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(17R)-17,18-Dipropargyloxylabda-13,15-diene was synthesized and underwent Cu-catalyzed cycloaddition with 1,10-diazodecane or 1,2-bis(2-azidoethoxy)ethane to produce macroheterocycles of the furanolabdanoid decalin fragment. The macroheterocyclic labdanoids showed significant cytotoxicity in MEL-8, MT-4, and U-937 human tumor cell models.

Twenty-one phenolic compounds (1–21) including dihydrocinnamic acid, isoflavonoids, flavonoids, coumestans, pterocarpans, chalcones, isoflavan and isoflaven, were isolated from the roots of Glycyrrhiza pallidiflora Maxim. Phloretinic acid (1), chrysin (6), 9-methoxycoumestan (8), isoglycyrol (9), 6″-O-acetylanonin (19) and 6″-O-acetylwistin (21) were isolated from G. pallidiflora for the first time. Isoflavonoid acetylglycosides 19, 21 might be artefacts that could be produced during the EtOAc fractionation process of whole extract. Compounds 2–4, 10, 11, 19 and 21 were evaluated for their cytotoxic activity with respect to model cancer cell lines (CEM-13, MT-4, U-937) using the conventional MTT assays. Isoflavonoid calycosin (4) showed the best potency against human T-cell leukaemia cells MT-4 (CTD50, 2.9 μM). Pterocarpans medicarpin (10) and homopterocarpin (11) exhibit anticancer activity in micromolar range with selectivity on the human monocyte cells U-937. The isoflavan (3R)-vestitol (16) was highly selective on the lymphoblastoid leukaemia cells CEM-13 and was more active than the drug doxorubicin

The corresponding hydrazones and thiosemicarbazones were synthesized via the reaction of pinostrobin hydrazone with carbonyl compounds (aromatic aldehydes, acetone) or alkyl(aryl)isothiocyanates, respectively. The new pinostrobin derivatives showed significant cytotoxicity (MTT-assay) against MT-4, CEM-13, and U-937 human tumor cell models.

New isopimaric acid derivatives containing amines and methyl esters of α-, β-, and ω-amino acids were prepared. Conditions were found for cyclic isomerisation of isopimaric acid propargylamide into 2-(dodecahydrophenanthren-1-yl)-5-methyloxazole or 2-(dodecahydrophenanthren-1-yl)-5-methylene-4,5-dihydrooxazole. The latter was selectively modified by adding the methyl ester of (2-methylamino)butanoic acid at the oxazole C-5 position.

19-(2,6-Dimethylpyrid-4-yl)-20,29,30-trinorlupanes in addition to triterpenoid derivatives condensed in ring A of the pyran-4-one ring were synthesized for the first time from betulin, betulin diacetate, and methyl esters of 3-acetylbetulinic and betulonic acids.

Methods were proposed for preparing 15,16-dihydroisopimaric acid and its methyl ester. Oxidation of methyl dihydroisopimarate through the action of 3-chloroperbenzoic acid occurred with formation of 7,8-epoxy-derivatives and 7α-hydroxydihydrosandaracopimarate. The latter in addition to 7-oxotetrahydroisopimarate were formed through the action of t-butylhydroperoxide in the presence of MoCl5. Oxidation of dihydroisopimaric acid or the ester by selenium dioxide in dioxane gave the corresponding 14α-hydroxy-derivatives. Pyridinium chlorochromate transformed 14α-hydroxydihydroisopimarate into a mixture of methyl esters of 7α-hydroxy-8,14-epoxyisopimaric, 7-oxo-8,14-epoxyisopimaric, 7-oxo-14-hydroxyisopimaric, and 7α-hydroxysandaracopimaric acids. Oximation of methyl 7-oxotetrahydroisopimarate by hydroxylamine hydrochloride in MeOH in the presence of NaOAc gave a mixture of the corresponding (Z)- and (E)-oximes. Beckmann rearrangement of the 7-(E)-oxime of methyl tetrahydroisopimarate through the action of thionylchloride led to tetradecahydrodibenzo[b,d]azepine.

13-Aryl-substituted derivatives of the germacranolide argolide were synthesized by a Heck reaction with arylhalides. The structure of (E)-13-(4-methoxyphenyl)-3-oxogermacra-1(10),11(13)-dien-6α,12-olide was proved by an x-ray crystal structure analysis. Analgesic activity was found in the acetic-acid writhing test for the 13-arylgermacranolides.

