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A pentachloro derivative, the structure of which was proved by x-ray structure analysis, in addition to a new dichlorocarbene derivative were obtained for the first time by dichlorocyclopropanation of arglabin guaianolide. The stereochemistry of the principal reaction product was established.

A chromatographically inseparable crystalline mixture of the previously undescribed quercetin-4′-O-β-galactopyranoside and the known quercetin-3-O-β-glucopyranoside (isoquercitrin) in a 7:5 ratio was isolated from the extract of the aerial part of Filipendula ulmaria (L.) Maxim.

The structure of the sesquiterpene ketone buddledin C isolated from Pulicaria prostrata (Gilib.) Aschers., was confirmed by XSA. The stereochemistry of its epoxide, which was formed selectively by treating it with hydrogen peroxide in alkaline solution, was proposed based on quantum-chemical and molecular-mechanical calculations.

2-Chloro-4,5α-epoxy-α-santonin and 2-chloro-α-santonin, the molecular structure of which was confirmed by an XSA, were produced by reacting α-santonin and chlorine in aqueous acetonitrile. It was found that 2-chloro-α-santonin is highly effective against trichomonas.

Four sesquiterpene lactones with the germacrane structure were isolated from the aerial part of Stizolophus balsamita. X-ray structure analyses showed that two of them were previously known balsamin derivatives. A third was a crystalline isomorphous mixture of the known lactone stizolin and 11,13-dihydrostizolin in a 53:47 ratio. The biological activities of the balsamin derivatives were investigated.

Reaction of the germacranolide stizolicin with secondary amines formed normal products of a Michael reaction at the exomethylene group and simultaneously led to solvolysis with cleavage of the acyl group. The structures of the molecules were established by XSA. Use of the HI salt of one of the resulting amines enabled the proof of its absolute configuration and that of the starting stizolicin, which had previously only been proposed. Stizolicin and the synthesized compounds were screened for antimicrobial and antitrichomonal activity.

Dibromocarbene and bisdichlorocarbene derivatives of the available sesquiterpene lactone arglabin were synthesized for the first time. The structures of the molecules were established by spectra methods and XSA.

Chemical components from the aerial part of the Kazakhstan population of Artemisia pontica, from which the rarely encountered flavonoids 7-O-methyl- and 4′,7-di-O-methyl-esters of apigenin were isolated for the first time, were identified. The complete chemical composition of the essential oil was established using GC-MS.

1,10-Dihydro-1α,10α-dinitrogrossmisin was synthesized by bubbling gaseous nitrosyl chloride through a chloroform solution of the guaianolide grossmisin. The molecular structure was determined by X-ray. It was found that the formation of similar dinitrates is accelerated by using NOCl containing nitrogen dioxide.

Bubbling gaseous nitrosylchloride through a chloroform solution of the guaianolide achillin produces very slowly but selectively 1,10-dihydro-1α,10α-dinitroachillin. This product rapidly, quantitatively, and irreversibly isomerizes into the dinitrocarboxylic acid with retention of the guaian carbon skeleton upon dissolution in pyridine. The structures of the new compounds were found by x-ray structural analysis

The oxime of artemisia ketone is smoothly converted to the pyrazole derivative by sodium nitrite and acetic acid in CHCl3. The structure of the pyrazole was found by x-ray structural analysis. The PMR and13C NMR spectra were interpreted using two-dimensional1H−13C NMR (COSY, COLOC).

Four phenolic components are isolated from the CHCl 3 extract ofEmpetrum nigrumL. Three of them are known from this plant. The fourth (6,8-dimethylpinocembrine) is isolated from crowberry for the first time. The previously proposed structure for 2'-methoxy-4'-hydroxy- α,β-dihydrochalcone is confirmed by x-ray structure analysis

The new sesquiterpene lactone ajanolide A has been subjected to hydrolysis and epoxidation. The structures of the derivatives obtained have been established by x-ray structural analysis.

Adducts of dihalocarbenes generated from chloroform and bromoform were prepared by reaction with estafiatin guaianolide. Their structures were established by XSA.

