An oligomeric compound comprising at least one monomer of Formula II: wherein independently for each monomer of Formula II: Bx is a heterocyclic base moiety selected from adenine, guanine, thymine, cytosine, uracil and 5-methylcytosine; A is O; T 4 is an internucleoside linking group linking the monomer to the oligomeric compound, wherein each internucleoside linking group is, independently, a phosphodiester internucleoside linking group or phosphorothioate internucleoside linking group; and T 3 is a phosphorus moiety having the formula: wherein: R a and R c are each, independently, OH, SH, C 1 -C 6 alkyl, substituted C 1 -C 6 alkyl, C 1 -C 6 alkoxy, substituted C 1 -C 6 alkoxy, amino or substituted amino; and R b is O or S; each Q 1 is H and each Q 2 is methyl; or each Q 2 is H and each Q 1 is methyl; G 1 is selected from OCH 3 , OCH 2 F, OCHF 2 , OCF 3 , OCH 2 CH 3 , O(CH 2 ) 2 F, OCH 2 CHF 2 , OCH 2 CF 3 , OCH 2 -CH=CH 2 , O(CH 2 ) 2 -OCH 3 , O(CH 2 ) 2 -SCH 3 , O(CH 2 ) 2 -OCF 3 , O(CH 2 ) 3 -N(R 4 )(R 5 ), O(CH 2 ) 2 -ON(R 4 )(R 5 ), O(CH 2 ) 2 -O(CH 2 ) 2 -N(R 4 )(R 5 ), OCH 2 C(=O)-N(R 4 )(R 5 ), OCH 2 C(=O)-N(R 6 )-(CH 2 ) 2 -N(R 4 )(R 5 ) or O(CH 2 ) 2 -N(R 6 )-C(=NR 7 )[N(R 4 )(R 5 )] wherein R 4 , R 5 , R 6 and R 7 are each, independently, H or C 1 -C 6 alkyl; each substituted group comprises one or more optionally protected substituent groups independently selected from halogen, OJ 1 , N(J 1 )(J 2 ), =NJ 1 , SJ 1 , N 3 , CN, OC(=L)J 1 , OC(=L)N(J 1 )(J 2 ) and C(=L)N(J 1 )(J 2 ); L is O, S or NJ 3 ; each J 1 , J 2 and J 3 is, independently, H or C 1 -C 6 alkyl; and wherein said oligomeric compound comprises from 8 to 40 monomeric subunits, is complementary to a target RNA and is capable of activating argonaute protein. Bx is a heterocyclic base moiety selected from adenine, guanine, thymine, cytosine, uracil and 5-methylcytosine; A is O; T 4 is an internucleoside linking group linking the monomer to the oligomeric compound, wherein each internucleoside linking group is, independently, a phosphodiester internucleoside linking group or phosphorothioate internucleoside linking group; and T 3 is a phosphorus moiety having the formula: wherein: R a and R c are each, independently, OH, SH, C 1 -C 6 alkyl, substituted C 1 -C 6 alkyl, C 1 -C 6 alkoxy, substituted C 1 -C 6 alkoxy, amino or substituted amino; and R b is O or S; R a and R c are each, independently, OH, SH, C 1 -C 6 alkyl, substituted C 1 -C 6 alkyl, C 1 -C 6 alkoxy, substituted C 1 -C 6 alkoxy, amino or substituted amino; and R b is O or S; each Q 1 is H and each Q 2 is methyl; or each Q 2 is H and each Q 1 is methyl; G 1 is selected from OCH 3 , OCH 2 F, OCHF 2 , OCF 3 , OCH 2 CH 3 , O(CH 2 ) 2 F, OCH 2 CHF 2 , OCH 2 CF 3 , OCH 2 -CH=CH 2 , O(CH 2 ) 2 -OCH 3 , O(CH 2 ) 2 -SCH 3 , O(CH 2 ) 2 -OCF 3 , O(CH 2 ) 3 -N(R 4 )(R 5 ), O(CH 2 ) 2 -ON(R 4 )(R 5 ), O(CH 2 ) 2 -O(CH 2 ) 2 -N(R 4 )(R 5 ), OCH 2 C(=O)-N(R 4 )(R 5 ), OCH 2 C(=O)-N(R 6 )-(CH 2 ) 2 -N(R 4 )(R 5 ) or O(CH 2 ) 2 -N(R 6 )-C(=NR 7 )[N(R 4 )(R 5 )] wherein R 4 , R 5 , R 6 and R 7 are each, independently, H or C 1 -C 6 alkyl; each substituted group comprises one or more optionally protected substituent groups independently selected from halogen, OJ 1 , N(J 1 )(J 2 ), =NJ 1 , SJ 1 , N 3 , CN, OC(=L)J 1 , OC(=L)N(J 1 )(J 2 ) and C(=L)N(J 1 )(J 2 ); L is O, S or NJ 3 ; each J 1 , J 2 and J 3 is, independently, H or C 1 -C 6 alkyl; and wherein said oligomeric compound comprises from 8 to 40 monomeric subunits, is complementary to a target RNA and is capable of activating argonaute protein. <EOS>