Alnuheptanoid B: A new Cyclic Diarylheptanoid from Alnus japonica Stem Bark

Sabrin R.M. Ibrahim, Gamal A. Mohamed, Amgad I. M. Khedr and Bader M. Aljaeid

Department of Pharmacognosy and Pharmaceutical Chemistry, College of Pharmacy, Taibah University, Al Madinah Al Munawarah 30078, Saudi Arabia

Department of Pharmacognosy, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt 3Department of Natural Products and Alternative Medicine, Faculty of Pharmacy, King Abdulaziz University, Jeddah, 21589, Saudi Arabia

Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Assiut Branch, Assiut 71524, Egypt

Department of Pharmacognosy, Faculty of Pharmacy, Port Said University, Port Said 42526, Egypt

Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia

Abstract: A new cyclic diarylheptanoid namely alnuheptanoid B (3), along with four known cyclic diarylheptanoids: myricanone (1), (+)-S-myricanol (2), myricanone 5-O- b -D-glucopyranoside (4), and (+)-S-myricanol 5-O- b -D-glucopyranoside (5) were isolated from Alnus japonica Steud (Betulaceae) stem bark. Their structures were determined by spectroscopic analyses, including UV, IR, 1D ( 1H and 13C), 2D (COSY, HMQC, and HMBC), and HRESIMS, as well as optical rotation measurement. Compounds 1, 2, 4, and 5 are reported for the first time from the plant. All isolated compounds 1-5 were tested for their antioxidant and anti-inflammatory activities using DPPH assay and carrageenin induced rat paw edema model, respectively. They displayed significant antioxidant activity in relation to propyl gallate (positive control). Compound 2 demonstrated anti-inflammatory effect at a dose 10 mg/kg.

Keywords:Alnus japonica; Betulaceae; alnuheptanoid B; cyclic diarylheptanoid; antioxidant; anti-inflammatory . © 2015 ACG Publications. All rights reserved.