Synthesis of Phenanthridin-3-One Derivatives: Non-Steroidal Inhibitors of Steroid 5-Alpha-Reductase

The document from 1995 detailed the creation of new phenanthridin-3-one derivatives as inhibitors of the human steroid 5-α-reductase enzyme, which is involved in conditions like benign prostatic hyperplasia, androgenic alopecia, and acne. A six-step synthesis process was used, including a key cyclization step. Testing on the type 1 isozyme of 5-α-reductase showed that three derivatives had inhibition constants (Ki) of greater than 10 µM, 1.1 µM, and 0.92 µM, demonstrating that some were effective inhibitors, although they were less effective against the type 2 isozyme. The synthesis was highly efficient, and the results indicated that these compounds could be promising for treating androgen-related disorders.