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.

The pace and scope of the work create a substantial opportunity for growth. We are looking for speed and rigor, coupled with excitement and drive. 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.

We believe excellent performance and excellent output should be met with meaningful reward and ownership. At Capable, that means anyone who proves they can drive work forward can lead important programs, from senior scientists to junior scientists.

What You’ll Do

• 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.

Who You Are

• 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.

Pay & Benefits

• $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 for the role will depend on a number of factors, including a candidate’s qualifications, skills, competencies, and experience.

• We sponsor visas, if necessary.

• Wellness budget: $500 per month to spend on training, supplements, personal trainers, and everything you need to become your best self.

• Healthcare. We offer a range of comprehensive medical options, so you can choose the plan that best fits your needs.

Application Process

• Initial application

• First phone screen

• Second phone screen, approximately 30 minutes

• In-person work trial in San Francisco

Apply Today

Applying takes 5 minutes and we encourage you to apply as soon as possible. We're evaluating candidates on a rolling basis and want to make an offer quickly.