• 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.233.2-233.2
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• 2002

Apio nucleosides whose 4'-hydroxymethyl group moves to 3'-position exhibit interesting biological activity such as antitumor or antiviral activity. On the other hand. neplanocin A is the representative of the carbocyclic nucleosides and has been recognized as a potent antitumor and antiviral agent. Based on these findings. it was of great interest to design apio neplanocia A which combined the properties of apio nucleosides and neplanocin A. (omitted)

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.501-506
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• 1997

Novel 9-[2-fluoro-4-hydroxy-3-hydroxymethyl-2-butenyl]adenine and its related compounds were designed and synthesized as open-chain analogues of neplanocin A. Alkylation of adenine or pyrimidine bases with the mesylate 4 was chosen as a simple approach to the synthesis of 2-fluoro-2-butenylated nucleosides. Mesylate 4 was prepared from dihydroxyacetone dimer via four steps in 58% overall yield. The synthesized compounds were evaluated their antiviral activity against HSV, HIV and Polio viruses.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.302-309
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• 2000

Based on (-)-neplanocin A with the 5'-hydroxyl substituted with fluoro, azido, or amino group, the corresponding xylo- and arabino derivatives were synthesized from D-ribose using the Mit-sunobu reaction as a key step. None of the final nucleosides did show either significant antiviral activities or cytotoxicities.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.245.3-246
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• 2003

S-Adenosylhomocysteine hydrolase (SAH) catalyzes the hydrolysis of S-adenosylhomocysteine to adenosine and L-homocysteine and has been an attractive target for the development of broad spectrum antiviral agents. Based on the potent inhibitory activity of neplanocin A against SAH, we have reported the synthesis and novel mechanism of action of fluoro-neplanocin A. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.241.1-241.1
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• 2003

Apio nucleosides whose 4'-hydroxymethyl group moves to 3'-position exhibit interesting biological activity such as antitumor or antiviral activity. On the other hand, neplanocin A and aristeromycin are the representative of the carbocyclic nucleosides and have been recognized as potent inhibitors of S-adenosylhomocysteine hydrolase. Based on these findings. it was of great interest to design apio analogues of neplanocin A and aristeromycin. (omitted)

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.219.1-219.1
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• 2001

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.354.1-354.1
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• 2002

Carbocyclic nucleosides are unique class in which a methylene group replaces the oxygen in the furan, which result in metabolic stability to endogenous phosphorylase. The biologically active natural carbocyclic nucleosides such as aristeromycin and neplanocin were found to possess interesting biological properties including antiviral and antitumor activity. (omitted)

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.365.2-365.2
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• 2002

S-Adenosylhomocysteine hydrolase (SAH) catalyzes the hydrolysis of S-adenosylhomocysteine to adenosine and L -homocysteine and has been an attractive target for the development of broad spectrum antiviral agents. Neplanocin A and 9-(dihydroxycyclopent-4' -enyl)adenine (DHCeA) have been known to inhibit SAH by cofactor (NAD＋) depletion mechanism and their inhibition is reversed by the addition of NAD＋ or dialysis. (omitted)

• Bulletin of the Korean Chemical Society
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• v.30 no.9
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• pp.2043-2050
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• 2009

2′-$\beta$-C-Methylneplanocin A (3) was synthesized via 2-$\beta$-C-methylribonolactone, prepared by a modified Whistler and BeMiller’s method developed by our laboratory, as potential anti-HCV agent. Reduction of 14 with Dibal-H afforded 26 in a good yield with a trace of 25, whereas a Luche reduction gave 26/25 = 4/1 mixture. Several attempts were made to chemoselectively remove TBS group in the presence of TBDPS group and treatment with both PPTS and TsOH showed the best result. Condensation of 26 with 6-chloropurine under Mitsunobu conditions produced an $S_N$2 product 27 along with an $S_N$2′ product 28.