- The Occurrence of Some Novel Diesters in Roman Camomile Oil
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Three diols, 2-methylidene-1,3-propanediol, 2-methyl-1,3-propanediol and 1,3-butanediol, esterified on one hydroxyl group with isobutyric acid and on the other with angelic acid), have been isolated from Anthemis nobilis oil (Roman camomile) an synthesized.The presence of homologous esters is very probable.
- Thomas, Alan F.
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- Bioactive saponins and glycosides part 29. Acylated oleanane-type triterpene saponins: Theasaponins A6, A7, and B 5 from the seeds of Camellia sinensis
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Three new acylated oleanane-type triterpene saponins, theasaponins A 6 (1), A7 (2), and B5 (3), were isolated from the saponin fraction of the seeds of the Japanese tea plant Camellia sinensis together with the known constituent foliatheasaponin III (4). The structures of the glycosides 1-3 were elucidated on the basis of spectroscopic, chemical, and physico-chemical evidence.
- Morikawa, Toshio,Matsuda, Hisashi,Li, Ning,Li, Xian,Yoshikawa, Masayuki
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- Chromones and coumarins from Saposhnikovia divaricata (Turcz.) Schischk. Growing in Buryatia and Mongolia and their cytotoxicity
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Ethnopharmacological relevance: Saposhnikovia divaricata (family Apiaceae) a traditional medicinal plant distributed in many provinces of China, is well known for the pharmaceutical value and has been used for rheumatic arthritis, and anxiety in children. Antiviral, antioxidant and antiproliferative activities were also mentioned. The application of this plant are recorded in the Chinese Medicine (CM) classical text the Shen Nong's Materia Medica (Shen Nong Ben Cao Jing). In this monograph S. divaricata (syn Radix Ledebouriella divaricata) is graded as a premium-grade herb, with their broad-spectrum of therapeutic applications for the treatment of cough, common cold, arthralgia, as well as in rheumatic disorders. Aim of the study: To isolate and identify chemical constituents (chromones and coumarins) from S. divaricata, collected in Buryatia and Mongolia and to study their in vitro anticancer activity against MEL-8, U-937, DU-145, MDA-MB-231 and ВТ-474 cell lines. Materials and methods: An 40% aqueous ethanol extract of the roots of S. divaricata was prepared and further successively fractionated by extraction with petroleum ether, diethyl ether, tert-butyl methyl ether and ethyl acetate. The obtained extracts were subjected to a series of chromatographic separations on silica gel for isolation of individual compounds. Isolated compounds were tested for their cytotoxicity with respect to model cancer cell lines using the conventional MTT assays. Results: Total of 15 individual compounds: coumarins scopoletin 2, bergapten 3, isoimperatorin 4, marmesin 5, (+)-decursinol 9, (?)-praeruptorin B 10, oxypeucedanin hydrate 11, chromones: hamaudol 6, cimifugin 7, 5-О-methylvisamminol 8, chromone glycosides: prim-O-glucosylcimifugin 12, sec-O-glucosylhamaudol 13, 4′-O-β-D-glucopyranosyl-5-О-methylvisamminol 14, 4′-O-β-D-glucopyranosylvisamminol (15) and also polyyne compound panaxinol 1 were isolated and characterized. The structure of dihydropyranocoumarin 10 was confirmed by X-ray diffraction analyses. HPLC-UV method was used for determination of the content of most abundant chromones 7, 12 and 14 in the roots of S. divaricata, collected in Mongolia. Compounds 3–11 and 13, 14 were evaluated for their cytotoxicity with respect to model cancer cell lines. All the compounds were non-toxic in the hemolysis test. Conclusion: This report about the phytochemical profiles of S. divaricata growing in Mongolia and Buryatia led to the identification of 14 compounds including coumarins and chromones. The available coumarins and chromones may serve as new leads for the discovery of anticancer drugs.