New derivatives of betulin, betulinic acid methyl ester, and their acetate analogs containing 1,2,3-triazole fragments in the C-30 position were synthesized. It was shown using the Ames test that 30-azidolup-20(29)-enes and 3β,28-diacetoxy-30-(4-R-1,2,3-triazol-1-yl)lup-20(29)-enes did not exhibit mutagenic properties.

N-Aryloxyalkylanabasine derivatives were prepared via the reaction of anabasine hydrochloride with various aryloxyhaloalkanes in the presence of potash in DMF. The reaction occurred with retention of the chiral center C-(2) of the piperidine group. Side products of bis(aryloxy)ethanes were characterized.

Plants of the genus Peucedanum attract the attention of researchers as sources of coumarins. We isolated previously from P. terebinthaceum Fischer et Turcz. of Mongolia flora the pyranocoumarin (+)-pteryxin [1]. Plants of the species Ferulopsis hystrix Bunge (P. hystrix) were characterized as sources of angular furocoumarins [2]. The species P. baicalense (Redow.) Koch is broadly distributed over Mongolia [3]. Peucedanin, imperatorin, isoimperatorin, fellopterin, deltoin, bergapten, and 8-hydroxy-5-methoxypsoralen were previously isolated from its roots [3]. We studied compounds extracted from P. baicalense collected in Baruunburen, Selenge Province, Mongolia, during budding-flowering. The concentrated EtOH extract of subterranean organs was diluted with H2O. Coumarins were extracted sequentially by hexane (1.15% yield), Et2O (0.33%), and EtOAc (2.28%). An analysis of PMR spectra of the fractions showed that the principal components of the hexane extract were diacetylene compounds, coumarins (~30%), and sterols (~12%). Extracted compounds were separated by column chromatography over silica gel. Chromatography of the hexane extract (2.4 g) isolated sequentially the diacetylene alcohol falcarinol (1) and pure linear furocoumarins isoimperatorin (2) (0.032% of raw material weight), fellopterin (3) (0.038%), and 8-(1,1-dimethylallyloxy)bergapten (4) (0.044%).

Derivatives of lappaconitine containing styryl, hetarylvinyl, 3-oxobutenyl, and acetyl substituents on the aromatic ring were synthesized using a Heck reaction of 5′-iodolappaconitine and various olefines.

It was shown that plants of the genus Ferulopsis are valuable sources of coumarins. Nine angular 8-substituted and 8,9-disubstituted 8,9-dihydrofurocoumarins were isolated. The cytotoxicity of these compounds was studied on models of human CEM-13, MT-4, and U-937 tumor cells. X-ray structure data were obtained for peucenidin.

Chloro-containing compounds, the ratio of which depended on the reaction time, were formed via reaction of isoalantolactone and CHCl3 through the action of a phase-transfer catalyst. 4,15-(2,2-Dichlorocycloprop1-yl)isoalantolactone exhibited high activity and selectivity in the Heck reaction with arylhalides. Data for the cytotoxicity of the synthesized chloro-derivatives of isoalantolactone in CEM-13, MT-4, and U-937 cell tumor models were obtained. The doses of the most active compounds inhibiting the viability of tumor cells by 50 % (CCID50) were 3.2–11.1 1 M.

Allylic oxidation of phlomisoic acid and its methyl ester by selenium dioxide occurred stereoselectively to form 7α-hydroxy derivatives of labdanoids, which were oxidized by active manganese dioxide to 7-ketofuranolabdanoids. Oximation of the last by hydroxylamine hydrochloride in MeOH in the presence of NaOAc gave pure (E)-ketooximes. Beckmann rearrangement of 7-ketooximes of phlomisoic acid and its methyl ester occurred with formation of the corresponding octahydro-1 H-benzoazepines.

13-Aryl-substituted tourneforin derivatives were synthesized via the Heck reaction with aryliodides. The structure of (E)-13-(3,4-dimethoxybenzyl)-eudesma-4(5),11(13)-dien-6α,12-olide was confirmed by an XSA. A study of the cytotoxicity of the synthesized derivatives for CEM-13, MT-4, and U-937 tumor models showed promise for the modification.