A novel eudesmane sesquiterpene lactone, the structure of which was established by XSA, was isolated from Artemisia tournefortiana.

The sesquiterpene lactone pulchellin C has been epoxidized with trifluoroperacetic acid. The spatial structures 4(15)-α-epoxypulchellin and 5α, 6α-epoxyalantolactone have been established by x-ray structural analysis.

A new sesquiterpene lactone having the structure 3β-acetoxy-1β-hydroxy-6β, 7α(H)-germacra-4,10(14), 11(13)-trien-6, 12-olide has been isolated fromArtemisia subchrysolepis Filat. and has been called subchrysin. Its stereochemistry has been established by x-ray structural analysis.

The sesquiterpene lactone argolide has been converted into its 1(10)-epoxide. The structure of the latter has been investigated by NMR, x-ray structural analysis, and molecular mechanics.

A tetrabromo derivative of arglabin was synthesized stereoselectively. The molecular structure of the new compound was established using PMR and 13C NMR spectra and an x-ray structure analysis. Its antifungal activity was demonstrated.

A new bisazulene, the structure of which was established using x-ray structure analysis and PMR and 13C NMR spectra, was isolated from essential oil of Ajania fruticulosa obtained by steam distillation.

The germacranolide 11,13-dihydroridentin, for which the previously unknown S-configuration of the asymmetric center on C-11 was established, was isolated for the first time from Artemisia pontica L.

Dehydroisoleucomisin (anhydroaustricin) was converted in good yield to guai-1(10),3,5,7(11), 8-pentaen-2-on-12,8-olide by the action of anhydrous HCl in dry DMF. The chemical structure of the product was established using spectral data. The probable formation scheme of this lactone was proposed to include a series of prototopic transformations and ionic dehydrogenation of intermediates.

(3aR*,6aR*)-3,3,5,5-Tetramethyl-3a,6a-dinitro-3a,6a-dihydro-3H-cyclopentano[c]pyrazol-2-oxide was formed by reaction of cycloartemisiaketone oxime [4,4-dimethyl-2-(1-methylethylidene)cyclopentanone oxime] with AcOH and NaNO2 in CHCl3 solution. The structure was solved by x-ray structure analysis.

The presence of bioregulators of animal organisms — dolichols — has been established in the needles, needle-free shoots, and bark of the Siberian stone pine. The qualitative and quantitative compositions of the mixtures of the isoprenologues and polyprenols have been established by the HPLC method. In addition, known diterpene alcohols ((E,E,E)-geranylgeraniol and labd-8(17),13E-dien-15-ol) esterified with higher fatty acids have been identified in the bark.

A mixture of gibberellin A3 derivatives with 1(10)-ene-2β,3β-diol and 1(10)-ene-2α,3β-diol (2:5) groups, readily obtained from gibberellin A3, has been used for a new and simple synthesis of gibberellin A8 and its esters. The hydrolysis of GA3 and the iodolactonization of a mixture of the 2-epimers was carried out in aqueous solution in a single flask, as also was a synthesis of GA56 from GA3 by a method that we have modified. The mixture of 1β-iodides of GA8 and GA56 was separated by chromatography on SiO2 in the form of methyl or p-bromophenacyl esters which were then deiodinated and the methyl or p-bromphenacyl ester of GA8 was isolated. Free GA8 was obtained by the dephenylation of the latter ester. By two-dimensional NMR spectroscopy we succeeded in assigning all the signals in the13C and1H NMR spectra of the methyl esters of GA8 and GA56. In an attempt to obtain GA5 methyl ester by the action of trimethylchlorosilane/sodium iodide on the 2α,3β-diol system in GA56 methyl ester, the 8,13-epimer of the latter was formed, the structure of its molecule being established from the results of X-ray structural analysis.

It has been established that during the cyclization of 5β-acetoxyisocembrol under the action of HCOOH + D2O the D atom enters position 7α of the product molecules exclusively, which is in harmony with the proposed cyclization scheme. Using model compounds, an alternative scheme for the formation of one of the products has been disproved.

