Custom stereospecific phosphorothioate (PS) oligonucleotide synthesis with defined Rp/Sp stereochemical control for antisense, siRNA, and advanced oligo therapeutics.
Bio-Synthesis supports stereodefined, stereospecific, and stereopure oligonucleotide synthesis for programs where phosphorothioate chirality, backbone uniformity, and sequence-level control are important to development strategy.
Chiral oligonucleotide synthesis addresses the stereochemical complexity introduced by phosphorothioate (PS) linkages, where each phosphorothioate linkage introduces a chiral phosphorus center (Rp or Sp configuration). In conventional phosphorothioate oligo synthesis, these linkages are typically formed as mixed stereochemical populations, resulting in heterogeneous products.
Stereospecific oligo synthesis enables controlled formation of phosphorothioate linkages with defined stereochemistry, supporting programs that require greater molecular uniformity, structured backbone design, or sequence-specific stereochemical exploration.
Depending on program goals, this may include fully stereopure oligonucleotides, partially defined stereochemical patterns, or targeted stereochemical optimization at selected backbone positions. These approaches are relevant to antisense, siRNA, and other advanced oligonucleotide platforms where backbone design can influence overall behavior.
chiral backbone design platform
Flexible stereochemical design strategies for phosphorothioate oligonucleotides, from conventional mixed backbones to targeted stereodefined and fully stereopure constructs.
Stereopure
Defined backbone stereochemistry across the sequence
Patterned
Targeted Rp/Sp assignments at chosen positions
Conventional
Standard stereorandom phosphorothioate backbone population
Chiral oligonucleotide programs may be approached using fully stereopure, selectively patterned stereodefined, or conventional stereorandom phosphorothioate formats depending on design intent, development stage, and analytical goals.
Fully defined phosphorothioate stereochemistry across the backbone for programs requiring the highest degree of structural control.
Best fit
Programs prioritizing maximum stereochemical definition and sequence-level backbone control.
Discuss Stereopure Oligos →
Controlled stereochemistry at selected phosphorothioate positions to support focused structure-activity exploration.
Programs evaluating targeted Rp/Sp placement without requiring a fully stereopure backbone.
Discuss Patterned Designs →
Standard phosphorothioate oligonucleotides produced as mixed stereochemical populations for discovery and reference workflows.
Early discovery, reference comparisons, and programs where defined chirality is not required.
Compare with Stereopure →
This comparison highlights the main differences between stereopure, patterned stereodefined, and conventional stereorandom phosphorothioate oligonucleotides.
The most appropriate format depends on target biology, development stage, and whether defined phosphorothioate stereochemistry is part of the optimization strategy.
Program Support
We work with research teams to align stereochemical design strategy with sequence, modality, analytical scope, and development-stage goals.
Design Input
Sequence Review
Assess sequence context, modality, and stereochemical objectives.
Strategy
Format Selection
Compare stereopure, patterned, and conventional PS formats for fit.
Execution
Synthesis & Analysis
Support synthesis planning, purification, and fit-for-purpose analytics.
A typical stereospecific oligonucleotide project starts with defining the target biology and backbone design goal, followed by stereochemistry planning, synthesis, and analytical confirmation.
Confirm sequence, modality, application, and whether stereopure or patterned stereochemical control is desired.
Determine the level of Rp/Sp definition needed across the phosphorothioate backbone.
Execute synthesis, purification, and fit-for-purpose analytical confirmation aligned to the project goal.
Chiral backbone design can be relevant for antisense programs exploring backbone-dependent performance and sequence-specific optimization.
Defined phosphorothioate stereochemistry may be incorporated into selected RNA-targeting designs where backbone architecture is under active evaluation.
Useful for groups studying how controlled phosphorothioate stereochemistry affects oligonucleotide behavior across screening and optimization workflows.
Bio-Synthesis supports oligonucleotide programs with controlled project workflows, fit-for-purpose purification, and analytical review aligned to research and development requirements. For chiral oligonucleotide projects, emphasis is placed on clear backbone format definition, stereochemistry strategy alignment, and program-specific documentation.
For the fastest quote on chiral oligonucleotide synthesis, share your sequence, target application, desired stereochemistry strategy if known, scale, purity target, and any preferred comparison format.
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