Anti-inflammatory and Neurotrophic 2H-1-Benzopyran Derivatives of Chaenomeles sinensis

 Two 2 H -1-benzopyran derivatives, methyl 8-hydroxy-2,2-dimethyl-2 H -1-benzopyran-5-carboxylate ( 1 ) and methyl 8-hydroxy-2,2-dimethyl-2 H -1-benzopyran-6-carboxylate ( 2 ), including a new compound ( 1 ) were isolated from the twigs of Chaenomeles sinensis . Their chemical structures were characterized based on analysis of NMR data including 1 H and 13 C, COSY, HSQC, and HMBC and HRMS data. The isolated compounds ( 1 and 2 ) were assessed for their anti-neuroinflammatory activity by measuring inhibition levels of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells and for their neurotrophic activity by the secretion of nerve growth factor (NGF) in C6 cells. Compounds 1 and 2 exhibited powerful anti-neuroinflammatory effects with IC 50 values of 17.14 and 19.30 μ M, respectively, without cell toxicity, and also showed moderate effects on the stimulation of NGF secretion levels with 113.15 ± 3.54 and 130.20 ± 8.03%, respectively. The biosynthetic pathway of 1 and 2 was proposed that they would be derived from a protocatechuic acid and an isoprenyl unit.