Antisense pro-drugs: 5'-ester oligodeoxynucleotides

Area of Science:

• Oligonucleotide synthesis
• Medicinal chemistry
• Drug delivery

Background:

• Lipophilic oligonucleotides offer potential as antisense pro-drugs due to improved cellular uptake.
• The ester bond linkage for lipophilic modification is susceptible to degradation during standard oligonucleotide deprotection methods.

Purpose of the Study:

• To develop a robust synthesis strategy for 5 eal-ester oligonucleotides resistant to deprotection conditions.
• To enable the efficient production of lipophilic oligodeoxynucleotides for potential therapeutic applications.

Main Methods:

• Utilized base-labile tert-butylphenoxyacetyl amino protecting groups (t-BPA).
• Employed an oxalyl-controlled pore glass (CPG) anchor group.
• Developed a novel deprotection protocol using ethanolamine (EA) instead of aqueous ammonia.

Main Results:

• Successfully synthesized 5 eal-palmitoyl oligodeoxynucleotides with good yields.
• Demonstrated the stability of the 5 eal-ester linkage under the new deprotection conditions.
• Overcame the lability issues associated with traditional oligonucleotide synthesis.

Conclusions:

• The developed method provides a reliable route for synthesizing 5 eal-ester modified oligonucleotides.
• This advancement facilitates the creation of novel antisense pro-drugs with enhanced delivery capabilities.
• The combination of t-BPA protecting groups, oxalyl-CPG anchor, and EA deprotection is effective for lipophilic oligonucleotide synthesis.