Enzymatic nucleic acids containing 5′-and or 3′-cap structures

A nucleic acid molecule comprising a 5′-cap structure, a 3′-cap structure, or both a 5′- and a 3′-cap structure, wherein said 5′-cap structure is selected from the group consisting of 4′,5′-methylene nucleotide;

• 1-(β-D-erythrofuranosyl) nucleotide;
• 1,3-diamino-2-propyl phosphate, 3-aminopropyl phosphate;
• 12-aminododecyl phosphate;
• hydroxypropyl phosphate;
• 1,5-anhydrohexitol nucleotide;
• L-nucleotide;
• threo-pentofuranosyl nucleotide;
• acyclic 3′,4′-seco nucleotide;
• 3,5-dihydroxypentyl nucleotide;
• and 5′-mercapto moieties, and wherein said 3′-cap structure is selected from the group consisting of 1,5-anhydrohexitol nucleotide;
• L-nucleotide;
• threo-pentofuranosyl nucleotide;
• acyclic 3′,4′-seco nucleotide;
• 3,5-dihydroxypentyl nucleotide;
• 3′-2′-inverted nucleotide moiety;
• 3′-2′-inverted abasic moiety;
• and 1,4-butanediol.