- A secoiridoid and other constituents of Gonocaryum calleryanum
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Investigation of the leaves, branch, stem and root bark of Gonocaryum calleryanum resulted in the isolation of a new secoiridoid glycoside, gonocaryoside E, together with 14 known compounds. Their structures were elucidated by spectral analysis and chemical transformation. Gonocaryoside E was shown to be a derivative of kingiside in which the lactone ring was open, and with the 8-hydroxy group esterified with tiglic acid. Alkaline hydrolysis of these secoiridoids is discussed.
- Chan, Yu Yi,Leu, Yann Lii,Lin, Ful Wen,Li, Chia Ying,Wu, You Cheng,Shi, Li Shian,Liou, Meei Jen,Wu, Tian Shung
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Read Online
- Calyhedins I–VI: Resin glycosides from the rhizomes of Calystegia hederacea
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Six previously undescribed resin glycosides, calyhedins I–VI, were isolated from the rhizomes of Calystegia hederacea Wall., which are the first genuine resin glycosides isolated from C. hederacea. The structures of calyhedins I–VI were determined based on spectroscopic data and chemical evidence. All the compounds have macrolactone structures (jalapins), and their sugar moieties were partially acylated by five organic acids. Calyhedins I, II–V, and VI have 27-, 28-, and 23-membered rings, respectively, and calyhedins IV–VI are the first jalapins with a sugar chain consisting of seven monosaccharides. Additionally, the cytotoxic activity of calyhedins II and III toward HL-60 human promyelocytic leukemia cells was evaluated. Both compounds demonstrated almost the same activity as the positive control, cisplatin.
- Kinjo, Junei,Matsubara, Souta,Nohara, Toshihiro,Okawa, Masafumi,Ono, Masateru,Shimohara, Takaaki,Tsuchihashi, Ryota,Yasuda, Shin,Yoshimitsu, Hitoshi,Yuhara, Nobuyoshi,Zhou, Jian-Rong
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- Method for simply and conveniently synthesizing tiglic acid
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The invention discloses a method for simply and conveniently synthesizing tiglic acid. The method comprises the following steps: carrying out an addition reaction between a Grignard reagent and pyruvic acid or alpha-butanone acid at a normal temperature by using HMPA or DMPU as an assistant to obtain 2-hydroxy-2-methylbutyric acid, marking the 2-hydroxy-2-methylbutyric acid as an intermediate III;and then, heating the intermediate III under the action of sulfuric acid with a mass concentration of not less than 67% to carry out dehydration reaction to obtain tiglic acid. Materials which can cause serious pollution in the prior art are not used, the reaction steps are short, the technological conditions are simple, no special requirements for equipment exist, the product yield is high, andthe method is suitable for industrial production.
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Paragraph 0017; 0035; 0040; 0041
(2020/06/20)
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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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- Industrial preparation method of tiglic acid
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The invention discloses an industrial preparation method of tiglic acid. The industrial preparation method is characterized by comprising the following steps: taking sodium acid sulfate as a catalyst,preparing 3-methyl-3-pentene-2-one (formula II) by utilizing paraldehyde and butanone which are cheap and are commercially easily obtained, and carrying out haloform reaction on a compound shown as the formula II, a sodium hypochlorite water solution and a sodium hydroxide water solution in a continuous flowing reactor to prepare the tiglic acid (formula I). By adopting the method, the disadvantages in the prior art are overcome; the method has the advantages that a utilized catalyst is cheap and easy to obtain and has high catalytic activity, no corrosion to equipment and less pollution caused by three wastes; the continuous flowing reactor provides better heat efficiency and has lower energy consumption; meanwhile, compared with a kettle type stirring reactor, production procedures aresimplified, the production time is shortened, the yield of a product is high and the operation is simple; the method is more suitable for industrial production.
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Paragraph 0032; 0035; 0036; 0041; 0046; 0051; 0056; 0061
(2018/12/13)
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- Acylated glycosidic acid methyl esters generated from the convolvulin fraction of Rhizoma Jalapae Braziliensis by treatment with indium(III) chloride in methanol
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Four hexaglycosides of methyl 3S,12S-dihydroxyhexadecanoate (1-4) were provided after treatment of the crude convolvulin fraction from Rhizoma Jalapae Braziliensis (the root of Ipomoea operculata (GOMES) MART., Convolvulaceae) with indium(III) chloride in
- Ono, Masateru,Oda, Satoko,Yasuda, Shin,Mineno, Tomoko,Okawa, Masafumi,Kinjo, Junei,Miyashita, Hiroyuki,Yoshimitsu, Hitoshi,Nohara, Toshihiro,Miyahara, Kazumoto
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p. 107 - 111
(2017/01/06)
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- 2-alkyl substituted crotonic acid and ester synthesis method thereof
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The invention provides a 2-alkyl substituted crotonic acid and an ester synthesis method thereof.The ester synthesis methodincludes the following steps that 2-alkyl butyric acid, a first catalyst and halogen are used as raw materials to synthesize 2-halogeneated-alkyln-butyric acid; the 2-halogeneated-alkyln-butyric acid, a solvent and inorganic base are used as raw materials to synthesize 2-alkyl crotonic acid; the 2-alkyl crotonic acid, a second catalyst and alcohol are used as raw materials to synthesize 2-alkyl crotonic acid ester. The 2-alkyl substituted crotonic acid and the ester synthesis method have the advantages that the solvents used in all reaction steps are recyclable, a water phase is recycled after finished product filtering, no wastewater is discharged, and a byproduct haloid acid (particularly referring to hydrobromic acid and hydrochloric acid) is obtained after halogen hydridetail gas is absorbed.
