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In extension of our research in the field of biomimetic transformations of germacranic sesquiterpene γ-lactones [1, 2] we performed by the action of formic acid a stereocontrolled transannular carbocyclization of Е,Е-germanocranolide hanphillin (I) isolated from Noble Yarrow (Achillea nobilis L.), and obtained new trans-fused 5α(Н),10β(СH 3 )eudesmanolides II and III in the yields of 65 and 30% respectively.As shown in the scheme the acid-catalyzed 5,10carbocyclization of compound I proceeds evidently through a regioselective protonation of the most electron-donor and spatially available Δ 1,10 -double bond of compound I followed by a stereospecific nucleophilic attack by the Δ 4,5 -double bond leading via a tertiary carbocation to the trans-fused eudesmanolides II and III (Scheme 1).The stereocontrolled 5,10-carbocyclization of compound I occurs also in the presence of СН 3 СО 3 Н and С 6 Н 5 СО 3 Н in СH 2 Сl 2 at room temperature giving trans-eudesmanolides formerly isolated from plant sources [3, 4] epiartekalin (IV) and ridentin-В (V) in 45 and 53% yields (Scheme 2).Compounds II and III. To a solution of 0.3 g (1.2 mmol) of compound I in 15 mL of СНСl 3 was added dropwise at room temperature 4.6 mL of 99% НСО 2 Н. The reaction mixture was stirred at room temperature, then washed with 10% solution of NaHCO 3 (2 × 10 mL), with water (3 × 10 mL), dried with MgSO 4 , the solvent was distilled off in a vacuum. The residue (0.33 g) was chromatographed on a column packed with silica gel (eluent hexane-ethyl acetate, 2 : 3 and 1 : 4). -1 1 (1 3)-e n -6, 12 -ol i d e , o r (3aS,5aS,9R,9aS,9bS)-5a,9-dimethyl-3-methylideneoctahydronaphtho[1,2-b]furan-2,8(3H,4H)-dione (II). Yield 0.193 g (65%). R f 0.54 (hexane-ethyl acetate, 2 : 3). Colorless crystals, mp 136-138°С. -O xo e u d es m

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At present, non-benzenoid aromatic hydrocarbons are widely used as precursors for the synthesis of new materials with useful electronic properties. In particular, the non-alternative aromatic hydrocarbon azulen with a unique dipole structure and a tendency to form stabilized radical ions should be predetermined as a building block for obtaining new π-conjugated systems with interesting optoelectronic properties. This article discusses the directed synthesis and study of optical properties of new donor-acceptor compounds based on azulene. It was shown that for the synthesis of donor-acceptor phenylketone azulenes, the reaction of directed (to positions С1 and С3) acylation with benzoyl chloride in the presence of Li2MnCl4 in tetrahydrofuran was used for the first time as a key step. It was found that push-pull phenyldicyanovinyl azulenes obtained by Knoevenagel condensation of azulenylketones with malononitrile flow easily (with an increase in the yield of end products) in the presence of pyridine in dimethyl sulfoxide. Electron UV-visible spectra of phenyldicyanovinyl azulene compounds showed strong absorption bands in the visible region (λmax = 452 and 434 nm) caused by intense intramolecular charge transfer between the donor azulene ring and the acceptor phenyldicyanovinyl group.