Facile synthesis of 9-[(1′R,2′S)-2′-hydroxy-3′-oxocyclopentan-1′-yl]-9-H-adenine possessing inhibitory activity against human recombinant S-adenosyl-l-homocysteine hydrolase

Treatment of 4′-O-methanesulfonyl-2′,3′-O-isopropylidenenoraristeromycin with KOBut gave the corresponding 3′,4′-dehydro derivative, and subsequent deprotection resulted in the formation of 9-[(1′R,2′S)-2′-hydroxy-3′-oxocyclopentan-1′-yl]-9-H-adenine possessing inhibitory activity against human recombinant S-adenosyl-l-homocysteine hydrolase (EC 3.3.1.1). In sharp contrast to KOBut, when lithium azide was adopted as a base, 9-[(1′R,2′S,3′R)-2′,3′-O-isopropylidenedioxy-4′-cyclopenten-1′-yl]-9-H-adenine was selectively obtained, and subsequent deprotection afforded DHCeA, which is a well-known potential antiviral agent.