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Vilsmeier—Haack formylation of methyl lambertianate results in its 16-formyl derivative as the predominant product, which readily enters the intramolecular reaction of photochemical [2+2]-cycloaddition in the absence of a sensitizer.

Acetonation of rhaposerin is accompanied by migration of the O-acetyl group. Acetonation of 15-O-deacetylrhaposerin afforded isomeric O-isopropylidene derivatives containing five- and six-membered rings.

The reaction of grossmisin (8α-hydroxyachillin,1) with chlorine in benzene afforded a mixture of products. The less polar product readily crystallized after chromatography. According to the X-ray diffraction data, this product has the structure of 1α,10β-dichloro-1,10-dihydrogrossmisin. The second chloro derivative of grossmisin,viz., 8β-chloroachillin, was prepared in good yield by the reaction of lactone1 with PCl5 in CHCl3 in the presence of Py.

Using dimeric NMR spectroscopy, a complete interpretation of the1H and13C NMR spectra of the diterpene hydrocarbon cembrene has been made. The experimental values of the SSCs for the1H atoms in the PMR spectra of cembrene agree well with those calculated for the lowest-energy (“crystal”) conformation. In the light of the observation of intramolecular NOEs and of the low-temperature13C NMR spectra, it has been concluded that the cembrene molecule retains the “crystal” conformation in solution.

Using the scheme for the group separation of the oleoresins of conifers, the quantitative and qualitative composition of the oleoresin of the Schrenk pinePicea shrenkiana Fish. et May has been investigated. Thirty-eight diterpenoids have been identified, one of which (palustradiene) has been detected in conifers for the first time.

A review is given for the first time of the results of investigations of Soviet and foreign authors on the isolation of triterpenoids from the bark, needles, oleoresin, and seeds of various species ofAbies (fir) and the determination of their structures and properties. Features of the PMR, mass, UV, and CD spectra of the compounds under consideration are discussed specially and information is given on their classification, distribution in firs, and biological activities.

Polyisoprenoid alcohols (polyprenols and dolichols) from leaves and branches of European alder (Alnus glutinosa (L.) Gartn.) were studied by1H NMR spectroscopy and HPLC. Data on dynamics of relative monthly (May–August) content of each isoprenolog of polyprenols and dolichols were obtained.

Two new 3,4-secotriterpene acids have been isolated in the form of dimethyl esters from the acid fraction of the oleoresin of the silver firAbies alba Mill. On the basis of spectral characteristics and the results of a chemical correlation with the known triterpenoids methyl abiesolidate, dimethyl abiesonate and methyl firmanoate it has been established that they are (25R)-3,4-seco-9β-lanosta-4(28),7-dien-23-one-3,26-dioic acid and (25R)-3,4-seco-abiesa-4(28),7,14(30)-trien-23-one-3,26-dioic acid.

From the epigeal part ofArtemisia altaiensis Krash. we have isolated 3-oxocostus acid (selina-4,11(13)-dien-3-on-12-oic acid), the structure of the molecule of which has been confirmed by x-ray structural analysis, while its absolute configuration has been established from the results of circular dichroism.

A new triterpenoid lactone with a reported rearranged lanostane skeleton was isolated from the neutral fraction of the extract from the needles of Siberian fir. Its structure was established on the basis of chemical transformations and NMR spectra using two-dimensional (COSY, COLOC) NMR spectroscopy.

Vilsmeier—Haack formylation of methyl lambertianate results in its 16-formyl derivative as the predominant product, which readily enters the intramolecular reaction of photochemical [2+2]-cycloaddition in the absence of a sensitizer.

The dependence of the C C–C O group chirality on the conformation of the α-methylene-γ-lactone ring in sesquiterpene lactones has been established; the known cases in which Geissman's rule is violated are explained by inversion of this ring.

Oxidation of (+)-sabinol, (1S,3R,5S)-1-isopropyl-4-methylidenebicyclo[3.1.0]hexan-3-ol, by active MnO2 afforded not the expected sabinone but only its [4+2]-cyclodimer. The molecular structure of the latter was established by X-ray diffraction analysis. The 1H and 13C NMR spectra of this cyclodimer were interpreted using 2D NMR spectroscopy.

