Scientist​/Senior Scientist, Medicinal Chemistry

About the Role

You’ll work closely with the founders and a small team from MIT, Harvard Medical School, Baker Lab, and Radical Numerics.

We are looking for speed and rigor, coupled with excitement, drive and a strong work ethic. In an early‑stage environment, we value people who can bring clarity to open‑ended problems, take ownership of the next steps, and follow through with energy.

Capable Labs is a place for ambitious, high‑integrity people who want to become dramatically better. You will be surrounded by people who care intensely about the work, get close feedback from the people making scientific and company‑defining decisions, and have room to own increasingly important problems.

We believe excellent work should be met with meaningful reward, ownership, and trust. Responsibility is earned through contribution, not title alone: anyone who demonstrates the judgment, rigor, and follow‑through to move important work forward can earn meaningful scope.

• Lead medicinal chemistry design and synthesis across small‑molecule, peptide, and peptide‑adjacent programs, from target compound selection through synthesis, purification, characterization, and handoff for biological testing.

• Design and execute synthetic routes using solid‑phase and solution‑phase workflows, including functional group transformations, coupling chemistry, protecting group strategies, late‑stage diversification, cleavage/deprotection where relevant, purification, and analytical characterization.

• Learn, operate, and help maintain key chemistry instrumentation, including HPLC/prep HPLC, LC‑MS, microwave‑assisted synthesis systems, and related analytical or purification platforms.

• Troubleshoot synthetic and analytical issues, including failed reactions, low conversion, poor selectivity, low crude purity, side products, solubility limitations, purification challenges, and instrument downtime.

• Interpret SAR, in vitro, and in vivo data to design next‑round compounds, using potency, selectivity, stability, exposure, tolerability, and efficacy data to guide priorities.

• You have 5+ years of hands‑on industry experience in medicinal or synthetic organic chemistry. Peptide experience is helpful, but not required.

• You have strong experimental judgment, deep troubleshooting ability, and a high bar for execution.

• You are comfortable owning chemistry end to end: compound design, route selection, synthesis, purification, characterization, QC, and preparation for biological testing.

• You work well close to the biological readout and use potency, efficacy, stability, exposure, and tolerability data to sharpen the next design cycle.

• You are proactive and reliable when issues arise. When a synthesis fails, an instrument is down, purity is low, or a handoff needs clarification, you help diagnose the issue, communicate clearly, and work toward a practical resolution.

• $145,000-$220,000 salary, plus equity options with an implied current value of approximately $50,000-$200,000 before exercise cost, taxes, dilution, and liquidity risk.

• Compensation will depend on the skills, experience, and scope of impact you bring. If your background, experience, or compensation needs fall outside this range, we are still open to a conversation based on the scope and impact you could bring.

• $500+ monthly wellness budget for training, supplements, coaching, recovery, or other tools that help you perform at your best.

• Healthcare:
  We offer a broad range of medical, dental, and vision coverage options, with Capable covering 100% of the base policy.

• You will also have access to HSA, FSA, and 401K plans.

• Healthy dinners with the team are provided daily.

• We support visa sponsorship where appropriate, including O‑1, H‑1B, J‑1, TN, and other employment‑based pathways. Our team is already international, with members from Canada, Pakistan, Germany, Austria, Switzerland, China, India, and the United States.