- Frolova, Tatyana S.,Ganbaatar, Jamsranjav,Petrova, Tatyana N.,Pokrovskii, Andrey G.,Radnaeva, Larisa D.,Rybalova, Tatyana V.,Shults, Elvira E.,Taraskin, Vasilii V.,Urbagarova, Bayarma M.
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- Dienolates of Cycloalkenones and α,β-Unsaturated Esters Form Diels–Alder Adducts by a Michael/Michael-Tandem Reaction Rather Than in One Step
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α,β-Unsaturated esters and lithium 1,3-dien-2-olates are known to furnish bicyclic lithium enolates by anionic Diels–Alder reactions. However, in principle, the respective products might form not only in a single step but also in two consecutive – or “tandem” – Michael additions, the first of which occurs intermolecularly, the second intramolecularly. Three cyclic lithium dienolates and four esters with a stereogenic Cα=Cβ bond reacted to give Diels–Alder adducts (10 times) or failed to react (2 times). Seven of the reactive combinations furnished adducts wherein the configuration of the former ester moiety had in part inverted. This precludes concerted pathways as their origins. This was a surprise since donors at C-2 of the 1,3-diene accelerate normal electron-demand Diels–Alder reactions in the order alkyl ⊕O? being a far better donor still, it is not obvious why the mechanism is non-concerted rather than concerted (and still more asynchronous).
- Loesche, Ann-Christine,Brückner, Reinhard
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supporting information
p. 562 - 573
(2018/12/11)
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- Sodium Methyl Carbonate as an Effective C1 Synthon. Synthesis of Carboxylic Acids, Benzophenones, and Unsymmetrical Ketones
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Reported is the synthesis of carboxylic acids, symmetrical ketones, and unsymmetrical ketones with selectivity achieved by exploiting the differential reactivity of sodium methyl carbonate with Grignard and organolithium reagents.
- Hurst, Timothy E.,Deichert, Julie A.,Kapeniak, Lucas,Lee, Roland,Harris, Jesse,Jessop, Philip G.,Snieckus, Victor
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supporting information
p. 3882 - 3885
(2019/06/07)
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- Asymmetric dihydroxylation of esters and amides of methacrylic, tiglic, and angelic acid: No exception to the sharpless mnemonic!
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Literature findings on the facial selectivity of the Sharpless asymmetric dihydroxylation (SAD) of isobutyl angelate are contradictory and partly in conflict with the Sharpless mnemonic. We systematically screened the SAD of esters and amides of angelic, tiglic, and methacrylic acid. Enantiocontrol arose in 14 of the 15 reactions, culminating at 99 % ee for the Weinreb amide of tiglic acid. The absolute configurations of all the nonracemic products were established by (stereo)chemical correlations. Without exception, they conform to the Sharpless mnemonic.
- Weber, Fabian,Brückner, Reinhard
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p. 2428 - 2449
(2015/04/22)
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- Resin glycosides from Porana duclouxii
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A new intact resin glycoside (3) and two glycosidic acids (1 and 2), all having a common trisaccharide moiety and (11S)-hydroxytetradecanoic acid or (3S,11S)-dihydroxytetradecanoic acid as the aglycone, were obtained from the roots of Porana duclouxii. Their structures were elucidated by spectroscopic analyses and chemical correlations. These compounds represent the first examples of resin glycosides from the genus Porana.
- Ding, Wen-Bing,Zhang, Dai-Gui,Liu, Chun-Jie,Li, Guan-Hua,Li, You-Zhi
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p. 135 - 140
(2014/02/14)
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- Palladium-catalyzed synthesis of aromatic carboxylic acids with silacarboxylic acids
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Aryl iodides and bromides were easily converted to their corresponding aromatic carboxylic acids via a Pd-catalyzed carbonylation reaction using silacarboxylic acids as an in situ source of carbon monoxide. The reaction conditions were compatible with a wide range of functional groups, and with the aryl iodides, the carbonylation was complete within minutes. The method was adapted to the double and selective isotope labeling of tamibarotene.