The structures and the stereochemistries of all the main products of the carbocyclization of 5β-acetoxyisocembrol on its interaction with aqueous formic acid in chloroform have been established. This reaction takes place more selectively than the cyclization of cembrene under the same conditions and is distinguished by the complete predominance in its last stage of the 1,5-hydride shift from C-15 to C-4 over the splitting out of a proton from the C(4)-methyl group.

Under the action of N-bromosuccinimide in aqueous acetone, cembrene has given a low yield of a cyclization product, the structure and stereochemistry of the molecule of which have been established by x-ray structural analysis. In contrast to the cyclization of cembrene under the action of formic acid, in the reaction under consideration a 1,5-hydride shift in the last stage dominates substantially over the splitting out of a proton from the methyl group at C-4.

1α,2α-Epoxygibberellin A3 has been obtained for the first time in almost quantitative yield by the dehydroiodination of the known 1β-iodogibberellin A56, and the structure of its molecule has been established by the XSA method. An interpretation of all the signals in its1H and13C spectra has been made from the results of two-dimensional NMR. In the amylase biotest, 1α,2α-epoxgibberellin A3 exhibited an activity amounting to one third of the activity of gibberellin A3 at concentrations of 10−7 to 10−9 M.

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.

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.

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

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.

Centaurea scabiosa (Asteraceae) has a wide range in the northern hemisphere and is common in Siberia, Europe, and Scandinavia [1]. This plant has long been interesting for its polyacetylene derivatives [2-4], after which Czech researchers discovered in it the germacranolide scabiolide [5, 6], which is structurally similar to cnicin [7]. We investigated the chemical composition of the air-dried aerial part of C. scabiosa from Tomsk District using extraction by diethylether and did not isolate scabiolide as reported earlier [6]. Isolation of Lactone 1. Raw material (0.5 kg) was soaked in CHCl3 (3 × 2 L) at room temperature. Filtration and removal of solvent produced a syrupy extract in 2% yield. The resulting product (10 g) was chromatographed over SiO2 with elution by CHCl3 and then CHCl3:(CH3)2CO mixtures with an increasing gradient of the latter. Removal of solvent from the CHCl3:(CH3)2CO (9:1) eluent produced a precipitate that had mp 200-201°C and Rf 0.13 (CHCl3) after washing with Et2O. Lactone 1 was a white with a cream tint finely crystalline powder, mp 200-201°C, lit. mp [10] 205°C. The IR spectrum had the following absorption bands (ν, cm-1): 3475 (OH), 1740 (C=O of a 5-membered ring conjugated to an unsaturated bond), 1650 (C=O), 1450 and 1410 (=CH2). Chromatography of the CHCl3 extract isolated grosshemin (1), which has been known since 1964 [8]. Its correct structure was established by Breton et al. [9]; the stereochemistry, by Samek et al. [10]. The latest publication did not completely assign the signals for H-1 and H-4 in the PMR spectrum and did not describe the signals for H-2 and H-5 (in DMSO-d6 solution).

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 (3832) 34 452, e-mail: raldugin@nioch.nsc.ru; 3) AO NPTs Fitokhimiya, 100009, Karaganda, Gazalieva, 4,Republic of Kazakstan, fax 8-(3212) 43 37 73, e-mail: arglabin@phyto.kz. Translated from Khimiya Prirodnykh Soedinenii, No. 3, p. 317, May-June, 2008. Original article submitted January 31, 2008.

This review describes cyclocembrane compounds isolated from plants, marine organisms, and insects. A systematization of cyclized diterpenoids according to the types of carbon skeletons is given.

It has been established that in the photooxidation of isocembrol, in addition to other compounds, five products of oxidation at the C11 double bond are formed, and their structures and stereochemistry have been established by chemical transformations and physicochemical methods. In the stereochemical respect, the photooxidation of isocembrol at the C11 double bond is similar to its epoxidation at the same bond.

The correct structure has been established for the compound obtained on the treatment of the methyl ester of gibberellin A3 with zinc in boiling acetic anhydride, to which the erroneous structure (II) was previously assigned. A mechanism of the formation of compound (II) is suggested which includes an intramolecular diene condensation between an acetate carbonyl group and the conjugated diene system in the intermediate mixed anhydride (V).