One hundred years of insulin research has led to many landmark discoveries, including the observation of a long-predicted conformational switch between the peptide hormone’s solution stable form and its bioactive conformation for receptor binding.1 Although receptor-bound and free insulin structures have been well characterized by X-ray crystallography2 and Cryo-EM,3 how the peptide undergoes the dynamic transition between these states remains unknown. Our research aims to investigate the potential role of insulin’s three disulfide bridges (A6-A11, A7-B7 and A20-B19) in influencing conformational change of the peptide structure between inactive and bioactive conformations. Replacing flexible native cystine linkages with structurally rigid and metabolically inert C-C motifs offers a library of bridging geometries through variable hybridization (sp3, sp2, sp), which can be used to probe the conformation required for bioactivity.4 This has been achieved to date with insulin’s A6-A11 intrachain disulfide bridge in which comparison between cis- and trans-alkene, and native bridge demonstrated a key conformational transition facilitated by bridge geometry.5 Interchain dicarba bridge replacement presents a significantly greater synthetic challenge, whilst retaining the added challenge of overcoming deleterious peptide aggregation, a common problem in insulin analogue synthesis. This requires the development of several new interconnected strategies to facilitate cross metathesis, including use of aggregation disrupting dehydroamino acid residues, preformed bridging motifs and protecting group free conditions. Development of a library of conformationally restricted analogues allows us to probe the structure function relationship of insulin and promote development of more efficient therapeutics.