A new sesquiterpenoid from Sclerorhachis platyrachis (Boiss.) Podlech ex Rech.f

A new eudesmane-type sesquiterpenoid together with two known flavonoids were isolated from the chloroform extract of the aerial part of Sclerorhachis platyrachis. The structure of the new compound was deduced from its comprehensive spectroscopic analysis including IR, EI-MS, ¹H NMR, ¹³C NMR, DEPT, COSY, HMBC and HMQC and was shown to be 4R^*-hydroxy-6S^*-tigloyloxyeudesma-7S^*-11 (13)-en-12-oic acid (1). Finally, the structure of the new compound was unambiguously confirmed by single-crystal X-ray analysis. The structure of known compounds 2 and 3 were identified by comparison of their spectral data with those reported in the literature.     

Thiobacillus sajanensis sp. nov., a new obligately autotrophic sulfur-oxidizing bacterium isolated from Khito-Gol hydrogen-sulfide springs, Buryatia

Four strains of rod-shaped gram-negative sulfur-oxidizing bacteria were isolated from Khoito-Gol hydrogen-sulfide springs in the eastern Sayan Mountains (Buryatia). The cells of the new isolates were motile by means of a single polar flagellum. The strains were obligately chemolithoautotrophic aerobes that oxidized thiosulfate (with the production of sulfur and sulfates) and hydrogen sulfide. They grew in a pH range of 6.8–9.5, with an optimum at pH 9.3 and in a temperature range of 5–39°C, with an optimum at 28–32°C. The cells contained ubiquinone Q-8. The DNA G+C content of the new strains was 62.3–64.2 mol %. According to the results of analysis of their 16S rRNA genes, the isolates belong to the genus Thiobacillus within the subclass Betaproteobacteria. However, the similarity level of nucleotide sequences of the 16S rRNA genes was insufficient to assign the isolates to known species of this genus. The affiliation to the genus Thiobacillus was confirmed by DNA-DNA hybridization of the isolates with the type strain of the type species of the genus Thiobacillus, T. thioparus DSM 505^T (= ATCC 8158^T). Despite the phenotypic similarity, the hybridization level was as low as 21–29%. In addition, considerable differences were revealed in the structure of the genes encoding RuBPC, the key enzyme of autotrophic CO₂ assimilation, between the known Thiobacillus species and the new isolates. Based on molecular-biological features and certain phenotypic distinctions, the new isolates were assigned to a new Thiobacillus species, T. sajanensis sp. nov., with the type strain 4HG^T (= VKM B-2365^T).     

Zwei neue germacranolide aus Artemisia argentea

The aerial parts of Artemisia argentea afforded, in addition to known compounds (arborescin, artemetin, sitosterol and lirioresinol-B-dimethyl ether), two new germacranolides, closely related to ketopelenolide, also isolated from an Artemisa species. The structures were elucidated by intensive ¹H NMR studies and by some chemical transformations.     

Obliquin derivatives and other constituents from Australian Helichrysum species

The investigation of three Australian Helichrysum species afforded in addition to known compounds three new obliquin derivatives, eight cinnamic acid derivatives, a tremetone derivative, a styrene derivative, two lignans, two caryophyllene derivatives and an azulene. The structures were elucidated by highfield ¹H NMR.     

11β,13-Dihydroguaianolides from Artemisia douglasiana and a thiophene acetylene from A. schmidtiana

The aerial parts of Artemisia douglasiana afforded, in addition to some known sesquiterpene lactones, 22 new closely related guaianolides. A new thiophene acetylene was isolated from the aerial parts of A. schmidtiana together with some known sesquiterpene lactones. The structures were elucidated by high field ¹H NMR spectroscopy.     

Eudesman-12,8β-olides and other terpenes from Artemisia species

The aerial parts of Artemisia iwayomogi afforded, in addition to already known terpenes, eleven new cudesmanolides whereas four new guaianolides were found in A. gmelinii. No sesquiterpene lactones were detected in the aerial parts of A. santolinifolia which afforded two new nerolidol derivatives besides several other already known compounds. From A. caerulescens var. cretacea six eudesmanolides were isolated, one of which has not been reported previously. The structures were elucidated by high field ¹H NMR spectroscopy and chemical transformations. The chemotaxonomic significance of sesquiterpene lactones within the section Abrotanum and the subgenus Seriphidium is briefly discussed.     

