Steroidal 21-imidazolium salt derivatives: Synthesis and anticancer activity

Area of Science:

• Medicinal Chemistry
• Organic Synthesis
• Pharmacology

Background:

• Nitrogen-containing steroids are recognized for their role in prostate cancer therapy.
• Pregnane derivatives with an imidazolium moiety represent a novel class of potential therapeutics.

Purpose of the Study:

• To synthesize novel pregnane derivatives incorporating an imidazolium group.
• To evaluate the binding affinity of these compounds to human CYP17A1.
• To assess the antitumor activity of the synthesized steroids against various cancer cell lines.

Main Methods:

• Synthesis of pregnane derivatives from Δ16-20-ketones.
• Improved synthesis of the 20-keto-21-heterocycle-substituted fragment via epoxide rearrangement.
• Binding affinity analysis using human CYP17A1.
• Antitumor activity screening against prostate, solid, and hematologic cancer cell lines.

Main Results:

• A series of 21-imidazolium steroid derivatives were successfully synthesized.
• Binding affinity studies revealed type I interactions with human CYP17A1, with 16α,17α-epoxy-5α-pregnan-20-on-3β-ol showing the strongest affinity (Kd = 0.66 ± 0.05 µM).
• All imidazolium salts demonstrated activity against the LNCaP prostate cancer cell line. The intermediate 21-chloro-5α-pregn-16-en-20-on-3β-ol exhibited the most potent cytotoxicity against solid and hematologic cancer cell lines. Saturated derivatives were more cytotoxic than unsaturated ones.

Conclusions:

• The synthesized imidazolium-containing pregnane derivatives show promise as anticancer agents, particularly against prostate cancer.
• The study identified specific compounds with significant cytotoxic effects, warranting further investigation for therapeutic development.
• The synthetic methodology provides an efficient route to novel steroid-based anticancer drug candidates.