Speciation of iron and manganese in dam water particles using electron spectroscopy for chemical analysis (ESCA)

The speciation of iron and manganese compounds retained by membrane filtration of dam water samples was studied by use of electron spectroscopy for chemical analysis (ESCA). Samples were taken at various depths and times of year from North Pine Dam near Brisbane, Australia. Both surface and bulk properties of samples representative of the water column profile were investigated. ESCA results showed that iron(III) compounds were found to predominate in the whole water column in any season of the year while the significance of iron(II) species varied in the hypolimnion (the bottom layer). In summer, although various ratios of manganese(II), manganese(III) and manganese(IV) compounds were found to occur down the water column, manganese(IV) compounds were predominant in the epilimnion (the top layer), while both manganese(II) and (IV) compounds predominated in the metalimnion (the middle layer) and the hypolimnion. The majority of Mn(IV) compounds were found throughout the water column after heavy rain and winter season. The ratios of atomic concentrations of iron and manganese as determined by atomic absorption spectrophotometry and ESCA are also discussed.     

Structures and Bioactivities of Steroidal Saponins Isolated from the Genera Dracaena and Sansevieria

The species Dracaena and Sansevieria, that are well-known for different uses in traditional medicines and as indoor ornamental plants with air purifying property, are rich sources of bioactive secondary metabolites. In fact, a wide variety of phytochemical constituents have been isolated so far from about seventeen species. This paper has reviewed the literature of about 180 steroidal saponins, isolated from Dracaena and Sansevieria species, as a basis for further studies. Saponins are among the most characteristic metabolites isolated from the two genera. They show a great variety in structural motifs and a wide range of biological activities, including anti-inflammatory, anti-microbial, anti-proliferative effects and, in most case, remarkable cytotoxic properties.     

Alternative chromatographic processes for no-carrier added 177Lu radioisotope separation

HPLC technique combined with the simple conventional column solid phase extraction (SPE) chromatography using di-(2-ethylhexyl)orthophosphoric acid (HDEHP) impregnated OASIS-HLB sorbent based SPE resins (OASIS-HDEHP) was developed for the separation of no-carrier added (n.c.a) ¹⁷⁷Lu from the bulk quantity of ytterbium target. This combination strategy was based on combining the advantages of the better resolution of HPLC separation of n.c.a ¹⁷⁷Lu from the few milligram level Yb target with the high capacity of the OASISHDEHP column for the separation of ¹⁷⁷Lu from the bulk Yb target. The production batches of several hundred mCi activity of n.c.a ¹⁷⁷Lu radioisotope separated from 50 mg Yb target activated in a nuclear reactor of medium neutron flux (Φ=5·10¹³ n·cm^?2·s^?1) were successfully performed using this combined separation technique. With the target irradiation in a reactor of higher thermal neutron flux or with the parallel run of several separation units, several Ci-s of n.c.a ¹⁷⁷Lu can be profitably produced on a commercial production basis.     

Hybrid Plasma – Prospects for Application in Medicine and Biology

Russian Physics Journal - Different schemes and designs of generators of low-temperature hybrid plasma produced by simultaneous ionization of plasma-generating medium by an electron beam with...     

Phytochemistry and Biological Activities of Iris Species Growing in Iraqi Kurdistan and Phenolic Constituents of the Traditional Plant Iris postii

A dozen Iris species (Iridaceae) are considered traditional remedies in Kurdistan, especially for treating inflammations. Phytochemical studies are still scarce. The information reported in the literature about Iris species growing in Kurdistan has been summarized in the first part of this paper, although, except for Iris persica, investigations have been performed on vegetal samples collected in countries different from Kurdistan. In the second part of the work, we have investigated, for the first time, the contents of the methanolic extracts of Iris postii aerial parts and rhizomes that were collected in Kurdistan. Both extracts exhibited a significant dose-dependent free radical scavenging and total antioxidant activities, comparable to those of ascorbic acid. Medium-pressure liquid chromatographic separations of the two extracts afforded l-tryptophan, androsin, isovitexin, swertisin, and 2″-O-α-l-rhamnopyranosyl swertisin from the aerial parts, whereas ε-viniferin, trans-resveratrol 3,4′-O-di-β-d-glucopyranoside, and isotectorigenin were isolated from the rhizomes. This is the first finding of the last three metabolites from an Iris species. The various remarkable biological activities of isolated compounds scientifically sustain the traditional use of I. postii as a medicinal plant.     

