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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.

Four new resin glycosides with macrolactone structures (jalapins), namely, calyhedins VII ( 1 )-X ( 4 ), were isolated from the rhizomes of Calystegia hederacea Wall. (Convolvulaceae). The structures of 1 - 4 were determined based on spectroscopic data. They were classified into three ring types: a 27-membered ring ( 1 ), a 22-membered ring ( 2 , 3 ), and a 23-membered ring ( 4 ). Their sugar moieties were partially acylated using five organic acids, including ( E )-2-methylbut-2-enoic acid, 2 S -methylbutyric acid, and 2  R -methyl-3 R -hydroxybutyric acid. Compound 4 was the first genuine resin glycoside with calyhedic acid F as the glycosidic acid component. Additionally, the cytotoxic activities of 1 , 2 , and 4 towards HL-60 human promyelocytic leukaemia cells were evaluated. All compounds demonstrated almost the same activity as the positive control, cisplatin.

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-22 R ,25 R -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 IC 50 value of 4.64 ± 0.17 μM, similar to the activity of cisplatin, a positive control.

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 11 S -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 11 S -hydroxyhexadecanoyl residue of 1a was replaced by a 12 S -hydroxyhexadecanoyl residue, respectively, on the basis of spectroscopic data.

Kabosu ( Citrus sphaerocarpa Hort. ex Tanaka) fruits have pleasant and fresh odors and have been used as raw materials for vinegar, seasonings, jams, marmalades and juices in Japan. The n -butanol extracts from kabosu fruits were prepared and a component in the extract was purified by column chromatography and HPLC to afford compounds 1 - 3 . Three compounds, 5-(hydroxymethyl)-2-furaldehyde ( 1 ), umbelliferone ( 2 ) and oxypeucedanin hydrate ( 3 ), have been isolated from kabosu, and the structures of compounds 1 - 3 were elucidated by 1   D and 2   D NMR as well as EI-MS. Compound 2 exhibited potent glutaminase inhibitory activity with an IC 50 value of 1.33   mM. This is the first report on glutaminase inhibitory activity of 2 and the isolation of three compounds 1 - 3 from kabosu fruits.

Two new oleanane-type triterpenoids with an epoxy bridge between C-3 and C-25, named lantacamaric acids A and B, were isolated from the leaves and stems of Lantana camara L. (Verbenaceae). In addition, seven known triterpenoids, two known iridoid glycosides, four known phenylethanoid glycosides, one known flavonoid glycoside, and one known cyanogenic glycoside were isolated. Their structures were determined based on the spectroscopic data. Furthermore, the cytotoxic activities of the isolated triterpenoids toward HL-60 cells were examined. The IC 50 values of all compounds were obtained and ranged from 1.16 to 68.4 μM, with three compounds exhibiting stronger activities than the positive control, cisplatin. In addition, the structure-activity relationship was investigated.

A new resin glycoside, named calysolin XVIII (1), was isolated from the leaves, stems and roots of Calystegia soldanella Roem. et Schult. (Convolvulaceae). The structure of 1 was defined as 11S-jalapinolic acid 11-O-β-d-glucopyranosyl-(1 → 3)-O-(2-O-2S-methylbutyryl,4-O-3-hydroxy-2-methylenebutyryl)-α-l-rhamnopyranosyl-(1 → 2)-[O-β-d-glucopyranosyl-(1 → 6)-O-(34-di-O-2S-methylbutyryl)-β-d-glucopyranosyl-(1 → 3)]-O-β-d-glucopyranosyl-(1 → 2)-β-d-quinovopyranoside, intramolecular 1,2″'″'-ester on the basis of spectroscopic data. Compound 1 is the first known resin glycoside to feature 3-hydroxy-2-methylenebutyric acid as a component organic acid. In addition, 1 demonstrated an antiviral activity against herpes simplex virus type 1, with an IC 50 value 2.3 μM.

Two new ursane-type triterpenoids (1, 2) attached to isopropylidenedioxy group were isolated from the seeds of blackberry (Rubus fructicosus L., Rosaceae) along with two known ursane-type triterpenoids, 2,3-O-isopropylidenyl-2α,3α,19α-trihydroxyurs-12-en-28-oic acid (3) and 1β-hydroxyeuscaphic acid (4). The chemical structures of 1 and 2 were determined to be 2,3-O-isopropylidene-1β,2β,3β,19α-tetrahydroxyurs-12-en-28-oic acid and 1,2-O-isopropylidene-1β,2α,3α,19α-tetrahydroxyurs-12-en-28-oic acid, respectively, based on spectroscopic data. Additionally, their cytotoxic activity towards HL-60 human leukaemia cells was evaluated. Among them, 3 demonstrated a clear cytotoxic activity with 72.8 μM of IC50 value.

A new triterpenoid glycoside (1) was isolated from the methanol extract of the leaves and stems of Duranta repens L. (Verbenaceae) along with 14 known compounds consisting of eight triterpenoids, four iridoids, one phenylethanoid glycoside and one flavonoid. The chemical structure of 1 was determined to be bayogenin 3-O-[β-D-glucopyranoside]-28-O-[α-L-rhamnopyranosyl-(1→5)-O-β-D-apiofuranosyl-(1→4)-O-α-L-rhamnopyranosyl-(1→2)-O-α-L-arabinopyranosyl] ester, based on spectroscopic data. In addition, the inhibitory effects of the isolates on lipoxygenase activity were examined. Among them, acteoside and apigenin resulted in 94 ± 3.6% and 82 ± 4.7% inhibition, respectively, at 0.5 mM.