The Pd-catalyzed arylation of isoalantolactone by deoxyvasicinone and lappaconitine halides occurred with formation mainly of cross-coupling products with the (E)-configuration of the double bond. Another three compounds were isolated from the reaction of isoalantolactone with 6-bromodeoxyvasicinone. These were the lactone diarylation product, a compound with the (Z)-configuration of the double bond, and a product with a shift of the C(11,13) double bond and configuration inversion at C(8). The new compounds are interesting as potential biologically active agents.

Nitro-derivatives of lappaconitine were synthesized for the first time by nitration of the alkaloid and its 5′-bromo-derivative using a trifluoroacetic acid and potassium nitrate nitrating mixture. Reduction of the nitro-derivatives by Sn(II) chloride in HCl produced the corresponding amino-derivatives of N-deacetyllappaconitine.

Chloro—and bromhydrin derivatives of the sesquiterpene lactone ludartin were synthesized for the first time. Their structures were established by spectral data and an x-ray structure analysis.

A method for preparing 15,16-epoxylabda-8(9),13(16),14-trien-18-oic (phlomisoic) acid was proposed. Its structure was confirmed by an XSA. N-containing derivatives of phlomisoic acid that contained amines, hydrazides, and methyl esters of amino acids on the C-18 atom in addition to (2-oxo-2-aminoacetyl)-substituted derivatives of the C-16 methyl ester of phlomisoic acid were prepared.

Epoxy derivatives of the sesquiterpene lactones ludartin and tourneforin were synthesized. Their structures were elucidated using spectral data and x-ray structure analysis.

Bromination of peucedanin by various reagents was studied. Conditions for forming 2-(1,3-dibromopropan-2-ylidene)-2H-furo[3,2-g][1]benzopyran-3,7-dione were found. Several 2-aminofuranocoumarins were synthesized by reaction of 2-bromoreoselone with derivatives of pyrrolidine, piperidine, and piperazine. The new compounds were interesting as potential biologically active compounds.

The potentially medically valuable pyranocoumarin (+)-pteryxin was isolated for the first time from Peucedanum terebinthaceum Fischer et Turcz. The structure of (+)-pteryxin was rigorously proved using mass spectrometry, NMR, IR, and UV spectroscopy and comparison of the spectral characteristics of this compound and its basic hydrolysis products (+)-cis- and (−)-trans-khellactone and angelic and acetic acids.

Betulonic acid amides of interest as potential biologically active compounds were prepared.

New N-acylates of the norditerpenoid alkaloid N-deacetyllappaconitine that were modified in the aromatic ring and are interesting as potential pharmacologically valuable compounds were prepared.

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.

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.

Oximation of oreoselone to produce a mixture the E- and Z-oximes was investigated. The crystal and molecular structures of oreoselone Z-oxime and the Beckmann rearrangement product of oreoselone E- or Z-oximes and PCl5, 7-(1-chloro-2-methylpropoxy)-2-oxo-2H-1-benzopyran-6-carbonitrile, were established by XSA. Hydrolysis of the latter produced 7-hydroxy-2-oxo-2H-1-benzopyran-6-carbonitrile.

New derivatives of betulin and betulinic acid containing various amines on C-30 that are of interest as potentially biologically active agents were prepared.

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.

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.

Electrocatalytic reduction of the alkaloids anabasine and nicotine was investigated. 1-α,β′-Dipiperidyl and hexahydronicotine were prepared. The reactions of anabasine and the hydrogenated alkaloids with dicarboxylic acid anhydrides were studied.

New derivatives of betulonic acid containing on C-28 fragments of amino acids or their methyl esters were prepared as potential biologically active agents.

New derivatives of betulonic and betulinic acids with 1,3,4-oxadiazole substituents in the C-17 position were prepared. The cytotoxic activity of the betulonic acid derivatives was studied using MT-4, CEM-13, and U-937 human tumor cell models.

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).

The composition of phenolic components of roots and rhizomes ofGlycyrrhiza uralensisFisch. from Siberia is studied. A total of 15 components belonging to 8 structural types including 4' -methylglucoliquiritigenin, which was previously unknown in licorices, is found. The components in samples collected from various regions of Siberia are practically identical.

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 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 bromination of betulin with bromine was descibed. The reaction in chloroform proceeded smoothly to form 29,30-dibromoallobetulin in 80% yield.

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.

Vasicinone and peganine were isolated from Peganum harmala L. Vasicinone 2,4-dinitrophenylhydrazone and vasicinone ketal were prepared.

(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.

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.