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One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (2, 3 isolated from C. magnus; 4–7, 10 and 11 isolated from Myrsine latifolia; 4, 8 and 9 isolated from Myrsine sessiflora; 6, 7, 10, 12 and 13 isolated from Myrsine congesta). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of Grevillea robusta. Since resorcinols are known to exhibit strong cytotoxic activity, compounds 1 and 2 were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity in vitro and compounds 3–13 were tested for their antileishmanial activity. Compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all tested cell lines. Compounds 3–13 were not active against Leishmania amazonensis amastigotes. One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds (2–13), isolated from four plants belonging to Myrsinaceae family. Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. Among the tested molecules, only compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all cell lines tested. [ABSTRACT FROM AUTHOR]

The water-soluble blue-green pigment marennine, produced and partly excreted by the diatom Haslea ostrearia , and known for a long time for its role in the greening of oysters, was isolated from the culture medium, purified, and analyzed by Nuclear Magnetic Resonance (NMR) in order to gain insight into its chemical structure. The spectra show mainly carbohydrates of a complex composition, apparently highly branched, and with a mass in the order of 10 kDa. There are, in addition, some signals of aliphatic and, much weaker, aromatic groups that present aglycons. The latter might be responsible for the color. These carbohydrates are always associated with the blue-green color and cannot be separated from it by most treatments; they are interpreted as constituting the frame of the pigment. NMR after hydrolysis identifies the most abundant monosaccharides in marennine as galactose, xylose, mannose, rhamnose, and fucose.

Eleven compounds were isolated from Poraqueiba sericea stems and identified as niga-ichigoside-F1 (1), trachelosperoside B1 (2), 4-epi-niga-ichigoside (7), 19α-hydroxyasiatic acid (3), myrianthic acid (4), hyptatic acid (5), trachelosperogenin B (6), arjunolic acid (8), and trachelosperogenin E (9), secologanoside (10) and secoxyloganin (11). Compounds 1-11 were tested for their antileishmanial activities against Leishmania infantum promastigotes, 1-6 and 8-11 were tested for their cytotoxic activities on fibroblasts, 1-3, 5-6, 8-11 were evaluated for their anti-elastase and anti-acetylcholinesterase assays activities by a spectrophotometric method and 1-2, 5 and 7-10 were tested using bioautography for their β-glucosidase. No antileishmanial activity was detected; compounds 1, 2 and 11 showed a moderate cytotoxic activity with IC 50 17.7, 20.5 and 10.9 μg/mL, respectively; compounds 2, 8, 9 and 10 gave a percentage of inhibition ranging from 13 to 16% (at 50 μg/mL) and compounds 1 and 2 showed an inhibition zone on β-glucosidase and anti-acetylcholinesterase assays.

Twelve oleanane saponins, zebiriosides A-L, were isolated from the roots of Dendrobangia boliviana Rusby, together with two known saponins, talunùmoside I and 3-O-β-d-glucuronopyranosyl serjanic acid. These saponins are glycosides of serjanic or phytolaccinic acid. Their structures were established on two basis: first, their spectral data, mainly HR-TOFESIMS, 1D-NMR ((1)H, (13)C, DEPT) and 2D-NMR ((1)H(1)H COSY, TOCSY, HSQC, HMBC, and ROESY), and second by comparison with literature data. These compounds were evaluated for their cytotoxic, antileishmanial and hemolytic activities. No antileishmanial or hemolytic activities were revealed, however zebirioside C and zebirioside I showed cytotoxicity against fibroblasts with IC50 of 6.4 and 5.6 μM, respectively., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The asymmetric unit of the title compound, (C(6)H(4)S(4))(8)[Mo(6)O(19)](2)·CH(3)CN, contains two halves of two centrosymmetric [Mo(6)O(19)](2-) hexa-molybdate anions, which are each built up from six distorted MoO(6) octa-hedra sharing common edges and one common vertex at the central O atom, six tetra-thia-fulvalene cations (three of which are located on mirror planes) to balance the charge and a half of an acetonitrile solvent mol-ecule, likewise located on a mirror plane. The two central hexa-molybdate O atoms occupy special positions 2a and 2d, respectively. The cations and anions are inter-linked through C-H⋯O contacts.

The structure of the title compound, NH(4)(C(8)H(20)N)(3)[Mo(8)O(26)], is built up by discrete cations and anions, with two formula units in the asymmetric unit. The β-octa-molybdate anions are linked to the ammonium cations via N-H⋯O hydrogen bonding involving terminal oxide groups and to the tetra-ethyl-ammonium cations via weak C-H⋯O inter-actions.