Glycol Synthesis Lab Report

Rose Bengal-(bis(aminoethyl)ethylene glycol) (2) from Rose Bengal disodium salt (1)
The synthesis was done following procedure from [15]. Rose Bengal Na+ salt (915 mg, 0.90 mmol) was dissolved in DMF (2ml) and DIPEA (0.312 ml, 1.80 mmol), HATU (308 mg, 0.81 mmol) were added. After activation for 15 min, the mixture was added to O-Bis-(aminoethyl)ethylene glycol trityl resin (309 mg, 0.31 mmol) preswollen in DMF for 2 hours. The coupling reaction wrapped in aluminum foil was allowed to proceed overnight on a nitrogen bubbler apparatus. The resulting red-burgundy coloured resin was filtered and washed well with DMF. The resin was treated with 20% piperidine in DMF to hydrolyze any unwanted acylation on the phenolic hydroxyl groups. The resin

The solution was stirred at room temperature for 8h. The solvent was blown out with nitrogen. The residue was added to 1 ml of water containing 0.1% TFA and purified on RP-HPLC. Massspec of the final product clearly indicates presence of RB modified on PEI by series of peaks matching different polymer compositions (see Fig. 6).

RP-HPLC program:
0-5 min
5-30 min
30-35 min
20% MeCN
20-85% MeCN
85-99% MeCN

5-{3-(3-N-polyethyleniminemaleimide)propylamidophenyl}-10,15,20-tris(4-sulfonato-phenyl)porphyrin trisodium salt (TPPS-PEI) (8b)
TPPS-Mal (20 mM) in 500 μL of dry DMF was titrated to 500 μL of 40 mM polyethylenimine in dry DMF. After stirring at room temperature for 8 h additional 0.5 ml of 40 mM PEI were added. The solution mixture was kept with stirring overnight. The solvent was removed under reducing