Quinoline alkaloids and friedelane-type triterpenes isolated from leaves and wood of Esenbeckia alata kunt (Rutaceae)

Abstract

This work describes the phytochemical exploration of the ethanol extract from leaves and wood of Esenbeckia alata, leading to the isolation and identification of quinoline alkaloids 4-methoxy-3-(3'-methyl-but-2'-enyl)-N-methyl-quinolin-2(1 H)-one, N-methylflindersine, dictamine, kokusaginine, Γ-fagarine, flindersiamine, as well as the fridelane-type triterpenes, frideline, fridelanol and its acetate derivative. Identification of these compounds was based on full analyses of spectroscopic data (¹H, 13C, 1D, 2D, IR, MS) and comparison with data reported in literature. Compound 4-methoxy-3-(3'-methyl-but-2'-enyl)-N-methyl-quinolin-2(1 H)-one is reported for the first time for the genus Esenbeckia

Bio-Guided Fractionation of Ethanol Extract of Leaves of Esenbeckia alata Kunt (Rutaceae) Led to the Isolation of Two Cytotoxic Quinoline Alkaloids: Evidence of Selectivity Against Leukemia Cells

“…The same previously reported extract from leaves of E. alata [11] was used for the present cytotoxicity-guided fractionation study. A portion of this primary ethanol extract (called EEa, 65 g) was fractionated by vacuum column chromatography (VCC) (80 × 8 cm) on silica gel using different solvents by increasing polarity, in order to have several fractions eluted with n -hexane (5.4 g), ethyl acetate (EtOAC) (2.3 g), methanol (MeOH) (25.6 g), and water (25.5 g).…”

“…Subfraction EA-EEa3 afforded 2 (135 mg) and EA-EEa6 yielded 1 (95 mg) as main compounds retaining the cytotoxic activity exhibited by extracts, fractions, and subfractions. These compounds were structurally elucidated by 1 H and 13 C-NMR (see Supplementary Materials) on comparing with authentic compounds previously isolated, whose structures are exposed in Figure 1 [11].…”

“…In particular, the aerial part of the medicinal shrub Esenbeckia alata is used as a febrifuge and insecticide in the Atlantic Coast of Colombia [9], promoting a particular interest for this plant. In previous phytochemical studies performed on E. alata , four metabolites (identified as 5-hydroxy-2-methylchromanone, (-)-episesamine, pellitonin, and sitosterol) were isolated from bark [9], whereas furanocoumarins, pyranocumarins, lignans, and quinoline alkaloids were obtained from leaves [10,11]. From this set of isolated metabolites, quinoline alkaloids are considered as taxonomic markers of the genus and they have been identified in several Esenbeckia plants [4,12,13,14,15].…”

Phytochemical Investigation of Alkaloids in the Iraqi Echinops heterophyllus (Compositae)

“…furacridone), an important subgroup of quinoline alkaloids. The plant family Rutaceae represents the major source of quinoline alkaloids.Some of these naturally occurring quinolines have profound medicinal properties while others have served as lead structures and provided inspiration for the design of synthetic quinolines as useful drugs (13) .…”

Phenolic Contents and Antioxidant Properties of Echinops ritro L. and E. tournefortii Jaup. Et. Spach Extract

“…Echinops plant was reported to possess variety of compounds belonging to various classes like: alkaloids, flavonoids, terpenoids, lipids, steroids and polyacetylenes [9]. Echinopsine was quinoline alkaloid isolated in 1900 by M. Greshoff from seeds of the blue globe thistle, E. ritro and its presence was also demonstrated in 14 other species of Echinops like E. latifolius, E. setifer [10]. Echinops species have been used as traditional medicine for treatment of migraine, diuretic, heart diseases, urinary infection, as well as worm and hemorrhoid in Ethiopia [11].…”