New Acylated Flavonol Diglycosides of Cynanchum Acutum

Abstract

Three new acylated flavonol diglycosides that were characterized as quercetin 3- O-(6′”- O-E-isoferuloyl)-sophoroside (1), quercetin 3- O-(6′”- O-Z-isoferuloyl)-sophoroside (2) and quercetin 3- O-[2″- O-( E-6″′- O-isoferuloyl)-β-D-glucopyranosyl]-β-D-galactopyranoside (3), along with twelve known metabolites, have been isolated from the leaves of Cynanchum acutum L. The latter were identified as quercetin 3- O-β-D-neohesperidoside (4), rutin (5), quercetin 3- O-sophoroside (6), kaempferol 3- O-β-D-rutinoside (7), quercitrin (8), isoquercitrin (9), hyperin (10), guaijaverin (11), quercetin 7- O-β-D-glucopyranoside (12), quercetin (13), scopoletin (14) and ( E)-3-(3,4-dihydroxyphenyl)-propenoic acid (15). All metabolites have been isolated for the first time from the genus Cynanchum, except for 9 and 14. The structures were determined on the basis of chromatographic behavior, acid hydrolysis, chemical and physicochemical evidence (UV, HRESI-MS/MSn, 1H, 13C NMR, 1H-1H COSY, HSQC and HMBC). The chloroform extract and compounds 8 and 10 exhibited lethal effects towards brine shrimp, Artemia salina.

Cardenolides from Gomphocarpus sinaicus and Pergularia tomentosa (Apocynaceae: Asclepiadoideae) deter the feeding of Spodoptera littoralis

“…In the absence of cardenolides, the delayed larval development of S. littoralis on C. acutum might be due to latex produced as part of the induced defence against herbivory (for example, Rasmann et al 2009). However, the presence of flavonoid glycosides (Heneidak et al 2006;Fawzy et al 2008), acylated flavonol diglycosides (Mohamed et al 2008) or the flavonol aglycones that were detected in the methanol extract of C. acutum might explain both the delayed development observed by Broza and Sneh (1980) and the antifeedant activity of the methanol extract reported in this study.…”

Antioxidant and Anti-Inflammatory Activity of Cynanchum acutum L. Isolated Flavonoids Using Experimentally Induced Type 2 Diabetes Mellitus: Biological and In Silico Investigation for NF-κB Pathway/miR-146a Expression Modulation

“…Seven compounds ( Figure 1 ) were isolated and purified from the fractions of the crude extract of C. acutum . The compounds were identified as rutin 1 [ 41 ], quercetin-3- O -neohesperidoside 2 , quercetin-3- O - β -galactoside 3 [ 19 ], isoquercitrin 4 [ 41 ], quercetin 5 [ 41 ], kaempferol 3- O - β -glucoside 6 [ 42 ], and scopoletin 7 [ 20 ].The structures of the isolated compounds were elucidated based on spectroscopic data, and by comparison with data reported in the literature ( Supplementary Figures S1–S23 ).…”