Enzymatic nucleic acids containing 5'-and/or 3'-cap structures

A method for producing an enzymatic nucleic acid molecule having activity to cleave an RNA or a single-stranded DNA molecule, comprising the step of forming said enzymatic nucleic acid molecule with 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',4'-methylene nucleotide;
• 1-(.beta.-D-erythrofuranosyl)nucleotide;
• 4'-thio nucleotide, carbocyclic nucleotide;
• 5'-amino-alkyl phosphate;
• 1,3-diamino-2-propyl phosphate, 3-aminopropyl phosphate;
• 6-aminohexyl phosphate;
• 12-aminododecyl phosphate;
• hydroxypropyl phosphate;
• 1,5-anhydrohexitol nucleotide;
• L-nucleotide;
• alpha-nucleotide;
• threo-pentofuranosyl nucleotide;
• acyclic 3',4'-seco nucleotide;
• 3,4-dihydroxybutyl nucleotide;
• 3,5-dihydroxypentyl nucleotide, 5'-5'-inverted abasic moiety;
• 1,4-butanediol phosphate;
• 5'-amino;
• and bridging or non bridging methylphosphonate and 5'-mercapto moieties, and wherein said 3'-cap structure is selected from the group consisting of 4'-thio nucleoside, carbocyclic nucleotide;
• 1,5-anhydrohexitol nucleotide;
• L-nucleotide;
• alpha-nucleotide;
• modified base nucleotide;
• threo-pentofuranosyl nucleotide;
• acyclic 3',4'-seco nucleotide;
• 3,4-dihydroxybutyl nucleotide;
• 3,5-dihydroxypentyl nucleotide;
• 3'-3'-inverted abasic moiety;
• 3'-2'-inverted nucleotide moiety;
• 3'-2'-inverted abasic moiety;
• 1,4-butanediol;
• hexylphosphate;
• aminohexyl phosphate;
• 3'-phosphate;
• and a bridging methylphosphonate moiety.