Related Experiment Video
Updated: Jun 25, 2026

Structure-Guided Design and Development of Novel Cyclophilin A Inhibitors and Ganoderiol-F Derivatives: An In-Silico Approach
Published on: June 23, 2026
Rational design and structural insights of osthole-derived selective AKR1C3 inhibitors with cellular activity
Xuehua Zheng1, Ping Huang1, Jing Mi1
1Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target & Clinical Pharmacology, the NMPA and State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences and the Affiliated Traditional Chinese Medicine Hospital, Guangzhou Medical University, Guangzhou 511436, China.
None:
Aldo-keto reductase 1C3 (AKR1C3) is a key enzyme in androgen biosynthesis and a crucial driver of castration-resistant prostate cancer (CRPC), making it a promising therapeutic target. Unintended inhibition of its homologous isoforms AKR1C1 and AKR1C2 may cause off-target effects and is therefore highly undesirable. In this study, we rationally designed selective AKR1C3 inhibitors derived from the natural product osthole by optimizing the C8- and C7-substituents to target the SP1 and SP2 pockets, respectively, thereby achieving high selectivity for AKR1C3. Among the compounds synthesized, eleven exhibited potent inhibition of AKR1C3 (IC₅₀ < 0.1 μM) with high selectivity over AKR1C1. Notably, compounds 7k and 7o demonstrated significant antiproliferative activity in 22Rv1 cells (IC₅₀ = 3.05 μM and 5.45 μM, respectively). Crystallographic analysis revealed that the coumarin core anchors to the oxyanion site, while the C8-substitute interacts with the SP1 pocket, enhancing both potency and selectivity. In contrast to other coumarin-based inhibitors, osthole-derived compounds with extended C8-substitutions, interact with the SP1 pocket in a novel and distinct manner. These findings validate our design strategy of enhancing SP1 pocket binding to improve AKR1C3 selectivity over other AKR1C isoforms, and provide valuable structural insights for the further development of selective AKR1C3 inhibitors as potential therapeutics for CRPC.
Related Concept Videos
Structure-Activity Relationships and Drug Design
SAR studies the intricate relationship between a drug's chemical structure and biological activity. It focuses on understanding how modifications to a drug's structure can influence its...
Adrenergic Agonists: Chemistry and Structure-Activity Relationship
Aromatic ring substitutions: Substituting the aromatic ring with –OH groups at positions 3 and 4 yields catecholamines (e.g., epinephrine), which have a high affinity for adrenoceptors. Hydrogen bonding between –OH groups and receptors enhances adrenergic activity.
Separation of the aromatic...
The Two-State Receptor Model
The binding affinity of a drug determines its interaction with one...
Drug-Receptor Interaction: Agonist
Agonists can bind to receptors in different ways. Some agonists bind directly to the receptor's active site, mimicking the endogenous ligand's action.
Drug-Receptor Interactions
Several parameters, such as the drug's affinity for its receptor and its efficacy, which is its ability to activate the receptor, determine the drug's effect on the tissue.
Dose-Response Relationship: Selectivity and Specificity
