Discovery and In Vivo Efficacy of AZ-PRMT5i-1, a Novel PRMT5 Inhibitor with High MTA Cooperativity.

PRMT5, a type 2 arginine methyltransferase, has a critical role in regulating cell growth and survival in cancer. With the aim of developing MTA-cooperative PRMT5 inhibitors suitable for MTAP-deficient cancers, herein we report our efforts to develop novel "MTA-cooperative" compounds identified through a high-throughput biochemical screening approach. Optimization of hits was achieved through structure-based design with a focus on improvement of oral drug-like properties. Bioisosteric replacement of the original thiazole guanidine headgroup, spirocyclization of the isoindolinone amide scaffold to both configurationally and conformationally lock the bioactive form, and fine-tuning of the potency, MTA cooperativity, and DMPK properties through specific substitutions of the azaindole headgroup were conducted. We have identified an orally available in vivo lead compound, 28 ("AZ-PRMT5i-1"), which shows sub-10 nM PRMT5 cell potency, >50-fold MTA cooperativity, suitable DMPK properties for oral dosing, and significant PRMT5-driven in vivo efficacy in several MTAP-deficient preclinical cancer models.

[Studies on chemical constituentsfrom leaves of Acer truncatum].

OBJECTIVE: To study the chemical constituents from the leaves of Acer truncatum. METHOD: Various chromatographic techniques were used to isolate and purify the constituents. The structures of these compounds were elucidated on the basis of spectral analysis. RESULT: Seven compounds were isolated and identified as p-sitosterol (1), beta-amyrin (2), beta-amyrin acetate (3), 3, 5-dihydroxy-4-methoxybenzoic acid (4), astragalin (5), quercetin-3-O-beta-D-galactoside (6), and quercetin-3-O-alpha-L-rhamnoside (7). CONCLUSION: All of compounds were isolated from this plant for the first time.