Synthesis of A11 Cys -B11 Cys Disulfide Surrogates of H2 Relaxin through an Intermolecular Native Chemical Ligation-Assisted Diaminodiacid Strategy.

We report an intermolecular native chemical ligation-assisted diaminodiacid strategy for the flexible construction of A11 Cys -B11 Cys disulfide surrogates of H2 relaxin. The practicality of this strategy was evidenced by the synthesis of four new H2 relaxin analogs, among which H2-2a-B28 Ile is found to exhibit improved potency, selectivity, and stability compared with native H2 relaxin.