. Author manuscript; available in PMC: 2014 Dec 20.

Published in final edited form as: J Org Chem. 2013 Dec 11;78(24):12690–12702. doi: 10.1021/jo4022937

Table 1.

T_m values of duplexes between B1–B6 and complementary DNA targets.^a

ON	Duplex	B =	ΔT_m/°C
ON	Duplex	B =	W	X	Y	Z
B1	5′-GTG BTA TGC		−0.5	+5.0	+11.0	+6.0
D2	3′-CAC TAT ACG		−0.5	+5.0	+11.0	+6.0

B2	5′-GTG ATB TGC		+0.5	+7.0	+14.0	+7.5
D2	3′-CAC TAT ACG		+0.5	+7.0	+14.0	+7.5

B3	5′-GTG BTB TGC		−1.0	+5.0	+13.5	+16.0
D2	3′-CAC TAT ACG		−1.0	+5.0	+13.5	+16.0

D1	5′-GTG ATA TGC		±0.0	+6.5	+11.5	+7.5
B4	3′-CAC TBT ACG		±0.0	+6.5	+11.5	+7.5

D1	5′-GTG ATA TGC		±0.0	+5.5	+12.0	+6.0
B5	3′-CAC TAT BCG		±0.0	+5.5	+12.0	+6.0

D1	5′-GTG ATA TGC		−2.0	+5.0	+13.5	+14.5
B6	3′-CAC TBT BCG		−2.0	+5.0	+13.5	+14.5

ΔT_m = change in T_m relative to unmodified reference duplex D1:D2 (T_m ≡ 27.5 °C); T_m’s determined as the maximum of the first derivative of melting curves (A₂₆₀ vs T) recorded in medium salt buffer ([Na⁺] = 110 mM, [Cl⁻] = 100 mM, pH 7.0 (NaH₂PO₄/Na₂HPO₄)), using 1.0 μM of each strand. T_m’s are averages of at least two measurements within 1.0 °C; A/C/G/T = adenin-9-yl/cytosin-1-yl/guanin-9-yl/thymin-1-yl DNA monomers. For structures of monomers W–Z, see Figure 1. Data for the B1/B2/B4/B5-series (for monomers X/Y/Z) have previously been reported in reference 12b.