Associate Scientist, Peptide Chemistry

About The Role We are a vibrant and intensely mission-driven team in San Francisco, comprising members from MIT, Harvard Medical School, Roche, ETH, and Dana-Farber. About The Role We are a vibrant and intensely mission-driven team in San Francisco, comprising members from MIT, Harvard Medical School, Roche, ETH, and Dana-Farber. We value 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. What You’ll Do Execute end-to-end peptide synthesis workflows, including resin loading, coupling and deprotection cycles, cleavage, purification, analytical characterization, and sample preparation for testing. Run microwave-assisted solid-phase peptide synthesis, support routine synthesizer maintenance, and help troubleshoot failed couplings, low crude purity, side products, cleavage issues, and instrument downtime. Purify and characterize peptide candidates using analytical HPLC, prep HPLC, LC-MS, and related methods; record identity, purity, yield, and batch-level QC data before handoff. Prepare compounds for in vitro and in vivo testing, maintain accurate experimental records, and communicate synthesis results, issues, and timelines clearly to the team. Support next-round compound design by sharing synthesis feasibility, purity, yield, stability, and analytical observations from each batch. Who You Are You have hands-on chemistry experience and strong experimental taste. You may come from any education background; what matters is that you can learn fast and care about the quality of the result. You’re excited to own synthesis end-to-end: designing compounds, running reactions, purifying and characterizing them, and preparing them for testing with care and urgency. You enjoy solving problems creatively, iterate fast, and keep the science rigorous. You like being close to the biological readout. You want to understand how compounds perform in vitro and in vivo, then use potency and efficacy data to inform the next design cycle. You have high agency. When an instrument breaks, a synthesis fails, or a handoff is unclear, you take ownership and troubleshoot quickly. Pay & Benefits $90,000-$140,000 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. #J-18808-Ljbffr Capable