Table 2: The 𝑇 𝑚 of the duplexes formed between modified (7X) or unmodified (7A) oligonucleotide and complementary 2′-O-methyl-RNA (or DNA) sequences bearing A, G, U (or T), or C nucleoside opposite to the artificial nucleoside 1 (in the case of oligonucleotide 7X) or adenosine (in the case of oligonucleotide 7A) in the presence and absence of Pd2+; [oligonucleotides] = 3.0 μM, [K2PdCl4] = 0/3.0 μM, I(NaClO4) = 0.1 M; pH = 7.4.

Complementary oligonucleotide   Sequence 𝑇 𝑚 /°C, duplex with 7X 𝑇 𝑚 /°C, duplex with 7A
(5′-GCGCXCCGG-3′)(5′-GCGCACCGG-3′)
Pd2+Pd2+
++

8U3′-CGCGUGGCC-5′ 6 0 . 6 ± 0 . 6 6 1 . 8 ± 0 . 4 7 3 . 7 ± 0 . 1 7 5 . 1 ± 0 . 3
8A3′-CGCGAGGCC-5′ 6 1 . 6 ± 0 . 1 6 1 . 4 ± 0 . 4 5 6 . 3 ± 0 . 1 5 6 . 3 ± 0 . 2
8G3′-CGCGGGGCC-5′ 6 0 . 1 ± 0 . 6 6 1 . 6 ± 0 . 3 6 0 . 4 ± 0 . 1 6 1 . 2 ± 0 . 3
8C3′-CGCGCGGCC-5′ 5 9 . 9 ± 0 . 4 6 0 . 7 ± 0 . 2 5 8 . 8 ± 0 . 2 5 9 . 0 ± 0 . 2
9U3′-CGCAUAGCC-5′ 6 0 . 4 ± 0 . 1 6 0 . 4 ± 0 . 3 2 7 . 6 ± 0 . 1 2 6 . 9 ± 0 . 3
9A3′-CGCAAAGCC-5′ 6 1 . 7 ± 0 . 9 6 1 . 0 ± 0 . 9 4 4 . 3 ± 0 . 6 4 3 . 6 ± 0 . 7
9G3′-CGCAGAGCC-5′ 6 0 . 1 ± 0 . 2 6 1 . 8 ± 0 . 4 4 3 . 5 ± 0 . 9 4 4 . 3 ± 0 . 3
9C3′-CGCACAGCC-5′ 6 1 . 1 ± 0 . 3 6 0 . 3 ± 0 . 5 4 3 . 9 ± 0 . 7 4 5 . 7 ± 0 . 8
10T3′-d(CGCGTGGCC)-5′ 6 2 . 6 ± 1 . 3 6 0 . 8 ± 0 . 2 4 9 . 5 ± 0 . 5 5 0 . 0 ± 0 . 1
10A3′-d(CGCGAGGCC)-5′ 5 9 . 1 ± 0 . 9 6 0 . 5 ± 0 . 5 4 3 . 5 ± 0 . 4 4 5 . 0 ± 0 . 3
10C3′-d(CGCGCGGCC)-5′ 6 0 . 7 ± 0 . 2 6 1 . 6 ± 0 . 1 4 5 . 5 ± 0 . 1 5 0 . 3 ± 0 . 2
10G3′-d(CGCGGGGCC)-5′ 5 8 . 6 ± 0 . 4 6 0 . 2 ± 0 . 2 4 0 . 8 ± 0 . 9 4 3 . 9 ± 0 . 5