Justicialosides A and B, two new flavone glycosides from the leaves of Ruspolia hypocrateriformis (Vahl) Milne-Redh. (Acanthaceae)

Abstract

Guetchueng, ST, Nahar, L, Ritchie, KJ, Ismail, FMD, Dempster, NM and Sarker, SD Justicialosides A and B, two new flavone glycosides from the leaves of Ruspolia hypocrateriformis (Vahl) Milne-Redh. (Acanthaceae) http://researchonline.ljmu.ac.uk/id/eprint/10483/ Article LJMU has developed LJMU Research Online for users to access the research output of the University more effectively. ABSTRACT Two new flavone glycosides, luteolin 7-O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside (1) and chrysoeriol 7-O-α-L-rhamnopyranosyl-(1→2)-β-D-xylopyranoside (2), along with five known compounds, luteolin 7-O-β-D-apiofuranosyl-(1→2)-β-D-xylopyranoside (3), grandulosides A and B (4 and 5), luteolin 7-O-[β-D-glucopyranosyl-(1→2)-α-L-rhamnosyl-(1→6)]-β-D-glucopyranoside (6) and 10H-quindoline (7) were isolated from the leaves of Ruspolia hypocrateriformis (Acanthaceae). Their structures were elucidated by spectroscopic means, including 1D and 2D NMR, HRESIMS and by comparison with published data.

Bioassay-Guided Isolation of New Flavonoid Glycosides from Platanus × acerifolia Leaves and Their Staphylococcus aureus Inhibitory Effects

“…Undoubtedly, the data above delineated a quercetin backbone [ 29 , 30 , 31 ]. In addition, the 1 H- 1 H COSY motif ( Figure 2 ) of H-1″/H-2″/H-3″/H-4″/H-5″/H 3 -6″ in conjunction with the 13 C ( Table 1 ) and HSQC NMR experiments ( Figure S3 ) revealed the presence of an α-rhamnose moiety [ 29 , 32 ], which was found to locate at C-3 due to the key HMBC correlation from H-1″ to C-3 (δ C 135.56) ( Figure 2 ). Besides, two p -coumarate units were constructed owing to the observation of two sets of well-resolved proton signals: δ H 7.47 (2H, br d, J = 8.4 Hz, H-2‴, 6‴), δ H 6.80 (2H, br d, J = 8.4 Hz, H-3‴, 5‴), δ H 7.61 (1H, d, J = 15.6 Hz, H-7‴), and δ H 6.31 (1H, d, J = 15.6 Hz, H-8‴) accounting for a (E)-p-coumarate unit; δ H 7.69 (2H, br d, J = 8.4 Hz, H-2′′′′, 6′′′′) and δ H 6.77 (2H, br d, J = 8.4 Hz, H-3′′′′, 5′′′′), together with δ H 6.88 (1H, d, J = 12.8 Hz, H-7′′′′) and δ H 5.73 (1H, d, J = 12.8 Hz, H-8′′′′), arising from a ( Z )- p -coumaryl moiety.…”

Haem polymerization inhibitory activity and cytotoxicity of six medicinal plants used in cameroon for the management of malaria

“…Ten cycles were completed for each successive solvent extraction. The extracts were filtered and evaporated to dryness using a rotary evaporator at a temperature not exceeding 40 °C and subsequently kept at 4°C until required 22 .…”

“…& Timler. They are used in Cameroonian traditional medicine for the treatment of different ailments including malaria and malaria symptoms including anaemia and fever (Table 1) [16][17][18][19][20][21][22] . The cytotoxic effects of the plants were also evaluated against three cancer cell lines.…”

Phenolic compounds from the leaves and stem bark of Pseudospondias microcarpa (A. Rich.) Engl. (Anacardiaceae)

“…(2) (Baldé et al, 1991), isovitexin (3) (Krafczyk et al, 2008), rhoifolin (4) (Osterdahl, 1979), quercetin 3-O-α-L-rhamnopyranoside (5) (Jiang et al, 2015), justicialoside A (6) (Guetchueng et al, 2019), granduloside A (7) (Tagousop et al, 2017), and pithecellobiumol B (8) (Wang et al, 2017) (Figure 1).…”