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Bu 3 Sn-endded poly(vinyl)s with biological activity were obtained by the radical polymerization of vinyl monomersusing thianthrene cation radical/ n Bu 3 H. Thianthrene cation and stannyl radicals promoted the homopolymerization andcopolymerization of styrene and ethyl vinyl ether having number average molecular weights of 2000-3100. Tributyltinhydride functions as a chain transfer agent. Such polymereization by cationic thianthrene and stannyl radicals could providesome clues for the biological reaction in living animals. Plausible polymerization mechanisms were suggested.Key words: Thianthrene, Cation Radical, Tribuyltin Hydride, Polymerization 1. Introduction Radical chemistry has received great attention due toits main role in various important organic reactions [1] .Nevertheless, little is known for the reactions withunsaturated alkenes and alkynes although cationic rad-icals are known to react with various nucleophiles [1] .The addition of cationic radicals such as R 2 NH

Tributyltin hydride (), an endocrine disruptor, was slowly polymerized by the group 4 -selectride (Cp`

Trialkyltin n-Bu 3 SnH, an endocrine disruptor, was slowly converted by the catalytic action of group 4 Cp 2 MCl 2 /Red-Al (M = Ti, Zr, Hf) to produce two phases of products: one is an insoluble cross-linked solid, polystannane in 7-23%yield as minor product via redistribution/dehydrocoupling combination process, and the other is an oil, hexabutyldistannanein 69-90% yield as major product via simple dehydrocoupling process. Redistribution/dehydrocoupling process firstproduced a low-molecular-weight oligostannane possessing partial backbone Sn-H bonds which then underwent anextensive cross-linking reaction of backbone Sn-H bonds, leading to an insoluble polystannane. This is the first excitingexample of redistribution/dehydrocoupling of a tertiary hydrostannane catalyzed by early transition metallocenes.Key words : Redistribution, Dehydrocoupling, Polystannane, Metallocene, Catalyst, Endocrine 1. Introduction Inorganic polymers as substitutes for organic poly-mers are very important for diverse industrial applica-tions

Polymerization of vinyl monomers is promoted by thianthrene cation radical as a part of our research concerning the reactions of various agents with readily isolable, yet highly reactive species and elucidate the biological activity. Thianthrene cation radical initiated the homopolymerization and copolymerization of styrene and ethyl vinyl ether. The polymerization yields decreased as the concentration of phenylacetylene or diphenylethylene increased. Such polymereization by cationic thianthrene radical could provide some clues for the reaction in living animals. Comments on possible polymerization mechanisms were suggested.

The strain KCTC 11629BP, isolated from spontaneously fermented pine needle extract (FPE), showed fibrinolysis activity. The isolated strain was analyzed in physiological and biochemical experiments. Based on 16S rDNA sequencing and phylogenic tree analysis, the strain was identified to be a part of the genus Acetobacter, with Acetobacter senegalensis and Acetobacter tropicalis as the closest phylogenetic neighbors. Based on genotypic and phenotypic results, it was proposed that bacterial strain KCTC 11629BP represents a species of the genus Acetobacter. The strain was thusly named Acetobacter sp. FP1. In conclusion, Acetobacter sp. FP1 isolated from FPE possesses fibrinolytic activity.