mechanism of resistance to UVB radiationin rice. At this meeting. weintroduce our research as followed: (1) supplementary UVB radiation has inhibitory effects on the growth. yield and grain development of rice; (2) UVB sensitivity of rice varies widely among cultivars; (3) among Japanese rice cultivars. Sasanishiki. a leading variety in northeast Japan. is more resistant to UVB. while Norin 1. a progenitor of Sasanishiki. is less resistant; (4)UV-sensitive Norin 1 cultivar is deficient in photorepair of UVB-induced cyclobutane pyrimidine dimer (CPD). and this deficiency results from one amino acid residue alteration of CPD photolyase. These results suggest that spontaneously occurring mutation in CPD photolyase gene could lead to difference in UVB sensitivity in rice. and that CPD photolyase might be a useful target for improving UVB-sensitivity in rice by selective breeding or bioengineering of UVB-tolerant rice.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.990-996
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• 2003

A novel carboacyclic nucleoside analogue, 9-[2-bromo-4-hydroxy-3-hydroxymethyl-2-butenyl] adenine, and its derivatives were designed and synthesized as open-chain analogues of neplanocin A. The syntheses were accomplished via the coupling of adenine or pyrimidine bases to the key intermediate allylic bromide 7. The bromide 7 was prepared from epichlorohydrin in a seven step process in a 54% overall yield. The synthesized compounds were evaluated for their antiviral activity against the polio virus, HSV and HIV.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.363.2-363.2
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• 2002

A number of 2',3'-deoxynucleosides have been discovered to possess significant antiviral activity against HIV-1 and other viruses. Since it has been suggested that proper conformation of the dideoxynucleosides in terms of ring puckering of the five-membered sugar moiety is required for them to exhibit antiviral activity a number of nucleoside analogues to fix sugar-ring puckering have been synthesize and evaluated for antiviral activity. (omitted)

• Journal of Photoscience
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• v.9 no.2
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• pp.162-165
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• 2002

Rice is widely cultivated in various regions throughout Asia. Over a five-year period, we investigated the effects of supplemental UVB radiation on the growth and yield of Japanese rice cultivars in the field. The findings of that study indicated that supplemental UVB radiation has inhibitory effects on the growth and grain development. Furthermore, we investigated the sensitivity to UVB radiation of rice cultivars of 5 Asian rice ecotypes, and found that rice cultivars vary widely in UVB sensitivity. The aim of our study is improving UVB resistance in plants by bioengineering or breeding programs. In order to make it, there is need to find the molecular origin of the sensitivity to UVB. Cyclobutane pyrimidine dimer (CPD) is major UV-induced DNA lesions. Plants possess two mechanisms to cope with such DNA damage. The first is the accumulation of UV-absorbing compounds. Our previous data showed that the steady-state CPD levels in leaves of rice grown under chronic radiation in any culture were not so greatly influenced by the increased UV-absorbing compounds content, although there was a significant positive correlation between the CPD levels induced by challenge UVB exposure and the UV-absorbing compounds content. The other is the repair of DNA damage. Photorepair is the major pathway in plants for repairing CPD. We found that the sensitivity to UVB could seriously correlate with the low ability in CPD photorepair in rice plants. These results suggest that photo lyase might be an excellent candidate for restoration by way of selective breeding or engineering in rice.

• YAKHAK HOEJI
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• v.25 no.4
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• pp.167-173
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• 1981

Spectroscopic investigation has been carried out to know the binding mechanism of riboflavin with barbiturates, such as phenobarbital and amobarbital in chloroform solution by using infrared and nuclear magnetic resonance spectra. Phenobarbital and isoalloxazine form a 1:1 cyclic hydrogen bonded dimer through the 3-N imino and the 2-C carbonyl groups of the isoalloxazine ring of the latter, and the 1-N (or 3-N) imino and the 2-C carbonyl groups of the pyrimidine ring of the former. Amobarbital and riboflavin form a 1:1 cyclic hydrogen bonded dimer by the same mode of phenobarbital.