- Friis, Stig D.,Andersen, Thomas L.,Skrydstrup, Troels
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supporting information
p. 1378 - 1381
(2013/04/24)
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- Medicinal flowers. XXXVI.1) Acylated oleanane-type triterpene saponins with inhibitory effects on melanogenesis from the flower buds of Chinese Camellia japonica
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Four acylated oleanane-type triterpene oligoglycosides, sanchakasaponins E-H, were isolated from the flower buds of Camellia japonica cultivated in Yunnan province, China, together with four known triterpene oligoglycosides. The chemical structures of the new triterpene oligoglycosides were elucidated on the basis of chemical and physicochemical evidence. The inhibitory effects of the triterpene oligoglycoside constituents on melanogenesis in theophylline-stimulated B16 melanoma 4A5 cells were investigated.
- Nakamura, Seikou,Fujimoto, Katsuyoshi,Nakashima, Souichi,Matsumoto, Takahiro,Miura, Tomoko,Uno, Kaoru,Matsuda, Hisashi,Yoshikawa, Masayuki
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experimental part
p. 752 - 758
(2012/09/25)
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- Sesquiterpenes from Blumea balsamifera
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Five new guaiane sesquiterpenes, blumeaenes E1 (1), E2 (2), K (3), L (4), and M (5), and one new eudesmane sesquiterpene, samboginone (6), along with three known compounds, cryptomeridiol, 3,3′,5,7-tetrahydroxy-4′- methoxyflavanone, and austroinulin, were isolated from the leaves of the Philippine medicinal herb sambong, Blumea balsamifera. The absolute configuration of the new guaiane core was determined as 1S,7S,9S,10R by employing the modified Mosher's method. In the structure of 1, the absolute configuration of the epoxyangelic acid moiety was identified as 2S,3S using (R)-PGME as a chiral anisotropic auxiliary.
- Shirota, Osamu,Oribello, Jennifer M.,Sekita, Setsuko,Satake, Motoyoshi
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experimental part
p. 470 - 476
(2011/05/30)
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- Medicinal flowers. XXX. Eight new glycosides, everlastosides F - M, from the flowers of Helichrysum arenarium
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Eight new glycosides, everlastosides F (1), G (2), H (3), I (4), J (5), K (6), L (7), and M (8), were isolated from the methanolic extract of the flowers of Helichrysum arenarium. Their structures were elucidated on the basis of chemical and physicochemic
- Morikawa, Toshio,Wang, Li-Bo,Ninomiya, Kiyofumi,Nakamura, Seikou,Matsuda, Hisashi,Muraoka, Osamu,Wu, Li-Jun,Yoshikawa, Masayuki
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experimental part
p. 853 - 859
(2010/03/26)
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- Plant Coumarins. 3. (-temp)-PTeryxin from Peucedanum terebinthaceum
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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 c
- Ganbaatar,Gantumur,Osadchii,Shul'ts,Shakirov,Tolstikov
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experimental part
p. 578 - 581
(2009/04/07)
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- Total synthesis of thiostrepton. Retrosynthetic analysis and construction of key building blocks
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The first phase of the total synthesis of thiostrepton (1), a highly complex thiopeptide antibiotic, is described. After a brief introduction to the target molecule and its structural motifs, it is shown that retrosynthetic analysis of thiostrepton reveals compounds 23, 24, 26, 28, and 29 as potential key building blocks for the projected total synthesis. Concise and stereoselective constructions of all these intermediates are then described. The synthesis of the dehydropiperidine core 28 was based on a biosynthetically inspired aza-Diels-Alder dimerization of an appropriate azadiene system, an approach that was initially plagued with several problems which were, however, resolved satisfactorily by systematic investigations. The quinaldic acid fragment 24 and the thiazoline-thiazole segment 26 were synthesized by a series of reactions that included asymmetric and other stereoselective processes. The dehydroalanine tail precursor 23 and the alanine equivalent 29 were also prepared from the appropriate amino acids. Finally, a method was developed for the direct coupling of the labile dehydropiperidine key building block 28 to the more advanced and stable peptide intermediate 27 through capture with the highly reactive alanine equivalent 67 under conditions that avoided the initially encountered destructive ring contraction process.