New germacranolides and other sesquiterpene lactones from Dicoma species

Two subspecies of Dicoma anomala afforded, in addition to known compounds, an eudesmanolide, a guaianolide and four germacranolides, the latter being closely related 8, 12-lactones. D. schinzii gave three new germacranolides and D. zeyheri a pair of isomeric acetylenic compounds. The structures were elucidated by highfield ¹H NMR spectroscopy. The chemotaxonomic situation of this genus is discussed briefly.     

Cytotoxic components of Zingiber zerumbet,Curcuma zedoaria and C. domestica

One new and five known compounds, which all showed cytotoxic activity, were isolated from the rhizomes of Zingiber zerumbet. The new compound was 3″,4″-O-diacetylafzelin. The known compounds were zerumbone, zerumbone epoxide, diferuloylmethane, feruloyl-p-coumaroylmethane and di-p-coumaroylmethane. Several substituted cinnamoylmethanes were synthesized and tested for cytotoxic properties. Among these were tricinnamoylmethane and triferuloylmethane. The structures were elucidated mainly by spectroscopic methods and ¹³C NMR data are given.     

Synthesis of the facteur thymique serique and an analog also related to thymopoietin

The known 9-amino-acid sequence of the facteur thymique serique (FTS) and the known 49-amino-acid sequence of thymopoietin, in conjunction with background peptide chemistry, raised the possibility that Gln¹ of FTS might be linked to Arg⁴⁹ of thymopoietin in a new 58-amino-acid peptide in tissue. A presumed cleavage between Gln⁵⁰ and Arg⁴⁹ adjacent to the Lys⁴⁸-Arg⁴⁹ moiety would liberate [H-Gln¹]-FTS and thymopoietin; the former fragment would cyclize to FTS by known chemistry. To study this possibility, FTS, and a new dodecapeptide consisting of Val-Lys-Arg linked to the N-terminal of [H-Gln¹]-FTS were synthesized on a new solid-phase resin and were found to show comparable immune stimulating activity, in vivo. These data do not negate, but support, the concept of the 58-aminoacid peptide.     

Sesquiterpenes and acetylenes from Argyranthemum adauctum ssp. jacobaeifolium

The roots of Argyranthemum adauctum ssp. jacobaeifolium, a rare endemic from Gran Canaria, afforded two new derivatives of the aromatic acetylene frutescin and 8-isovaleryloxymyrcene, while the aerial parts gave a new bisabolol derivative. Furthermore several known compounds were isolated. The structures were elucidated by high field ¹H NMR spectroscopy and a few chemical reactions.     

Sesquiterpene lactones and diterpene carboxylic acids in Helianthus niveus subspecies Canescens

Three new heliangolides (niveusin-A, -B and -C) and three known diterpene carboxylic acids were isolated and characterized from a CHCl₃, extract of Helianthus niveus. The structures of the three new lactones were deduced by ¹H and ¹³C NMR as well as extensive decoupling experiments and derivatizations.     

Tropane alkaloids from Schizanthus grahamii

Three new tropanol dimers of mesaconic and itaconic acids and 3α-senecioyloxytropane, together with other known alkaloids, were isolated from Schizanthus grahamii. The structures of the new compounds were established by spectroscopic and chemical transformations including 2-D long-range ¹³C-¹H correlations.     

Germacrene derivatives and other sesquiterpenes from Senecio species and Lordhowea insularis

From Senecio galpinii six new highly oxygenated germacrene derivatives were isolated, while S. coronatus afforded in addition to known cacalol derivatives two new ones. This species also contained a rare tricyclic sesquiterpene angelate, so far only isolated from one species. From the aerial parts of S. pleistocephalus an angelate derived from cadinene was isolated, while Lordhowea insularis (Benth.) B. Nord. afforded farnesyl angelate, which was reported previously. The structures were elucidicated mainly by high field ¹H NMR spectroscopy.     