The reactions of the natural flavonoids tectochrysin and pinostrobin with chlorine in methanol afforded for the first time their 6,8-dichloro derivatives. Under the reaction conditions, dichloropinostrobin was transformed further into a tetrachloromethoxy derivative. The molecular structure of the latter was established by X-ray diffraction analysis.

The stereoselective synthesis of two phosphorus-containing derivatives of the known guaianolide arglabin was carried out for the first time. The molecular structures of these products were established based on the spectroscopic data and the results of X-ray diffraction analysis of one of these compounds.

The 3-O-palmitate and 3-O-tridecanoate of gibberellin A3 have been synthesized and monomolecular Langmuir-Blodgett films have been obtained from them.

Preventive effect in influenza can be attained by intramuscular injections of fir (Abies) polyprenols. One of 5 tested polyprenol preparations (No. 1), injected 2 days before aerogenic infection with influenza virus, reliably protected mice from disease. Mice pretreated with polyprenol preparations or Hanks' solution did not differ by accumulation of interferon in the lungs One day after aerogenic infection. Three days after injection of polyprenol preparation No. 1 the weights of the spleen and thymus significantly decreased. One day after injection cell count in the bronchoalveolar tract of mice was almost 2-fold higher than in the control at the expense of lymphocytes and macrophages. After 3 days the relative and absolute counts of macrophages decreased and those of lymphocytes decreased significantly. Three days after injection macrophages were 2-fold more active in absorption of zymosan granules. Preparation No. 1 affected the production of superoxide anion radicals, whose production by all macrophages in the bronchoalveolar tract of mice was significantly higher on day 1 postinjection than on day 3 and higher than on days 1 and 3 after injection of preparation No. 2.

The reaction of grossmisin (8α-hydroxyachillin,1) with chlorine in benzene afforded a mixture of products. The less polar product readily crystallized after chromatography. According to the X-ray diffraction data, this product has the structure of 1α,10β-dichloro-1,10-dihydrogrossmisin. The second chloro derivative of grossmisin,viz., 8β-chloroachillin, was prepared in good yield by the reaction of lactone1 with PCl5 in CHCl3 in the presence of Py.

The reaction of sesquiterpene lactone achillin with chlorine in methanol afforded four products,viz., two monochlorides and two dichlorides. One of these monochlorides is an intermediate in the formation of both dichlorides. The structures of the reaction products were established by two-dimensional NMR spectroscopy. The structure of one of the products was also established by X-ray diffraction analysis.

A new quercetin glycoside named filimarin was isolated from honeysweet (Filipendula ulmaria L. Maxim.) by colun chromatography over polyamide and silica gel. Based on chemical and spectral data, the structure of filimarin is identified as quercetin-4′-O-β-D-galactopyranoside. Results of voltammetric measurements showed that filimarin possesses pronounced antioxidant activity that is comparable with that of dihydroquercetin and ascorbic acid.

The structure of new trinortriterpene netural compounds formed as the result of the fragmentation of the side chains during the saponification of methyl esters of α,β-unsaturated γ-keto acids under the action of alcoholic alkali have been established by physicochemical methods.

syerlan75@yandex.ru; 2) N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Division, Russian Academy of Sciences, 630090, Novosibirsk, prosp. Akad. Lavrent′eva, 9, Russia, fax +7-(3832) 3 44 52, e-mail: raldugin@nioch.nsc.ru; 3) AO NPTs Fitokhimiya, 100009, Karaganda, Gazalieva, 4, Republic of Kazakhstan, fax +7-(7212) 43 37 73, e-mail: arglabin@phyto.kz. Translated from Khimiya Prirodnykh Soedinenii, No. 4, p. 436, July-August, 2008. Original article submitted January 31, 2008.

With the use of a number of known and two specially synthesized cembranoids it was established that the growth-inhibiting activity of membrane alcohols does not change appreciably on the inversion of the configuration of the Δ2 double bond in their molecule.

Fitokhimiya, 100009, Karaganda, Gazalieva, 4, fax 8(3212) 43 37 73, e-mail: arglabin@phyto.kz; 3) N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Division, Russian Academy of Sciences, 630090, Novosibirsk, prosp. Akad. Lavrent′eva, 9, fax (3832) 34 47 52, e-mail: raldugin@nioch.nsc.ru. Translated from Khimiya Prirodnykh Soedinenii, No. 2, p. 192, March-April, 2007. Original article submitted October 9, 2006.