Selective Formation of Ser-His Dipeptide via Phosphorus Activation.

The Ser-His dipeptide is the shortest active peptide. This dipeptide not only hydrolyzes proteins and DNA but also catalyzes the formation of peptides and phosphodiester bonds. As a potential candidate for the prototype of modern hydrolase, Ser-His has attracted increasing attention. To explore if Ser-His could be obtained efficiently in the prebiotic condition, we investigated the reactions of N-DIPP-Ser with His or other amino acids in an aqueous system. We observed that N-DIPP-Ser incubated with His can form Ser-His more efficiently than with other amino acids. A synergistic effect involving the two side chains of Ser and His is presumed to be the critical factor for the selectivity of this specific peptide formation.

Cascade Phosphinoylation/Cyclization/Isomerization Process for the Synthesis of 2-Phosphinoyl-9H-pyrrolo[1,2-a]indoles.

Pyrrolo[1,2-a]indole is a common structural motif found in many natural products and pharmaceuticals. A silver-mediated oxidative phosphinoylation of N-propargyl-substituted indoles was used to construct a variety of 2-phosphinoyl-9H-pyrrolo[1,2-a]indoles under mild conditions. This transformation offers a straightforward route to the formation of the C-P bond, cyclization, and isomerization in one step.