- Nicolaou,Safina, Brian S.,Zak, Mark,Lee, Sang Hyup,Nevalainen, Marta,Bella, Marco,Estrada, Anthony A.,Funke, Christian,Zecri, Frederic J.,Bulat, Stephan
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p. 11159 - 11175
(2007/10/03)
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- PREPARATION OF (E)- AND (Z)-2-METHYL-2-BUTENOIC ACIDS
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A method has been developed to prepare (E)- and (Z)-2-methyl-2-butenoic acids (2M2BA) from a mixture of (E,Z)-2-methyl-2-butenenitriles (2M2BN) by the regioselective hydrolysis of (E)-2M2BN to (E)-2-methyl-2-butenoic acid (2M2BA) using enzyme catalysts having either a nitrilase activity or a combination of nitrile hydratase and amidase activities. The method provides high yields without significant conversion of (Z)-2M2BN to (Z)-2M2BA. The regioselective hydrolysis of (E)-2M2BN to (E)-2M2BA makes possible the facile separation of (E)-2M2BA from (Z)-2M2BN or (Z)-2-methyl-2-butenamide (2M2BAm), and the subsequent conversion of (Z)-2M2BN or (Z)-2M2BAm to (Z)-2M2BA.
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- Synthetic studies on thiostrepton: Construction of thiostrepton analogues with the thiazoline-containing macrocycle
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Leading the way: The novel thiostrepton analogue 1 and its 5S, 6S diastereomer were synthesized through macrolactamization reactions. Forays towards the total synthesis of the natural product itself should follow a similar strategy.
- Nicolaou,Nevalainen, Marta,Zak, Mark,Bulat, Stephan,Bella, Marco,Safina, Brian S.
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p. 3418 - 3424
(2007/10/03)
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- STRUCTURE AND STEREOCHEMISTRY OF FERTIDIN
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The new ester, fertidin, has been isolated from the phenolic fraction of Ferula tenuisecta, and on the basis of chemical transformations and spectral characteristics its structure and stereochemistry have been established as 10α-angeloyloxy-4β-hydroxy-6α-p-hydroxybenzoyloxycarot-(9)-ene.
- Saidkodzhaev, A. I.,Golovina, L. A.,Malikov, V. M.
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p. 701 - 703
(2007/10/02)
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- New Stereoselective Approach to Hydroxy-Substituted Tetrahydrofurans. Total Synthesis of (+/-)-Citreoviral
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A concise total synthesis of (+/-)-citreoviral which illustrates a new stereoselective approach to hydroxy-substituted tetrahydrofurans is described.Key features in the synthesis are: (i) elaboration of the Z-unsaturated epoxy ester 10, (ii) acid-catalysed cyclisation of ester 10 to the 4-hydroxyethyl-substituted but-2-enolide 14, (iii) stereoselective vicinal hydroxylation of the butenolide 14 to the diol 15, (iv) cyclic ether formation from diol 15 to the bicyclic lactone 8 via the benzylidene acetal 9, (v) transesterification of bicycle 8 to the tetrahydrofuran 21 containing three of the four centres in citreoviral in the correct relative configuration.Inversion of the secondary 3-OH group in compound 21, and elaboration of the C-2 side-chain, then completed the synthesis of (+/-)-citreoviral.
- Begley, Michael J.,Bowden, Martin C.,Patel, Prakash,Pattenden, Gerald
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p. 1951 - 1958
(2007/10/02)
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- TOTAL SYNTHESIS OF (+)-CITREOVIRAL
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A total synthesis of (+)-citreoviral (1) found in Penicillium citreoviride, which uses the bicyclic lactone (5) as a key intermediate, is described.
