Enantiomers of 1′,6′-isoneplanocin, including derivatives of the enantiomers of 1′,6′-isoneplanocin, are disclosed along with novel synthetic methods. In particular, a substituted cyclopentane epoxide is synthesized into the enantiomers of 1′,6′-isoneplanocin. Enantiomers of carbocyclic nucleoside analogs of 3-deazaneplanocin to provide D- and L-like 1′,6′-iso-3-deazaneplanocin are also disclosed. The small molecule chemotherapeutic compounds beneficially provide DNA and RNA antiviral activity, demonstrating activity towards, for example, human cytomegalovirus, measles, Ebola, norovirus, dengue, vaccinia and HBV. Compounds exhibiting reduced S-adenosylhomocysteine hydrolase inhibitory effects are disclosed and provide improved toxicity profiles in comparison to neplanocin. The invention provides improved prophylactic and/or therapeutic antiviral efficacy.