New cassane-type diterpenes of Caesalpinia crista from Myanmar

Seven new cassane-type diterpenes, caesalpinin MF-ML (1-7), and a new norcassane-type diterpene, norcaesalpinin MD (8), have been isolated from the CH2Cl2 extract of seed kernels of Caesalpinia crista from Myanmar, together with sixteen known cassane-type diterpenes, 7-acetoxybonducellpin C, caesaldekarin e, caesalmin C, caesalmin G, 2-acetoxycaesaldekarin e, zeta-caesalpin, caesalpinin D, caesalpinin E, caesalpinin F, caesalpinin H, caesalpinin I, caesalpinin J, caesalpinin K, caesalpinin M, caesalpinin N, and caesalpinin O. The structures of the isolated compounds were elucidated by the use of spectroscopic techniques.     

Methyl migrated cassane-type furanoditerpenes of Caesalpinia crista from Myanmar

From the CH2Cl2 extract of seed kernels of Caesalpinia crista from Myanmar, two rare and biogenetically interesting methyl migrated cassane-type furanoditerpenes [caesalpinins MM (1) and MN (2)] and two normal cassane-type furanoditerpenes [caesalpinins MO (3) and MP (4)] have been isolated, together with eight known cassane-type diterpenes, 1-deacetoxy-1-oxocaesalmin C (5), 1-deacetylcaesalmin C (6), caesalmin C (7), bonducellpin C (8), caesaldekarin e (9), 2-acetoxycaesaldekarin e (10), 2-acetoxy-3-deacetoxycaesaldekarin e (11), and norcaesalpinin E (12). Among the known compounds, compounds 5 and 6 were for the first time isolated from a natural source. The structures of these compounds were elucidated by the use of spectroscopic techniques.     

Synthesis of 2′-amino-17-cyclopropylmethyl-6,7-dehydro-3,14-dihydroxy-4,5α-epoxy-6,7:4′,5′-thiazolomorphinan from naltrexone

Fusion of an azole moiety at C-6 and C-7 of naltrexone ( 1 ) is illustrated by the synthesis of the title compound 8 . Bromination of 3-O-methylnaltrexone led to the 1,7α-dibromo derivative which reacted with thiourea to attach the 2-aminothiazole ring to C-6 and C-7 of naltrexone. After converting the amino and alcohol groups to trimethylsilyl derivatives, the aromatic bromo group was removed by halo-lithium interchange with butyllithium, followed by hydrolysis with water. In the final step of the synthesis, the methyl ether was cleaved by boron tribromide to generate 8 . An alternate synthesis of 8 commenced with 3-O-acetylnaltrexone ( 9 ). Bromination of 9 in acetic acid in the presence of hydrobromic acid produced a mixture of 3-O-acetyl-7α-bromonaltrexone ( 10 ) and 7α-bromonaltrexone ( 11 ), both, as hydrobromides. Reaction of this mixture with thiourea furnished 8 (62% from 1 ). While ¹H and ¹³C chemical shifts of all compounds are reported, those of 11 hydrobromide and 8 dihydrochloride were established unequivocally.     

Synthesis of aryl ω-(1-methyl-5-imidazolyl and 1H-5-tetrazolyl)alkyl ketones

Successful syntheses of 2,4-dichlorophenyl 2-(1-methyl-5-imidazolyl)ethyl and 2,4-dichlorophenyl 3-(1-methyl-5-imidazolyl)propyl ketones are described. In addition, syntheses of 2,4-dichlorophenyl and 4-chlorophenyl 3-(1-methyl-1H-5-tetrazolyl)propyl ketones are reported.