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The Antioxidant and Tyrosinase-inhibiting Activities of 8-O-4′ N eolignans from Crataegus pinnatifida Seeds

Xiao-Xiao Huang, Qing-Bo Liu, Le Zhou, Sen Liu, Zhuo-Yang Cheng, Qian Sun, Ling-Zhi Li and Shao-Jiang Song

School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Key Laboratory of Structure-Based, Drug Design & Discovery, (Ministry of Education), Shenyang 110016, Liaoning, P. R. China

Abstract: Many tyrosinase inhibitors have been alleged to have serious side effects. To search for relatively mild and safe tyrosinase inhibitors, two new 8-O-4′ neolignans, named huangnin A (1) and B (2), and four known analogs (3-6) were isolated from the seeds of Crataegus pinnatifida. Their structures were elucidated by spectroscopic analyses (1D, 2D NMR, HRESIMS, CD and Rh 2(OCOCF 3) 4-induced CD). In addition, the in vitro antioxidant and anti-tyrosinase activities of all isolates were evaluated. The results showed that compound 5 has good antioxidant and promising tyrosinase-inhibiting activities.

Keywords: Crataegus pinnatifida; Rosaceae; 8-O-4′ neolignans; antioxidant activity; tyrosinase-inhibiting activity. © 2015 ACG Publications. All rights reserved.