Synthesis, structure-activity relationship and binding mode analysis of 4-thiazolidinone derivatives as novel inhibitors of human dihydroorotate dehydrogenase

Design, synthesis, molecular modeling, and biological evaluation of acrylamide derivatives as potent inhibitors of human dihydroorotate dehydrogenase for the treatment of rheumatoid arthritis

Human dihydroorotate dehydrogenase (DHODH) is a viable target for the development of therapeutics to treat cancer and immunological diseases, such as rheumatoid arthritis (RA), psoriasis and multiple sclerosis (MS). Herein, a series of acrylamide-based novel DHODH inhibitors as potential RA treatment agents were designed and synthesized. 2-Acrylamidobenzoic acid analog 11 was identified as the lead compound for structure-activity relationship (SAR) studies. The replacement of the phenyl group with naphthyl moieties improved inhibitory activity significantly to double-digit nanomolar range. Further structure optimization revealed that an acrylamide with small hydrophobic groups (Me, Cl or Br) at the 2-position was preferred. Moreover, adding a fluoro atom at the 5-position of the benzoic acid enhanced the potency. The optimization efforts led to potent compounds 42 and 53‒55 with IC50 values of 41, 44, 32, and 42 nmol/L, respectively. The most potent compound 54 also displayed favorable pharmacokinetic (PK) profiles and encouraging in vivo anti-arthritic effects in a dose-dependent manner.

Structural Optimization and Structure-Activity Relationship of 4-Thiazolidinone Derivatives as Novel Inhibitors of Human Dihydroorotate Dehydrogenase

Human dihydroorotate dehydrogenase (hDHODH), one of the attractive targets for the development of immunosuppressive drugs, is also a potential target of anticancer drugs and anti-leukemic drugs. The development of promising hDHODH inhibitors is in high demand. Based on the unique binding mode of our previous reported 4-thiazolidinone derivatives, via molecular docking method, three new series 4-thiazolidinone derivatives were designed and synthesized as hDHODH inhibitors. The preliminary structure–activity relationship was investigated. Compound 9 of biphenyl series and compound 37 of amide series displayed IC₅₀ values of 1.32 μM and 1.45 μM, respectively. This research will provide valuable reference for the research of new structures of hDHODH inhibitors.

Design, synthesis, and nematicidal activities of novel 1,3-thiazin(thiazol)-4-one derivatives against Meloidogyne incognita

Four series of novel 1,3-thiazin(thiazol)-4-one derivatives were synthesized by Suzuki coupling. Preliminary bioassays showed that most of the synthesized compounds exhibited good inhibitory activity in vivo against root-knot nematodes, Meloidogyne spp. at 20 mg L−1. Among the tested compounds, we found that two compounds displayed 46.4% and 41.4% inhibitory activity even at 1 mg L−1, respectively.

Catalyst-free synthesis of thiazolidines via sequential hydrolysis/rearrangement reactions of 5-arylidenethiazolidin-4-ones at room temperature

Functionalized thiazolidines were obtained via the rearrangement reactions of 5-arylidenethiazolidin-4-ones at room temperature.