- Bowden, Martin C.,Pattenden, Gerald
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p. 711 - 714
(2007/10/02)
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- ENT-LABDANE DERIVATIVES FROM GUTIERREZIA GRANDIS
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Key Word Index - Gutierrezia grandis; Compositae; Astereae; ent-labdane derivatives; 3α-angeloyloxy-18-hydroxy-13-furyl-ent-labda-8(17)-ene; 3α-hydroxy-18-angeloyloxy-13-furyl-ent-labda-8(17)-ene; 3α,18-dihydroxy-13-furyl-ent-labda-8(17)-ene. - Two new diterpenes, 3α-angeloyloxy-18-hydroxy-13-furyl-ent-labda-8(17)-ene and 3α-hydroxy-18-angeloyloxy-13-furyl-ent-labda-8(17)-ene and an only recently reported third diterpene, 3α,18-dihydroxy-13-furyl-ent-labda-8(17)-ene, were isolated from the leaves of Gutierrezia grandis.Their structures were determined by mass spectral, IR, 1H NMR and 13C NMR data as well as chemical evidence.
- Gao, Feng,Leidig, Mark,Mabry, Tom J.
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p. 1541 - 1544
(2007/10/02)
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- PHENYLPROPANOIDS AND OTHER DERIVATIVES FROM THAPSIA VILLOSA
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Key Word Index - Thapsia villosa; Umbelliferae; roots; phenylpropanoids; hemanticine; guaianolides; thapsivillosin K. - Five phenylpropanoids related to hemanticine have been obtained from Thapsia villosa roots.We propose for these substances the trivial names isohelmanticine, neohelmanticine, isoneohelmanticine, epoxyhelmanticine and epoxyhelmanticine angelate.All these substances are based on (1S,2R)1-(3-methoxy-4,5-methylenedioxyphenyl)-1,2-propanediol, which is esterified variously by acetic, angelic, epoxyangelic and/or (2R,3S)2,3-dihydroxy-2-methylbutyric acids.We also report three C6-guaianolides and their hydrolysis products.The name thapsivillosin K is proposed for a new guaianolide.
- Teresa, J. De Pascual,Moran, Joaquin R.,Hernandez, Jose M.,Grande, M.
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p. 2071 - 2074
(2007/10/02)
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- HELMANTICINE, A PHENYLPROPANOID FROM THAPSIA VILLOSA
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Helmanticine, a new phenylpropanoid esterified by angelic and 2,3-dihydroxy-2-methylbutyric acids, was isolated from Thapsia villosa and its full structure established by spectroscopic methods and chemical transformations.Hydrocarbons, 12-nonacosanone, sitosterol and latifolone were also isolated. Key Word Index - Thapsia villosa; Umbelliferae; phenylpropanoids; helmanticine; latifolone; 12-nonacosanone.
- Teresa, Joaquin de Pascual,Pascual, Marian de,Arias, Alicia,Hernandez, Jose M.,Moran, Joaquin R.,Grande, Manuel
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p. 1773 - 1778
(2007/10/02)
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- FARFUGINE, A NEW PYRROLIZIDINE ALKALOID ISOLATED FROM FARFUGIUM JAPONICUM KITAM.
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A new pyrrolizidine alkaloid, farfugine (1) was isolated from Farfugium japonicum Kitam. and the structure including absolute stereochemistry was elucidated by chemical and spectroscopic evidence.
- Niwa, Haruki,Ishiwata, Hiroyuki,Kuroda, Akio,Yamada, Kiyoyuki
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p. 789 - 790
(2007/10/02)
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- STRUCTURE AND STEREOCHEMISTRY OF LAPIFERIN
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Lapiferin, C22H34O6, m.p. 137-138 deg C, 21D +63 (c 1.3; chloroform), a diester of the new carotane alcohol lapiferol with angelic and acetic acids, has been isolated from the roots of Ferula lapidosa Eug.Korov.On the basis of chemical transformations and spectral characteristics, the structure of 10α-acetoxy-6α-angeloyloxy-8α,9α-epoxy-trans-carotan-4β-ol has been proposed for it.
