Synthesis of Polycyclic γ-Lactams by Ni(0)-Catalyzed [2+2+1] Cycloaddition of Imines and
3-[2-(5-Aryl-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)thiazol-4-yl]-4hydroxy-6-methyl-2H-pyran-2-ones 6a-h were synthesized via the ring closure reactions of 3-phenyl-5-aryl-4,5-dihydropyrazole-1-carbothioamides 3a-h with 3-(bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one 5.The new synthesized thiazolyl-pyrazolinyl-pyran-2-one compounds were evaluated for their potential antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical method.The molecular docking of the synthesized compounds on DPPH oxidase protein showed a high binding affinity, confirming the experimental results recorded.The synthesized compounds deserve a consideration for further analyses regarding the control of oxidative stress and their use as possible antioxidant agents in the pharmaceutical industry.
From the peels of Citrus sphaerocarpa, two new limonoids, sphaerocarpain Ⅰ and Ⅱ were isolated together with five known compounds including methyl deacetylnomilinate and ichangin.The chemical structures of the new compounds were elucidated based on chemical/physicochemical evidence.For sphaerocarpain Ⅰ and Ⅱ, the absolute configuration was established by comparison of experimental and predicted electronic circular dichroism (ECD) data.Among the isolated compounds, sphaerocarpain I, II, methyl deacetylnomilinate and ichangin showed cytotoxic activity against both human neuroblastoma cells (SH-SY5Y) and human glioblastoma cells (U-251 MG).
