New Thymoquinol Glycosides and Neuroprotective Dibenzocyclooctane Lignans from the Rattan Stems of Schisandra chinensis

Abstract

Three new lignans (1 - 3), together with four new thymoquinol glycosides (4 - 7), were isolated from 70%-EtOH extract of the rattan stems of Schisandra chinensis. The structures of 1 - 7 were elucidated by detailed spectroscopic analyses, and these new compounds were identified as pinobatol-9-O-β-d-glucopyranoside (1), 1,2,13,14-tetramethoxydibenzocyclooctadiene 3,12-O-β-d-diglucopyranoside (2), 3,7-dihydroxy-1,2,13,14-tetramethoxydibenzocyclooctadiene 12-O-β-d-glucopyranoside (3), thymoquinol 2-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside (4), thymoquinol 2-O-α-d-arabinofuranosyl-(1→6)-β-d-glucopyranoside (5), thymoquinol 5-O-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside (6), and thymoquinol 5-O-α-d-arabinofuranosyl-(1→6)-β-d-glucopyranoside (7). The neuroprotective activity of 1 - 7 was evaluated on PC12 cells with neurotoxicity induced by amyloid-beta 1 - 42 (Aβ ). Compounds 2 and 3 showed protecting activity against Aβ-induced toxicity in PC12 cells.

Plant Adaptogens—History and Future Perspectives

“…All of phytochemicals determined beneficial effects such as: cytotoxic, antioxidant, neuroprotective, hepatoprotective, increased physical strength, stress-protective, anti-inflammatory [ 12 , 88 , 104 ]. The adaptogenic effect of Schisandra chinensis is associated with the antioxidant effect and the influence on the hypothalamic-pituitary-adrenal axis by lowering the level of corticotropin-releasing hormone [ 29 , 76 ].…”

Lignans and Terpenoids from the Leaves of Schisandra chinensis

“…According to the HMBCs from H‐1′ to C‐6′′ and from H‐1′′ to C‐2, we confirmed that two sugar residues were connected by 1→6 glycosidic bond and d ‐glucose was linked to C‐2. Compared the 1D NMR data of 2 with literatures, compound 2 was similar to thymoquinol 2‐ O ‐ β ‐ d ‐apiofuranosyl‐(1→6)‐ β ‐ d ‐glucopyranoside . The obvious difference was that a hydroxy group in thymoquinol 2‐ O ‐ β ‐ d ‐apiofuranosyl‐(1→6)‐ β ‐ d ‐glucopyranoside was replaced by a methoxy group at C‐5 in compound 2 , which supported by HMBCs from MeO ( δ H 3.76, s) to C‐5.…”

Phenolic Constituents from Fallopia multiflora (Thunberg) Haraldson

“…Analysis of the 13 C NMR and HSQC spectra of 1 revealed the presence of an aromatic methyl at δ C 20.2 (3-CH 3 ), an acetyl group (δ C 208.2 and 32.6) and ten aromatic signals of a naphthalene skeleton (Table 1). In addition, an apiofuranosyl-(1→6)-glucopyranoside moiety was recognized [5]. Acid hydrolysis and GC analysis led to the identification of D-glucose and D-apiose.…”