(Senior / Principal) Scientist, Organic Chemistry

The role

You will lead synthetic execution across small-molecule, peptide, and adjacent therapeutic programs. You will turn target structures into confirmed, test-ready compounds by choosing routes, solving reaction and purification problems, and building workflows.

What you will do

• Lead organic-chemistry execution from target-compound selection through route design, synthesis, purification, characterization, quality control, and biological handoff.
• Design and execute practical routes using solution-phase and solid-phase methods, functional-group transformations, coupling chemistry, protecting-group strategies, and late-stage diversification.
• Own the delivery of the right compounds with confirmed identity, purity, yield, documentation, and readiness for biological testing.
• Operate and help maintain key chemistry instrumentation, including HPLC, prep HPLC, LC-MS, microwave-assisted synthesis systems, and related platforms.
• Resolve difficult synthetic and analytical issues involving failed reactions, conversion, selectivity, side products, deprotection, solubility, purification, recovery, and instrument downtime.
• Work with biology and pharmacology teams to prioritize compounds using SAR, potency, stability, exposure, tolerability, and efficacy data.
• Improve routes, analytical methods, documentation, and laboratory workflows.

Required qualifications

• Five or more years of hands-on industry experience in synthetic organic, medicinal, peptide, or closely related chemistry
• Strong synthetic judgment and the ability to turn a target structure into a confirmed, biologically testable compound.
• Experience owning route selection, synthesis, purification, characterization, quality control, documentation, and biological handoff.
• Deep troubleshooting ability across reactions, purification, analytical methods, and laboratory instrumentation.
• Comfort working close to biological readouts while keeping primary ownership of practical chemistry execution.
• The ability to provide technical direction, improve team workflows, and remain directly involved in the hardest experiments.

Nice to have

• peptide experience is helpful but not required

Benefits

• $500+ monthly wellness budget for training, supplements, coaching, recovery, or other tools
• Medical, dental, and vision coverage options
• Capable covers 100% of the base policy
• Access to HSA, FSA, and 401K plans
• Healthy vegetarian dinners with the team are provided daily

Before you apply

• In-person on site work trial in San Francisco

About the company

Capable Labs is a mission-driven team in San Francisco. The team comprises members from MIT, Harvard Medical School, Roche, ETH, and Dana-Farber.