Lead Peptide Medicinal Chemist Radiopharma

Mariana Oncology, Inc.; Watertown (MA); On-site; USD 109,000 - 202,000; Full time

Job summary

Mariana Oncology, Inc. seeks a Principal Scientist I, Medicinal Chemistry to join our Discovery Chemistry team. You will lead design and synthesis of peptide-based radiopharmaceuticals, guiding hit-to-candidate workstreams and serving as a technical and strategic leader.

You will mentor junior scientists, manage external CROs, and collaborate with biology, radiochemistry, DMPK, and pharmacology to advance programs, while ensuring safety and timely delivery.

Qualifications

• PhD in Organic Chemistry or Medicinal Chemistry with 0–3 years industry experience, or BS/MS in Chemistry with 6+ years.
• Demonstrated expertise in peptide medicinal chemistry and peptide synthesis.
• Strong understanding of drug discovery principles, medicinal chemistry, structure-based drug design, and synthetic organic chemistry.
• Proven ability to independently solve complex scientific challenges and develop creative, practical solutions.
• Experience managing external CROs and scientific collaborations.
• Demonstrated ability to influence project direction, build productive cross-functional relationships, and thrive in a collaborative environment.
• Excellent communication, organizational, and scientific writing skills with strong attention to detail.

Responsibilities

• Lead medicinal chemistry design and synthesis activities from hit identification through lead optimization and candidate selection.
• Serve as a hands-on contributor, executing multi-step peptide syntheses to support radiopharmaceutical discovery programs.
• Provide scientific leadership and operational oversight for peptide synthesis laboratory activities.
• Serve as an internal subject matter expert in peptide chemistry, driving problem-solving efforts and advising project teams.
• Mentor and provide technical guidance to junior scientists, co-ops, and interns.
• Manage external CRO relationships to ensure timely execution of chemistry objectives.
• Collaborate with cross-functional teams, including biology, radiochemistry, DMPK, and pharmacology, to advance discovery programs.
• Derive insights from chemistry, affinity, pharmacology, and DMPK datasets to inform strategy.
• Present project updates and scientific findings to project teams and leadership.
• Maintain accurate electronic laboratory notebook records and ensure compliance with safety requirements.
• Partner with Development colleagues to transfer synthetic methods and analytical procedures.
• Deliver high-quality results while managing priorities and timelines.

Skills

Peptide medicinal chemistry

Peptide synthesis

CRO management

Collaborative teamwork

Scientific writing

Communication

Education

PhD in Organic Chemistry or Medicinal Chemistry

BS/MS in Chemistry with 6+ years industry experience

Job description

Mariana Oncology, Inc. seeks a Principal Scientist I, Medicinal Chemistry to join our Discovery Chemistry team. You will lead design and synthesis of peptide-based radiopharmaceuticals, guiding hit-to-candidate workstreams and serving as a technical and strategic leader.

You will mentor junior scientists, manage external CROs, and collaborate with biology, radiochemistry, DMPK, and pharmacology to advance programs, while ensuring safety and timely delivery.