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Introduction: As inhibitors of advanced glycation end products (AGEs), such as pyridoxamine, significantly inhibit the development of retinopathy and neuropathy in rats with streptozotocin-induced diabetes, treatment with AGE inhibitors is believed to be a potential strategy for the prevention of aging, age- related diseases, and lifestyle-related diseases, including diabetic complications. In the present study, the MeOH extract of Epimedii Herba (EH; aerial parts of Epimedium spp.) was found to inhibit the formation of NE-(carboxymethyl)lysine (CML) and N"-(carboxymethyl) arginine (CMA) during the incubation of collagen- derived gelatin with ribose. Materials and methods: EH was purchased from Uchida Wakan-yaku Co., and a MeOH extract was prepared. Several steps of column chromatography purified the extract. Each fraction was tested for inhibitory activity by ELISA using monoclonal antibodies for CML and CMA. Results: After activity-guided fractionation and purification by column chromatography, three new prenylflavonoids [named Koreanoside L (1), Koreanoside E1 (2), and Koreanoside E2 (3)] and 40 known compounds (4-43) were isolated from EH, and their inhibitory effects against CML and CMA formation were tested. Among these, epimedokoreanin B (8), epimedonin E (21), epicornunin B (22), and epicornunin F (24) inhibited the formation of both CML and CMA, with epimedokoreanin B (8) having the most potent inhibitory effect among the isolated compounds. To obtain the structure-activity relationships of 8, the phenolic hydroxy groups of 8 were methylated by trimethylsilyl-diazomethane to afford the partially and completely methylated compounds of 8. Prenyl derivatives of propolis (artepillin C, baccharin, and drupanin) were used in the assay. Discussion: As only 8 showed significant activity among these compounds, the catechol group of the B ring and the two prenyl groups attached to the flavanone skeleton were essential for activity. These data suggest that 8 could prevent the clinical complications of diabetes and age-related diseases by inhibiting AGEs. [ABSTRACT FROM AUTHOR]

Two new resin glycosides, muricatins XII (1) and XIII (2), were isolated from the crude resin glycoside fraction of the seeds of Ipomoea muricata (L.) Jacq. (Convolvulaceae), along with three known ones, muricatins V (3), VI (4), and IX (5). Compounds 1 and 2 contained new glycosidic acids, muricatic acids E (1a) and F (2a), respectively. The structures of these compounds were determined using data obtained from spectroscopy measurements and chemical evidence. The results suggested that 1 and 2 have macrolactone structures (jalapins). Furthermore, the cytotoxic activity of the crude resin glycoside fraction and 3–5 against HL-60 human promyelocytic leukaemia cells was evaluated. All tested samples demonstrated cytotoxic activities. [ABSTRACT FROM AUTHOR]

In many languages there are words that behave like lexical verbs and on the one hand and like functional categories expressing distinctions of tense, aspect, modality, etc. on the other. The grammatical status of such words is frequently controversial; while some authors treat them as belonging to one and the same grammatical category, others assign them to different categories. The present paper is concerned with such a case of "doublets": Looking in more detail at the German item "drohen" "to threaten", it attempts to offer an account of the differences in the lexical and functional structure of this item by using grammaticalization theory as a framework. As the data presented in the paper suggest, this model in fact accounts for most though not for all of the properties characterizing the structure of the item. It is argued that in addition to synchronic analysis, a diachronic and comparative perspective is required in order to arrive at a more comprehensive understanding of the interface between lexical and functional structures. (Contains 8 tables.)

A new cholestane-type steroidal glycoside, solamyriaside A (1), was isolated from the fruits of Solanum myriacanthum Dunal (Solanaceae), along with two known steroidal glycosides, namely, solaviaside A (2) and aculeatiside A (3), and three known steroidal alkaloid glycosides, namely, solamargine (4), khasianine (5) and solasonine (6), which were isolated for the first time from this plant. Based on spectroscopic data as well as chemical evidence, 1 was determined to be 3-O-α-L-rhamnopyranosyl-(1→2)-O-[α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranosyl-22R,25R-cholest-5-ene-3β,16α,22,26-tetraol 26-O-β-D-glucopyranoside. The cytotoxic activity of 1–6 against HL-60 human promyelocytic leukaemia cells was examined. Compounds 4–6 showed cytotoxic activity. Among them, 4 exhibited the strongest activity with an IC50 value of 4.64 ± 0.17 μM, similar to the activity of cisplatin, a positive control. [ABSTRACT FROM AUTHOR]

Two new glycosidic acids, calyhedic acids E (1a) and F (2a), were isolated from the glycosidic acid fraction afforded by alkaline hydrolysis of the crude resin glycoside fraction obtained from whole plants of Calystegia hederacea Wall. Compounds 1a and 2a were characterised as 11S-hydroxyhexadecanoic acid 11-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-(1→3)-[O-α-L-rhamnopyranosyl-(1→2)]-O-β-D-glucopyranosyl-(1→2)-β-D-quinovopyranoside and an isomer of 1a, in which the 11S-hydroxyhexadecanoyl residue of 1a was replaced by a 12S-hydroxyhexadecanoyl residue, respectively, on the basis of spectroscopic data. [ABSTRACT FROM AUTHOR]