Vitellaroside, A New Cerebroside from Vitellaria paradoxa (Sapotaceae) and its Bioactivities

Abstract

A new cerebroside (2R)-2-hydroxy-N-[(Z,2S,3S,4R)-1-O-β-D-glucopyranosyl-3,4-dihydroxynonadec-8-en-2-yl] nonacosanamide (1) was isolated from the wood of roots of V. paradoxa along with six known compounds including catechin (2), quercetin (3), spinasterol 3-O-β-D-glucopyranoside (6), gallic acid (7) and a mixture of β-sitosterol (4) and stigmasterol (5). The structure of the new compound was established by 1D (1 H and 13 C NMR) and 2D NMR (COSY and HSQC) spectroscopy, extensive mass spectrometry and by comparison with published data. The antibacterial, α-glucosidase and alkaline phosphatase (AP) inhibitory activities of all the pure compounds were evaluated. The antibacterial activities were evaluated against three gram negative bacteria (Escherichia coli; Salmonella typhimurium and Pseudomonas aeruginosa) while APs inhibitory activities were evaluated on h-TNAP and h-IAP. Significant antibacterial activity was recorded for quercetin (3) against P. aeruginosa. Most of the compounds except 1 and 6 were found to be inhibitors of α-glucosidase. The highest inhibitory potential being recorded for quercetin (3) with IC 50 value of 4.30 ± 0.01 µM, 55 fold higher than the standard drug acarbose (IC 50 =234.6 ± 2.01 µM). All tested compounds exhibited moderate inhibitory activities against APs. h-TNAP inhibitory values were ranged between 41.24 ± 1.33 µM and 312.54 ± 6.44 µM while h-IAP inhibitory values were in the range of 47.95 ± 0.35 µM and 777.47 ± 18.55 µM. Quercetin (3) was found to be the most active h-IAP inhibitor (IC 50 =47.95 ± 0.35 mM), whereas, spinasterol 3-O-β-D-glucopyranoside (6) was found to be the most active h-TNAP inhibitor (IC 50 =41.24 ± 1.33 mM). The new compound (1) showed moderate inhibition on h-IAP (78.11 ± 3.70 µM) and on h-TNAP (88.84 ± 2.70 µM).

α-Glucosidase Inhibitory Activity of Cycloartane-Type Triterpenes Isolated from Indonesian Stingless Bee Propolis and Their Structure–Activity Relationship

“…Some α-glucosidase inhibitors, such as acarbose and voglibose, which were originally obtained from natural sources by fermentation, can effectively control blood glucose levels after food intake and have been used clinically in the treatment of diabetes mellitus [6]. However, their synthesis involves complicated multistep procedures.…”

A New Cytotoxic Ceramide from Dalbergia boehmii Taub. Stem Bark

“…As expected, instead the characteristic signals of secondary amide group, the 13 C NMR spectrum of compound 1 exhibited two carbon signals at δ C 130.8 and 130.7 corresponding to a double bond, with a trans configuration, that was determined by the chemical shifts of its allylic carbon atoms appearing at δ C 32.9 and 33.3. [17,18] This double bond was located in the fatty acid moiety at C-15ʹ by EI-MS analysis. Signals of an oxymethylene at δ C 62.1 and three oxymethines at δ C 76.8, 73.1 and 72.5 were also visible.…”

“…[17] Thus, according to the 13 C NMR data of compound 1, the relative stereochemistries of C-2 (δ C 53.0), C-3 (δ C 76.8), and C-4 (δ C 73.1), were found to be 2S, 3S, and 4R. [17,18] From the above analysis the structure of compound 1 was set as (2ʹR, 15ʹE)-2ʹ-hydroxy-N-[(2S,3S,4R)-1,3,4trihydroxyhenicosan-2-yl]eicos-15ʹ-enamide named dalbergiamide. The new compound dalbergiamide (1) and the triterpene olean-12ene-3,11-dione (2) were tested for their cytotoxic activities against MCF-7 cells.…”

Two new sphingolipids from the stem bark of Synsepalum msolo (Sapotaceae)

“…These ingredients are used and found effective as sweeteners, anti-infections and anti-bacterials [ 7 ]. For instance, the stem bark, roots and leaves of Synsepalum msolo contain terpenoids (taraxeryl acetate, taraxerol, herranone, and betulinic acid), steroids (spinaterol and spinasterol-3-O- β -D glucopyranoside) and phenols (catechin, epicatechin and myricitrin) reported in numerous studies to demonstrate anticancer, anti HIV, antibacterial, antimalarial, analgesic, anti-inflammatory, antioxidant, anti-viral, and anti-allergenic activities [ [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] ]. Other classes of compounds isolated from this plant includes, saponins (pachystelanosides A and B) and sphingolipid (pachysteloside A) (b) , [13] , (a) .…”