Table 1.
Properties of 2′-carboxy-modified 2′-O-methyloligonucleotides and their conjugates
| # | Oligonucleotide sequence, 5′-3′/conjugated molecule | MALDI-TOF MS calc./found m/z) | Retention timea/min | Yield b (%) |
|---|---|---|---|---|
| I | UUUUUU*UUUU | 3183.9/3182.6 | 15.5 | – |
| II | CUCCCAGGCU*CA | 3942.6/3942.7 | 15.7 | – |
| I.7 | N, N, N-Tris(aminoethyl)amine (7) | 3311.6/3310.2 | 14.5 | >90 |
| I.8 | Cyclohexylamine (8) | 3264.6/3264.1 | 16.0 | >90 |
| I.9 | 3-Amino-1,2-propanediol (9) | 3256.5/3254.8 | 15.0 | >90 |
| I,10 | Histamine (10) | 3276.5/3277.8 | 14.8 | 75 |
| I.11 | Spermine (11) | 3367.7/3366.6 | 14.7 | 85 |
| I.12 | N, N, N′, N′-Tetrakis(3-aminopropyl)-1,4-butanediamine (12) | 3481.8/3482.6 | 14.9 | 80 |
| II.13 | 1-Aminopyrene (13) | 4141.8/4138.4 | 27.1 | 65 |
| II.14 | 1-Pyrenemethylamine (14) | 4155.9/4153.4 | 27.5 | 85 |
| II.15 | H-Phe-NH215) | 4088.8/4084.3 | 17.2 | >90 |
| II.16 | H-Leu-NH2 (16) | 4054.8/4051.0 | 16.2 | >90 |
| II.17 | H-Phe-Phe-NH2 (17) | 4235.9/4230.4 | 21.6 | >90 |
| II.18 | H-Leu-Phe-NH2 (18) | 4201.9/4199.4 | 16.9 | >90 |
| II.19 | H-Gly-Leu-Met-NH2 (19) | 4243.0/4245.8 | 17.1 | >90 |
| II.20 | H-Pro-Leu-Gly-NH2 (20) | 4208.9/4206.3 | 21.7 | 75 |
| II.21 | H-Asn-Arg-Asn-Phe-Leu-Arg-Phe-NH2 (21) | 488.7/4894.0 | 21.5 | 80 |
a
For conditions, see Experimental section.
b
Conversion of oligonucleotide peak to the conjugate peak, calculated from RP-HPLC traces.