• Asian-Australasian Journal of Animal Sciences
• /
• v.1 no.4
• /
• pp.219-222
• /
• 1988

Degradation of deoxyribonucleic acid(DNA) and ribonucleic acid(RNA) by cell-free extract of mixed rumen protozoa of buffalo rumen was investigated. DNA was observed to be degraded rapidly during an initial incubation period of 2 hr with simultaneous appearance of degradation products. RNA on the other hand recorded a rapid degradation during an initial incubation period of 1 hr. RNA degradation products appeared upto an incubation period of 2 hr. DNA was observed to degrade into oligo- and mononucleotides. pyrimidine nucleosides, purine nucleoside adenosine and bases xanthine, hypoxanthine and thymine. Degradation products of RNA comprised of pyrimidine nucleosides, purine nucleoside, adenosine and bases xanthine, hypoxanthine and uracil besides oligo- and mononucleotides.

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1993.04a
• /
• pp.114-114
• /
• 1993

항암성 또는 항 virus성 약물개발 목적으로 천연의 pyrimidine nucleoside의 구조유사체로 pyrimidine acyclonucleoside들을 합성하였다. Pyrimidine acyclonucleoside를 염기 uracil, thymine 및 5-fluorouracil을 원료로 하여 합성하고 구조를 NMR, IR data를 써서 확인하였다. 이들 합성 화합물들은 L$_{1210}$ 암세포를 이용하여 in vitro 항암성 작용을 검색하였다. 합성된 화합물들 중 5-fluorouraoil-acyclonucleoside들은 약간이나마 모 5FU보다 높은 항암성 작용을 보였다. 유도체들은 5-FU의 N$^1$에 glycosidic 결합이 아닌 alkyl 결합을 하고있어, 모 5FU를 그리 쉽게 유리시키리라 보아지지 않으므로 이들의 작용성은 acyclonucleoside형태일 것 같아 이들의 작용기전 연구가 필요하다고 보아진다. 한편 얻은 유도체들은 HSV-1 및 HSV-2를 이용하여 항 virus성 작용을 검색한 결과 2500$\mu\textrm{g}$/ml 농도에서 유의성 있는 억제 작용성을 보이지 않았다.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.11
• /
• pp.3348-3352
• /
• 2010

Novel 4'-ethyl-5'-norcarbocyclic adenosine phosphonic acid analogues were synthesized from propionaldehyde 5 through a de novo acyclic synthetic route using reiterative Grignard additions and ring-closing metathesis (RCM) as key reactions. The synthesized nucleoside phosphonic acids analogues 17, 18, 19, and 21 were subjected to antiviral screening against human immunodeficiency virus.

• Korean Journal of Microbiology
• /
• v.29 no.1
• /
• pp.25-33
• /
• 1991

Antiviral activities of papaverine and nucleoside analogs, 9-[(1,3-dihydroxy-2-propoxy)methyl]guanine (DHPG) and acyclovir, against human cytomegalovirus (HCMV) infection were compared in vitro. Papaverine and DHPG were effective in reducing infectious HCMV yields with $ED_{50}{\s}$ (effective dose 50: the concentraion at which 50% of virus yields was obtained) of approximately 1.02 and $0.45{\mu}{\M}$, respectively; while acyclovir was less effective with an $ED_{50}$ of about $10.4{\mu}{\M}$The relative cytotoxicity of these drugs was evaluated under the same conditions used to measure infectious HCMV yields. Papaverine and DHPG demonstrated little cellular toxicity as measured by their effect on the viability of confluent cells at concentrations in the range of those demonstrating potent inhibition of HCMV replication. Similarly, protein synthesis was largely unaffected by these drugs in stationary mock-infected cells as measured by the incorporation of isotopically labelled amino acids. In contrast, cellular DNA synthesis was invariably reduced in the presence of either drug. HCMV-specific DNA synthesis was also strongly inhibited by papaverine and DHPG.

