Three Novel Triterpenoid Dienolides from Phyllanthus myrtifolius

Three novel pentacyclic triterpenoid dienolides, phyllenolide A (=3β‐acetoxyglutina‐5(10), 6‐dien‐27,8α‐olide; 1 ), phyllenolide B (=3β‐(benzoyloxy)glutina‐5(10),6‐dien‐27,8α‐olide; 2 ), and phyllenolide C (=3β‐(2‐hydroxybenzoyloxy)glutina‐5(10),6‐dien‐27,8α‐olide; 3 ), were isolated from the aerial parts of Phyllanthus myrtifolius Moon . (Euphorbiaceae). These three compounds possess an endocyclic γ‐lactone moiety across ring C and a homo‐annular diene system in ring B. Their structures were established by analyses of CD, NOED, and 2D‐NMR spectra.     

Constituents of the Whole Herb of Clinoponium laxiflorum

The isolation and identification of twenty‐two components (including one new compound) from the whole herb of Clinoponium laxiflorum (Hay) Matsum (Labiatae) are described. Their structures were determined on the basis of spectral and chemical transformation. One new compound is methyl rosmarinate. The other twenty‐one compounds include three steroids (α‐spinasterol, α‐spinasteryl‐3‐O‐β‐D‐glucopyranoside, and β‐sitosteryl‐3‐O‐β‐glucopyranoside), three triterpenes (oleanolic acid, ursolic acid, and betulinic acid), nine flavonoids (didymin, apigenin‐7‐O‐β‐glucopyranoside, luteolin‐7‐O‐β‐glucopyranoside, isosakuranetin, narigenin, apigenin, luteolin, narirutin, and hesperidin), three lignolic acids (rosmarinic acid, 3‐(3,4‐dihydroxyphenyl)lactic acid, and caffeic acid), and three phenols (4‐hydroxybenzaldehyde, 3,4‐dihydroxybenzaldehyde, and 3,4‐dihydroxybenzoic acid).     

Flavonoid Glycosides from Terminalia catappa L.

Under the inhibition of Cu⁺²‐induced LDL oxidation‐guided fractionation, two new flavone glycosides with galloyl substitution were isolated from the dried fallen leaves of Terminalia catappa L. Their structures were established as apigenin 6‐C‐(2″‐O‐galloyl)‐β‐D‐glucopyranoside ( 1 ) and apigenin 8‐C‐(2″‐O‐galloyl)‐β‐D‐glucopyranoside ( 2 ), together with four known flavone glycosides, isovitexin, vitexin, isoorientin, and rutin, on the basis of spectroscopic method. Compounds 1 and 2 showed significant antioxidative effects. Their IC₅₀ were 2.1 and 4.5 μM, respectively.     

Analysis of Dichlorobenzene in Water by Solid‐Phase Microextraction

The solid‐phase microextraction (SPME) technique using a 100 μm film polydimethylsiloxane (PDMS) coated fiber has been examined with the aim to determine dichlorobenzene in aqueous samples. The feasibility of SPME‐GC‐ECD analysis has been evaluated. Absorption time of 30 min was selected and 1 min was long enough for complete desorption of the analytes in the injection port of the gas chromatograph. Linear ranges from 0.03 to 5 μg/L and method detection limits between 7 and 9 ng/L for dichlorobenzenes were obtained. The relative standard deviations were less than 12% for a spiking level of 3 μg/L. The proposed method was applied to determine dichlorobenzenes in spiked deionized water, ground water, and in industrial effluent samples.     

Studies on the Constituents from the Bark of Bauhinia Purpurea

In a previous paper, were ported a new stigmasteroyl glucoside derivative together with four known compounds. In addition to the above compounds, the isolation and identification of twenty‐four compounds from the same source are described here. Their structures were deter mined on the basis of spectral evidence as well as comparison with authentic samples. Those compounds included four waxes, four triterpenes, eight steroids, two glyceride, three flavonoids, and three phenylpropanoids. Some new compounds were found in mixtures of three alkyl ω‐hydroxyalkanoate, glyceride, and phenylpropanoids.     

Characterization of the superficial region of solids using the Rutherford backscattering method with charged particles

In the first part of this work, we show the basic principle of the Rutherford backscattering method and follow the possibilities and performance allowed. We also discuss how to choose the best experimental configuration to provide most significant spectrum in the case of glass surface analysis.     

Flavonol Glycosides and Cytotoxic Triterpenoids from Alphitonia Philippinensis

Three new flavonol glycosides, namely, isorhamnetin 3‐O‐(6″‐O‐(Z)‐p‐coumaroyl)‐β‐D ‐glucopyranoside ( 1 ), quercetin 3‐O‐α‐L ‐rhamnopyranosyl(1 → 2)‐α‐L ‐arabinopyranosyl(1 → 2)‐α‐L ‐rhamnopyranoside ( 2 ), and quercetin 3‐O‐α‐L ‐arabinopyranosyl(1 → 2)‐α‐L ‐rhamnopyranoside ( 3 ), were isolated from the stems of Alphitonia philippinensis. Their structures were established by spectral analysis. In addition, NMR data were assigned for ceanothenic acid ( 11 ). Some of the isolated triterpenoids and flavonoid glycosides showed cytotoxicity against human PC‐3 cells and hepatoma HA22T cells, and inhibition of replication on herpes simplex virus type‐1.     

Philinopsides A and B,Two New Sulfated Triterpene Glycosides from the Sea Cucumber Pentacta quadrangularis

Two new sulfated triterpene glycosides, philinopsides A ( 1 ) and B ( 2 ), were isolated from the sea cucumber Pentacta quadrangularis. Their structures were established by extensive spectral analysis (2D‐NMR and MS) and chemical evidence. Philinopside A ( 1 ) and B ( 2 ) showed significant cytotoxicity (ED₅₀ 0.75–3.50 μg/ml) against ten tumor cell lines. Compound 1 also significantly inhibited the proliferation, migration, and tube formation of human microvascular endothelial cells.