Chemistry of Natural Compounds最新文献

One previously undescribed benzenoid analogue, 19F0006 (1), together with two known ones, methyl vanillate (2) and indole-3-aldehyde (3) were isolated from the mycelial EtOAc extracts of soil-derived fungus Trichoderma longicollum BCRC 19F0006. The structures of all the isolates were elucidated on the basis of extensive analyses of spectroscopic data and comparison with literature data.

A series of N′-aryldenehydrazide derivatives from isopimaric acid were designed, synthesized, and evaluated for their anticancer activities. Some synthesized compounds showed stronger anticancer activity than the positive control drug 5-fluorouracil (5-FU). Compound 3c, with a hydroxyl and a methoxyl in the benzene, exhibited the strongest cytotoxicity against human malignant melanoma cells (A375) and ovarian carcinoma cells (ES-2), with IC₅₀ values of 9.54 and 5.43 μM, respectively. It also demonstrated reduced toxicity to normal human hepatocytes (L-O2), making it the most promising anticancer candidate. Structure–activity relationship studies revealed that the introduction of the hydroxyl group into the benzene ring is beneficial to improve the antitumor activity.

A synthetic method for water-soluble conjugates of chlorin e₆ carboxyl derivatives with diacetone galactose is proposed. Studies of a primary assessment of the dark and photoinduced cytotoxicity showed that the obtained digalactose carboxychlorins were promising for further studies as potential photosensitizers for medical application.

Our ongoing phytochemical investigation on the twigs and leaves of Euphorbia fischeriana led to the isolation of one new alkylresorcinol dimer, fiseuphenol (1), along with four known flavones (2–5) and three coumarins (6–8). Their structures were identified on the basis of extensive spectroscopic data, including NMR as well as HR-ESI-MS. Compound 1 was the first example of an alkylresorcinol dimer from the Euphorbiaceae plants.

A new dimeric chromanone (1), together with ten known compounds (2–11), was isolated from the endophytic fungus Pleospora sp. BMX18 derived from healthy branches of Aquilaria sinensis. The structure of the new compound (1) was elucidated by extensive spectroscopic analyses, including high-resolution electron spray ionization mass spectrometry and nuclear magnetic resonance. Its absolute structure was assigned by analysis of CD spectrum. Compounds 8, 10, and 11 showed moderate antibacterial activities against Aeromonas hydrophila, Vibrio owensii, Vibrio alginolyticus, and Aeromonas veronii.

Thirteen known (1–13) and a previously undescribed diarylheptanoid 14, named cis-oregonoyl A, were isolated from Alnus incana bark using standard dry column flash silica gel chromatography followed by reversed-phase semipreparative HPLC. Structure elucidation was performed on the basis of ¹H and ¹³C, COSY, NOESY, HSQC, and HMBC NMR experiments, supported with HR-ESI-MS, IR, and UV spectroscopy. The known diarylheptanoids and their derivatives are as follows: aceroside VII (1), 1,7-bis-(3,4-dihydroxyphenyl)-3-hydroxyheptane-5-O-β-D-xylopyranoside (2), platyphyllenone (3), alusenone A (4), alusenone B (5), hirsutenone (6), platyphylloside (7), platyphyllonol-5-O-β-D-xylopyranoside (8), alnuside A (9), alnuside B (10), oregonin (11), oregonoyl A (12), and oregonoyl B (13). Compounds 1, 3–6, 8, 12–14 have not been detected before in A. incana. From a comparison of diarylheptanoid profiles of Alnus species growing in Serbia, A. incana, A. glutinosa and A. viridis, revealed high similarity between A. incana and A. glutinosa.

Cyclocondensation reactions of homoveratrylamine and acetoacetic ester with several aromatic aldehydes were studied. The reactions formed a mixture of derivatives of 5-N-[(3,4-dimethoxyphenylethyl)amino]-2,4-diethylester of 1-methyl-3-aryl-cyclohexen-4-ol-1, diethyl 4-hydroxy-4-methyl-6-oxo-2-aryl-cyclohexane-1,3-dicarboxylate, and an imine.

A new pyrrolidine alkaloid, lobelialsine (1), has been isolated from the aerial part of Lobelia alsinoides subsp. hancei, together with eight known compounds, lobelanidine (2), lobeline (3), luteolin (4), apigenin (5), naringenin (6), hesperetin (7), scoparone (8), and isoscopoletin (9). The structure of the new compound 1 was determined through spectroscopic and MS analyses. Among the isolated compounds, lobelialsin (1), luteolin (4), apigenin (5), and naringenin (6) showed potent inhibition with IC₅₀ values of 18.31 ± 1.34, 17.49 ± 1.06, 15.49 ± 0.94, and 25.47 ± 1.83 μM, respectively, against LPS-induced NO generation. In addition, compounds 1, 4, 5, and 6 also showed potent DPPH radicals scavenging activities with SC₅₀ values of 27.92 ± 2.17, 12.28 ± 0.69, 38.63 ± 2.75, and 55.01 ± 4.80 μM, respectively.

Lipids from seeds of Ammodendron conollyi Bunge ex Boiss. were studied for the first time. The content, group composition, and classes of lipids (% of dry substance) were established as 15.0% neutral lipids (NL), 1.2% polar lipids (PL), 1.0% phospholipids, and quinolizidine alkaloids in PL. Fatty acids of the lipids were represented by 18–21 components. Unsaturated acids in NL and PL were dominated by 18:1 and 18:2; saturated acids in PL, by 16:0. The composition of lipophilic substances (LS), with phytosterols accounting for 49.8%, was determined. The exogenic effect of NL from seeds on the growth of wheat and cucumber sprouts was studied under normal conditions and with salt stress. Growth-stimulatory activity at concentrations of 0.001 and 0.0001% was found.

A novel piperidine alkaloid, named (7′E)-3-acetyl-1-olefinic-3′,5′-dihydroxymethylphenyl-4′-O-prenylpiperidine alkaloid (1), and six known piperidine alkaloids (2–7) were isolated from highland barley Monascus purpureus for the first time. These compounds 1–7 were determined by extensive and comprehensive spectral analyses and comparing with their references. Compounds (1–7) were assayed for their inhibitory effects against the increases in ALT and AST levels on H₂O₂-induced HepG2 cells. As a result, compounds 1, 2, and 4 displayed significant hepatoprotective activities.