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A methanolic extract of the roots of Valeriana officinalis (valerian) was investigated for its lignan content. In addition to the lignans 8'-hydroxypinoresinol (1) and pinoresinol-4-O-beta-D-glucoside (2), which had already been isolated from valerian in an earlier study, the 7,9'-monoepoxylignans massoniresinol-4'-O-beta-D-glucoside (3), 4'-O-beta-D-glucosyl-9-O-(6' '-deoxysaccharosyl)olivil (4), and berchemol-4'-O-beta-D-glucoside (5) and the 7,9':7',9-diepoxylignans pinoresinol-4,4'-di-beta-O-D-glucoside (6), 8-hydroxypinoresinol-4'-O-beta-D-glucoside (7), and 8'-hydroxypinoresinol-4'-O-beta-D-glucoside (8) were identified. While lignans 3, 6, 7, and 8 had already been isolated from other plants, lignans 4 and 5 are new natural products. The lignans were investigated in radioligand binding assays at various receptors of the central nervous system, including GABA(A), benzodiazepine, 5-HT(1A), and adenosine A(1) and A(2A) receptors, to investigate their potential contribution to the pharmacological activity of valerian. The novel olivil derivative 4 proved to be a partial agonist at rat and human A(1) adenosine receptors exhibiting A(1) affinity and activity in low micromolar to submicromolar concentrations. Lignan 4 is the first nonnucleoside adenosine receptor agonist not structurally related to adenosine.

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Diffusion profiles and the solubility of Cu in Ge were measured in the temperature interval 850–1200 K by means of the spreading-resistance technique. From these data it is concluded that the diffusion of Cu in Ge involves the interchange between a highly mobile interstitial configuration, Cui, and a practically immobile substitutional configuration, Cus, with the aid of vacancies, V, via the so-called dissociative mechanism, Cui+V⇄Cus. The excellent agreement of the values of the vacancy contribution to the tracer self-diffusion coefficient in Ge, as calculated from our diffusivity and solubility data on Cu in Ge, with directly measured values of the 71Ge tracer self-diffusion coefficient from the literature demonstrates that self-diffusion in Ge occurs via vacancies. A comparison with the mechanisms of Au and self-diffusion in Si is presented.

From Valeriana alliariifolia we could isolate six new valepotnathydrines by CC and preparative HPLC. One hydrineand a corresponding valepotriate are esterified with an unsaturated acid (3-methyicrotonic acid). Analysis, isolation and structure eludication are reported.