Prodrug Activation by Gold Artificial Metalloenzyme-Catalyzed Synthesis of Phenanthridinium Derivatives via Hydroamination

Angew Chem Int Ed Engl. 2021 May 25;60(22):12446-12454. doi: 10.1002/anie.202100369. Epub 2021 Apr 6.

Abstract

An emerging approach in the field of targeted drug delivery is the establishment of abiotic metal-triggered prodrug mechanisms that can control the release of bioactive drugs. Currently, the design of prodrugs that use abiotic metals as a trigger relies heavily on uncaging strategies. Here, we introduce a strategy based on the gold-catalyzed activation of a phenanthridinium-based prodrug via hydroamination under physiological conditions. To make the prodrug strategy biocompatible, a gold artificial metalloenzyme (ArM) based on human serum albumin, rather than the free gold metal complex, was used as a trigger for prodrug activation. The albumin-based gold ArM protected the catalytic activity of the bound gold metal even in the presence of up to 1 mM glutathione in vitro. The drug synthesized via the gold ArM exerted a therapeutic effect in cell-based assays, highlighting the potential usefulness of the gold ArM in anticancer applications.

Keywords: antitumor agents; gold catalysts; metalloenzymes; phenanthridinium; prodrugs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • A549 Cells
  • Amination
  • Catalysis
  • Cell Survival / drug effects
  • Cyclization
  • Glutathione / chemistry
  • Gold / chemistry*
  • Humans
  • Metalloproteins / chemistry
  • Metalloproteins / metabolism
  • Phenanthridines / chemistry*
  • Prodrugs / chemical synthesis
  • Prodrugs / chemistry*
  • Prodrugs / pharmacology
  • Serum Albumin / chemistry

Substances

  • Metalloproteins
  • Phenanthridines
  • Prodrugs
  • Serum Albumin
  • phenanthridinium
  • Gold
  • Glutathione