- Golovina, L. A.,Saidkhodzhaev, A. I.,Abdullaev, N. D.,Malikov, V. M.,Yagudaev, M. R.
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p. 281 - 285
(2007/10/02)
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- THE COUMARIN COMPOSITION OF Seseli tortuosum
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The results are given of the identification of the known pyranocoumarin campestrinol (I), and the structures of four new coumarin derivatives have been studied - tortuosin (II), tortuosinin (III), tortuosinol (IV), and tortuosidin (V).On the basis of their spectral characteristics and chemical transformations, the corresponding structures have been established for compounds (II)-(V).
- Abyshev, A. Z.,Abyshev, D. Z.
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p. 668 - 672
(2007/10/02)
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- COMPARATIVE CHARACTERIZATION OF THE COUMARIN COMPOSITION OF Seseli campestre GROWING IN MOLDAVIA AND IN THE CAUCASUS
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The results are given of the identification of (-)-trans-khellactone and its 4'-methyl ether and (-)-3'(S),4'(S)-trans-3'-senecioyloxy-4'-angeloyloxy-3',4'-dihydroseselin and of the establishment of the structure of three new khellactone derivatives - campestrol (VII), C19H22O6, D20+32 deg (c 7.8; chloroform), campestrinol (X), C24H26O7, mp 116-118 deg C, and campestrinoside (I), C20H24O10, mp 172-173 deg C, D -272.5 deg (c 4.7; ethanol).It has been shown on the basis of chemical and spectral characteristics that campesol, earlier described as a new substance, is a mixture of two isomeric compounds - 4'-hydroxy-3'-senecioyloxy-3',4'-dihydroseselin and 3'-angeloyloxy-4'-hydroxy-3',4'-dihydroseselin.
- Abyshev, A. Z.,Sidorova, I. P.,Abyshev, D. Z.,Florya, V. N.,Zmeikov, V. P.,Kerimov, Yu. B.
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p. 400 - 407
(2007/10/02)
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- LASERINE OXIDE, AN EPOXIDE FROM GUILLONEA SCABRA
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From the roots of Guillonea scabra several previously known compounds were isolated.In addition, a new epoxy derivative of laserine was obtained and its structure was established by chemical and spectroscopic means.Key Word Index - Guillonea scabra; Umbelliferae; new laserine derivative; laserine oxide.
- Pinar, Mariano,Rico, Manuel,Rodriguez, Benjamin
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p. 735 - 738
(2007/10/02)
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- STRUCTURE AND STEREOCHEMISTRY OF LAPIDIN
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The roots of Ferula lapidosa Eug.Korov. have yielded lapidin, C20H30O4, mp 80-81 deg C (hexane), 20D +166 deg (c 1.5; chloroform) - an ester of a new carotane alcohol lapidol and angelic acid.A structure and absolute configuration has been suggested for it on the basis of chemical transformations and spectral characteristics.
- Golovina, L. A.,Saidkhodzhaev, A. I.
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p. 244 - 248
(2007/10/02)
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- The Constituents of Schizandra chinensis BAILL. VIII. The Structures of Two New Lignans, Tigloylgomisin P and Angeloylgomisin
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Two new dibenzocyclooctadiene lignans, tigloylgomisin P(1), and angeloylgomisin P(2) were isolated from the fruits of Schizandra chinensis BAILL. (Schizandraceae).Their absolute structures were elucidated by means of chemical and spectral studies.Keywords - Schizandra chinensis BAILL; Schizandraceae; dibenzocyclooctadiene; lignan; tigloylgomisin P; angeloylgomisin P; NOE; (13)C-NMR
- Ikeya, Yukinobu,Taguchi, Heihachiro,Yosioka, Itiro,Kobayashi, Hiroshi
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p. 3357 - 3361
(2007/10/02)
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