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Screening of linolipins, i.e. galactolipids containing esterified residues of divinyl ether oxylipins, in the leaves of several higher plants revealed the presence of these complex oxylipins in the meadow buttercup leaves. The rapid accumulation of linolipins occurred in the injured leaves of meadow buttercup, while intact leaves possessed no linolipins. These oxylipins were isolated from the injured leaves, separated and purified by HPLC. The structural analyses of linolipins by UV, mass-spectroscopy and NMR spectroscopy resulted in the identification of eight molecular species. Three of them were identical to linolipins B-D found earlier in the leaves of flax (Linum usitatissimum L.). Other molecular species were identified as 1-O-(ω5Z)-etherolenoyl-2-O-dinor-(ω5Z)-etherolenoyl-3-O-β-D-galactopyranosyl-sn-glycerol, 1-O-(ω5Z)-etherolenoyl-2-O-(7Z,10Z,13Z)-hexadecatrienoyl-3-O-β-D-galactopyranosyl-sn-glycerol, 1-O-(ω5Z)-etherolenoyl-2-O-(7Z,10Z)-hexadecadienoyl-3-O-β-D-galactopyranosyl-sn-glycerol, 1-O-(ω5Z)-etherolenoyl-2-O-α-linolenoyl-3-O-β-D-galactopyranosyl-sn-glycerol, and 1-O-(ω5Z)-etherolenoyl-2-O-palmitoyl-3-O-(α-galactopyranosyl-1-6-β-D-galactopyranosyl)-sn-glycerol. The trivial names "linolipins E, F, G, H and I," respectively, have been ascribed to these novel complex oxylipins., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Five new heterocyclic compounds, 5-α-d-fructofuranosylmethyl-furfural (1), 5-β-d-fructofuranosylmethyl-furfural (2), 5-β-d-fructopyranosylmethyl-furfural (3), 4-(2-((2S-2,3-dihydroxypropoxy)methyl)-5-formyl-1H-pyrrol-1-yl)butanoic acid (4), and 3S,4S-4,5,8-trihydroxy-3-(prop-1-en-2-yl)isochroman-1-one (5), were obtained from the root of Ranunculus ternatus Thunb., which is a traditional Chinese anti-tuberculosis medicine. Their structures were elucidated by UV, IR, HRESIMS, NMR data, and the comparison of experimental and calculated electronic circular dichroism (ECD) spectra. Notably, compounds 1-3 are rarely occurring furfural fructosides in natural sources. These heterocyclic compounds could be further studied for the synthetic chemists and pharmacologists due to the source and structural properties., (Copyright © 2017 Elsevier Inc. All rights reserved.)