Isolation of two new phenolic compounds from the fruit of Chaenomeles speciosa (Sweet) Nakai

Phytochemical research on the anti-inflammatory activities of Chaenomeles speciosa (Sweet) Nakai (Rosaceae) to investigate the main components of 10% ethanol fraction of the crude extract of C. speciosa fruit in an attempt to find bioactive compounds or new compounds from this medicinal plant. The phytochemical investigation succeeded in isolating two new phenolic compounds, specpolyphenol A (1) and specphenoside A (2), together with three known phenyl glycosides (3–5) from the fraction. The structures of the new compounds were deduced from comprehensive spectroscopic analyses including IR, EI-MS, ¹H NMR, ¹³C NMR, DEPT, COSY, HMBC and HMQC. The structures of the three known compounds 3, 4 and 5 were identified by comparison of their spectral data with those reported in the literature.     

New siphulin derivatives from the lichen Siphula ceratites

From the lichen, Siphula ceratites, two new metabolities, protosiphulin and oxysiphulin, were isolated besides the known compound, siphulin. The structures of the two new chromenones were proved by ¹H NMR and ¹³C NMR spectral analysis in comparison with those of siphulin.     

Bioactive styryllactones,two new naphthoquinones and one new styryllactone,and other constituents from Goniothalamus scortechinii

Two new naphthoquinones, goniothalaminone A (1) and B (2), and a new styryllactone, (?)-8-epi-9-deoxygoniopypyrone acetate (12) together with one known naphthoquinone (3), one known indolequinone (4), one known 1-azaanthraquinone (5), six known styryllactones (6–11) and one known sesquiterpene (13) were isolated from the roots and leaves of Goniothalamus scortechinii. The structures of the new compounds were elucidated by spectroscopic analysis and of the known compounds by comparison of their physical, UV, IR, ¹H and ¹³C NMR data with those of published compounds. Antiplasmodial, antimycobacterial and cytotoxic activities of the styryllactones were evaluated. Compounds 6–10 exhibited cytotoxic against human cancer cell lines, KB, BC and NCI-H187 with IC₅₀ values ranging from 0.13 to 11.7 μg/ml.     

Caryophyllene derivatives and a hydroxyisocomene from Pulicaria dysenterica

The investigation of the aerial parts of Pulicaria dysenterica afforded, in addition to known compounds, nine new caryophyllene derivatives with oxygen functions at C-7, C-13 and either C-14 or C-5. One of the keto diols was also present as an ester of a caryophyllenic acid. The roots afforded a new derivative of isocomene together with its precursor. The structures were elucidated by highfield ¹H NMR spectroscopy and by some chemical transformations.     

Types of sesquiterpene-coumarin ethers from Achillea ochroleuca and Artemisia tripartita

In addition to known derivatives, four new sesquiterpene-coumarin ethers were isolated from the roots of Achillea ochroleuca and Artemisia tripartita and identified by ¹H and ¹³C NMR spectroscopy, including lanthanide induced shifts. The new compounds are isofraxidin derived ethers which differ from the previously described derivatives by ring cleavage and methyl migration within the terpenoid unit. The chemosystematic importance of sesquiterpene-coumarin ether accumulation within the two genera is briefly discussed.     

Isoprenylated flavonoids from the roots of Sophora tonkinensis

Two new isoprenylated flavanones, tonkinochromanes J (1) and K (2), and a new isoprenylated dihydrochalcone, tonkinochromane L (3), were isolated from the roots of Sophora tonkinensis along with four known compounds (4-7). Their structures were determined by means of spectroscopic analyses, including HRMS, IR, ¹H and ¹³C NMR and 2D experiments (COSY, HSQC, and HMBC), and comparison with known related compounds.     

Sesquiterpene lactones from Montanoa gigas and the crystal structure of gigantanolide a

Chemical analysis of Montanoa gigas afforded in addition to known kaurane-derivatives three new 12,6-cis-germacrolides named gigantanolides, A, B and C. The structures of the new compounds were established by spectral methods mainly ¹H NMR. The structure of gigantanolide A was confirmed by single crystal X-ray diffraction.