• YAKHAK HOEJI
• /
• v.56 no.4
• /
• pp.230-235
• /
• 2012

Synthesis of novel cyclopropyl pyrimidine and purine nucleoside derivatives 2~8 with ${\alpha}$-configuration was successfully accomplished using an epoxide-ring opening reaction, lactonization, a hydroboration-oxidation reaction and a Mitsunobu reaction as the key steps. Antiviral activities against HSV-1 and -2, HIV-1 and -2, coxsackie B1and B3 viruses and poliovirus were assayed. Three compounds 4, 7 and 8 exhibit cytotoxicity-derived antiviral activity only in HIV-1 and -2.

• Bulletin of the Korean Chemical Society
• /
• v.30 no.11
• /
• pp.2626-2630
• /
• 2009

2'($\beta$)-Hydroxymethylated adenosine is a potent and selective inhibitor of hepatitis C virus (HCV) replication. It targets the RNA-dependent RNA polymerase of HCV, NS5B. Synthesis and antiviral evaluation of carbocyclic versions are described. The cyclopentene intermediate ($9\beta$) was successfully synthesized through sequential Johnson-Claisen orthoester rearrangement and ring-closing metathesis (RCM). Coupling of bases via a Pd(0) catalyst, selective dihydroxylation, and desilylation yielded the target nucleoside analogues. The compounds 17 and 18 were assayed for their ability to inhibit HCV RNA replication in a subgenomic replicon Huh7 cell line and showed moderate antiviral activity with toxicity up to 20.0 and 24.7 ${\mu}g/mL$, respectively.

• Bulletin of the Korean Chemical Society
• /
• v.26 no.10
• /
• pp.1520-1524
• /
• 2005

This paper describes the racemic and stereoselective synthetic route for a novel 4'$\alpha$-phenyl and 6'$\alpha$-methyl doubly branched carbocyclic nucleosides from an acyclic 2-hydroxy acetophenone. The installation of phenyl group at the 4'-position of carbocyclic nucleoside was successfully accomplished via a sequential [3,3]-sigmatropic rearrangement. The stereoselective introduction of a methyl group in the 6'$\alpha$-position was accomplished by Felkin-Anh controlled alkylation. Bis-vinyl 11 compound was successfully cyclized using a Grubbs’ catalyst II to desired carbocycles. The natural bases (adenine and cytosine) were efficiently coupled using a Pd(0) catalyst. Although all the synthesized compounds were examined for their activity against several viruses such as HIV-1, HSV-1, HSV-2 and HCMV, only cytosine analogues 17 exhibited weak antiviral activity against HCMV.

• Archives of Pharmacal Research
• /
• v.29 no.6
• /
• pp.431-458
• /
• 2006

As we approach the completion of the first 25 years of the human immunodeficiency virus(HIV) epidemic, there have been dramatic improvements in the care of patients with HIV infection. These have prolonged life and decreased morbidity. There are twenty currently available antiretrovirals approved in the United States for the treatment of this infection. The medications, including their pharmacokinetic properties, side effects, and dosing are reviewed. In addition, the current approach to the use of these medicines is discussed. We have included a section addressing common comorbid conditions including hepatitis B and C along with tuberculosis.

• YAKHAK HOEJI
• /
• v.51 no.2
• /
• pp.103-107
• /
• 2007

In these study novel 1,4-disubstituted carbocyclic nucleoside analogues were synthesized as potential antiviral agents. The coupling reaction of the alcohol 8${\alpha}$ with natural bases using Mitsunobu reaction afforded the target nucleosides 13, 14. The synthesized compounds were evaluated for their antiviral activity against various viruses such as HIV-1, HSV-1, HSV-2 and HCMV. Cytosine derivative 13 exhibited moderate antiviral activity against HIV-1 (EC$_{50}$=16.4 ${\mu}$M).

• Natural Product Sciences
• /
• v.13 no.2
• /
• pp.140-143
• /
• 2007

Investigation of the chloroform soluble fraction of the red alga Liagora farinosa, collected from Hurghada at the Red Sea resulted in the isolation of three compounds; a nucleoside (thymidine) and two glycosides (methyl-${\beta}$-D-xylopyranoside and glycerol-2-${\alpha}$-D-glucopyranoside). The structures of the isolated compounds were established on the basis of different spectroscopic techniques as well as comparison with the previously published data. This is the first report for the isolation of the three compounds fron red algae; moreover, the compounds were examined for their antioxidant activity and showed variable activity.