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An efficient one-pot procedure has been proposed for the synthesis of 8-methyl-5-[(methylsulfanyl) methyl]-3-thiabicyclo[3.3.1]non-7-en-6-one from accessible natural raw materials. A stable complex of the title compound with gold(III) has been obtained by the extraction method, and the mode of its coordination to the metal ion has been determined by IR and NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Quantitative determination revealed the presence of storage glucan (6.0%), fucoidan (19.2%) and alginate (12.7%) in the biomass of the brown alga Punctaria plantaginea collected from the Sea of Japan. The polysaccharides were isolated from the alga by fractional extraction followed by additional purification procedures. Unlike the well-known laminarans the storage polysaccharide from P. plantaginea was shown to be a linear (1→6)-β- d-glucopyranan, which is new for brown alga. The content of guluronic acid (G) residues in the alginate molecules exceeded the content of mannuronic acid residues (M), M/G = 0.5. Poly-G and poly-MG blocks were isolated from the products of partial hydrolysis of alginic acid; however, a heterogeneous mixture of polysaccharide fragments was obtained instead of the expected poly-M fraction. Preliminary data suggests that fucoidan from this alga is a new for brown algae type of sulfated polysaccharide (xylofucan) with a main backbone built of α- l-fucopyranose residues. This chain contains multiple sulfate groups and single non-sulfated β- d-xylopyranose residues as substituents. [ABSTRACT FROM AUTHOR]

Spent fuel discharged from Fast Breeder Test Reactor (FBTR) in Kalpakkam is being reprocessed by modified plutonium uranium reduction extraction (PUREX) process using 30% TBP (tributylphosphate) as extractant in the presence of heavy normal paraffin (HNP) as diluent. Partitioning of uranium (U) and plutonium (Pu) is carried out using oxalate precipitation method. Uranium oxide product obtained by this method contains appreciable amount of plutonium which has to be recovered. Recovery of plutonium from this uranium oxide product is carried out by reducing Pu to inextractable Pu(III) using hydroxyurea (HU) and then uranium is extracted into 30% TBP. A small amount of Pu which is extracted in the organic phase is stripped back to aqueous phase by scrubbing with scrubbing agent containing 0.1 M HU in 4 M nitric acid. Similarly U and Pu are co-extracted into 30% TBP and then Pu is removed by scrubbing with 0.1 M HU in 4 M nitric acid. Further decontamination from Pu is obtained in the stripping stages. By this method Pu contamination in the uranium oxide is brought from 7300 ppm to 0.4-3 ppm (wt/wt). This uranium product obtained can be handled on table top. [ABSTRACT FROM AUTHOR]

The purification of lipoxygenase in soybeans (richest known source) was attempted by precipitation, using polyethylene glycol, followed by aqueous two-phase extraction (ATPE). The preliminary purification by precipitation was standardized which resulted in two-fold purification. The influence of process parameters such as phase forming salt, molecular weight of phase forming polymer, tie line length, and phase volume ratio on the partitioning behavior of lipoxygenase during ATPE was investigated. The aqueous two-phase system of polyethylene glycol 6000 and ammonium sulfate, with inherent pH of 5.2, was found to be most suitable. The tie line length of 41.25% and volume ratio of 1.7 have resulted in 125% activity recovery with the overall purification factor of 4.38 compared to crude enzyme extract. [ABSTRACT FROM AUTHOR]

Physicochemical substantiation and improved more effective technologies for C-hydrocarbons separation and 1,3-butadiene purification with the help of polar extragents are given, such as compressorless extractive rectification with the use of an intermediate desorbent, extractive rectification of the butane- n-butene fraction with preliminary isomerization of 1-butene into 2-butenes, the combined removal of -acetylenes C and methylallene by rectification with a small introduction of the extragent, and the hydration of butenyne in the C fraction and distillation of propyne from it. [ABSTRACT FROM AUTHOR]

Results of the application of microfine ionites of different classes for sorption methods in the production of versatile drugs are systemized. Kinetic and dynamic parameters of sorption isolation and chemical purification of drugs with participation of ion-exchanger of small graining are discussed; essential advantages of their application allowing intensification of ion-exchange technological processes of drugs production are determined. The review can be useful at elaboration of new sorption methods used for the production of the wide assortment of drugs and, first of all, antibiotics, enzymes, and vitamins. [ABSTRACT FROM AUTHOR]