Acylated flavonol glycosides and terpenoids from the leaves of Alibertia sessilis

Abstract

Dois novos flavonóis glicosilados, juntamente com iridóides, triterpenóides, esteróides e tocoferolquinona, foram isolados das folhas de Alibertia sessilis (Rubiaceae). As estruturas dos flavonóides foram determinadas através de métodos espectroscópicos, principalmente da RMN de 13 C e de 1 H. Two novel acylated flavonol glycosides, along with iridoids, triterpenes, ste roids and α-tocopherolquinone, were iso lated from the leaves of Alibertia sessilis (Rubiaceae). The deter mi na tion of the struc tures of the new com pounds was based mainly on 1 Hand 13 C-NMR.

Antioxidant, antimicrobial activities of flavonoids glycoside from Leucaena leucocephala leaves

“…1). data was in agreement with the published data (Olea, et al, 1997). Compounds 2-8 were isolated for the first time from L. leucocephala leaves and were identified as quercetin-3-O-α-rhamnopyranosyl-(1'''→2'') -β-glucopyranoside(2), Quercetin -7-O-α-rhamnopyranosyl-(1'''→2'') -β-glucopyranoside (3),quercetin-3 -O-α-rhamnopyranoside(4), quercetin-3-O-β-glucopyranoside(5) isovitexin (6) vitexin (7) and quercetin(8) according to spectral data that were identical to those previously published (Agrawal 1989;Markham and Geiger 1994).…”

Secondary Metabolites from Rubiaceae Species

“…Regarding the distribution of the major secondary metabolites in Rubiaceae, indole alkaloids are indicated as the main chemical markers of this family [42][43][44][45][46]. Iridoids, anthraquinones, triterpene glycosides, flavonoids, lignoids, terpenes and phenols derivatives, were also reported [47].…”

A Novel Multifunctional Compound Camellikaempferoside B Decreases Aβ Production, Interferes with Aβ Aggregation, and Prohibits Aβ-Mediated Neurotoxicity and Neuroinflammation

“…Its UV spectrum exhibited two characteristic flavonol absorption bands at 314 and 268 nm (Fig. S1) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 5 rhamnopyranosyl [δ H 5.540 (1H, br s) and 1.135 (3H, d, J = 6.2 Hz), δ C 98.12 (C-Rha2-1), 70.19 (C-Rha2-2), 70.31 (C-Rha2-3), 71.75 (C-Rha2-4), 73.91 (C-Rha2-5), and 17.71 (C-Rha2-6)] 18 (Table S1, Figs. S4-S7).…”

“…Many BACE1 inhibitors were reported to have potential application in AD treatment, with some currently under investigation in clinical trials 19 . To inhibit Aβ aggregation, decrease aggregate formation, and attenuate Aβ cytotoxicity, numerous inhibitors including antibodies, peptides, and synthetic and natural compounds have been tested, but only a few agents are suitable for clinical trials 18,20 . Moreover, many therapeutic efforts have aimed to inhibit Aβ-induced glial inflammation and oxidative stress; some agents show effective therapeutic potential for AD treatment in vitro and in vivo 21,22 .…”