Biocatalytic Steroidal 9α-Hydroxylation and Fragmentation Enable the Concise Chemoenzymatic Synthesis of 9,10-Secosteroids

Angew Chem Int Ed Engl. 2024 Apr 15;63(16):e202319624. doi: 10.1002/anie.202319624. Epub 2024 Mar 11.

Abstract

9,10-Secosteroids are an important group of marine steroids with diverse biological activities. Herein, we report a chemoenzymatic strategy for the concise, modular, and scalable synthesis of ten naturally occurring 9,10-secosteroids from readily available steroids in three to eight steps. The key feature lies in utilizing a Rieske oxygenase-like 3-ketosteroid 9α-hydroxylase (KSH) as the biocatalyst to achieve efficient C9-C10 bond cleavage and A-ring aromatization of tetracyclic steroids through 9α-hydroxylation and fragmentation. With synthesized 9,10-secosteroides, structure-activity relationship was evaluated based on bioassays in terms of previously unexplored anti-infective activity. This study provides experimental evidence to support the hypothesis that the biosynthetic pathway through which 9,10-secosteroids are formed in nature shares a similar 9α-hydroxylation and fragmentation cascade. In addition to the development of a biomimetic approach for 9,10-secosteroid synthesis, this study highlights the great potential of chemoenzymatic strategies in chemical synthesis.

Keywords: 9,10-Secosteroid; Biocatalysis; Biological activity; Chemoenzymatic synthesis; Rieske oxygenase-like 3-ketosteroid 9α-hydroxylase (KSH).

MeSH terms

  • Bacterial Proteins / metabolism
  • Hydroxylation
  • Mixed Function Oxygenases / metabolism
  • Secosteroids*
  • Steroids / chemistry

Substances

  • Secosteroids
  • Bacterial Proteins
  • Steroids
  • Mixed Function Oxygenases