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- Resin Glycosides from Ipomoea alba Seeds as Potential Chemosensitizers in Breast Carcinoma Cells
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Multidrug resistance is the expression of one or more efflux pumps, such as P-glycoprotein, and is a major obstacle in cancer therapy. The use of new potent and noncytotoxic efflux pump modulators, coadministered with antineoplastic agents, is an alternative approach for increasing the success rate of therapy regimes with different drug combinations. This report describes the isolation and structure elucidation of six new resin glycosides from moon vine seeds (Ipomoea alba) as potential mammalian multidrug-resistance-modifying agents. Albinosides IV-IX (1-6), along with the known albinosides I-III (7-9), were purified from the CHCl3-soluble extract. Degradative chemical reactions in combination with NMR spectroscopy and mass spectrometry were used for their structural elucidation. Four new glycosidic acids, albinosinic acids D-G (10-13), were released by saponification of natural products 3-6. They were characterized as tetrasaccharides of either convolvulinolic (11S-hydroxytetradecanoic) or jalapinolic (11S-hydroxyhexadecanoic) acids. The potentiation of vinblastine susceptibility in multidrug-resistant human breast carcinoma cells of albinosides 1-6 was evaluated by modulation assays. The noncytotoxic albinosides VII (4) and VIII (5), at a concentration of 25 μg/mL, exerted the strongest potentiation of vinblastine susceptibility, with a reversal factor (RFMCF-7/Vin+) of 201- and >2517-fold, respectively.
- Cruz-Morales, Sara,Casta?eda-Gómez, Jhon,Rosas-Ramírez, Daniel,Fragoso-Serrano, Mabel,Figueroa-González, Gabriela,Lorence, Argelia,Pereda-Miranda, Rogelio
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p. 3093 - 3104
(2017/01/03)
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- Three acylated glycosidic acid methyl esters and two acylated methyl glycosides generated from the convolvulin fraction of seeds of Quamoclit pennata by treatment with indium(III) chloride in methanol
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Treatment of the ether-insoluble resin glycoside (convolvulin) fraction from seedsof Quamoclit pennata (Convolvulaceae) with indium(III) chloride in methanol provided three oligoglycosides of hydroxy fatty acid (glycosidic acid) methyl esters and two methyl glycosides, which were partially acylated by a glycosidic acid, 75-hydroxydecanoic acid 7-0-β-d-quinovopyranoside (quamoclinic acid B) and/or two organic acids, (E)-2-methylbut-2-enoic (tiglic) acid and/or 3R-hydroxy-2R-methylbutyric (nilic) acid. Theirstructures were elucidated on the basis of spectroscopic data and chemical conversions.
- Akiyama, Kousuke,Mineno, Tomoko,Okawa, Masafumi,Kinjo, Junei,Miyashita, Hiroyuki,Yoshimitsu, Hitoshi,Nohara, Toshihiro,Ono, Masateru
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p. 952 - 961
(2013/10/21)
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- Mammalian multidrug resistance lipopentasaccharide inhibitors from Ipomoea alba seeds
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As part of an ongoing project to identify inhibitors of multidrug efflux pumps, three new resin glycosides, albinosides I-III (1-3), were isolated from a CHCl3-soluble extract from the seeds of moon vine (Ipomoea alba). Their structures were established through NMR spectroscopy and mass spectrometry as partially acylated branched pentasaccharides derived from three new glycosidic acids, named albinosinic acids A-C (4-6). The same oligosaccharide core formed by two d-quinovose, one d-glucose, and two l-rhamnose units was linked to either convolvulinolic or jalapinolic acid for 1 and 3, respectively. They were partially esterified with (2R,3R)-3-hydroxy-2-methylbutanoic, acetic, or 2-methyl-2-butenoic acid. Compound 2 has two d-quinovose and three l-rhamnose units, linked to convolvulinolic acid, and its esterifying residues were characterized as two units of 2-methyl-2-butenoic acid. The aglycone lactonization site was located at C-2 of the terminal rhamnose unit (Rha) for 1, at C-3 of the terminal rhamnose unit (Rha') for 2, and at C-3 of the second saccharide unit (Glc) for 3. Reversal of multidrug resistance by this class of plant metabolites was also evaluated in vinblastine-resistant human breast carcinoma cells (MCF-7/Vin). The noncytotoxic compound 3 exerted the strongest potentiation effect of vinblastine susceptibility to over 2140-fold, while a moderate activity was observed for 1 (3.1-fold) and 2 (2.6-fold) at a concentration of 25 μg/mL.
- Cruz-Morales, Sara,Castaneda-Gomez, Jhon,Figueroa-Gonzalez, Gabriela,Mendoza-Garcia, Alma Delia,Pereda-Miranda, Rogelio,Lorence, Argelia
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p. 1603 - 1611,9
(2020/09/09)
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- Resin glycosides from the aerial parts of Operculina turpethum
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Three glycosidic acids, turpethic acids A-C, and two intact resin glycosides, turpethosides A and B, all having a common pentasaccharide moiety and 12-hydroxy fatty acid aglycones of different chain lengths, were obtained from the aerial parts of Operculina turpethum. Their structures were elucidated by spectroscopic analyses and chemical correlations. The aglycones were characterized as 12-hydroxypentadecanoic acid in two compounds, 12-hydroxyhexadecanoic acid in two other components, and 12-hydroxyheptadecanoic acid in the fifth compound, which were all confirmed by synthesis. The absolute configurations of these aglycones were all established as S by Mosher's method. These compounds represent the first examples of resin glycosides with a monohydroxylated 12-hydroxy fatty acid as an aglycone, and one compound is the first described resin glycoside having a hydroxylated C17 fatty acid as its aglycone.
- Ding, Wenbing,Jiang, Zi-Hua,Wu, Ping,Xu, Liangxiong,Wei, Xiaoyi
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experimental part
p. 165 - 174
(2012/10/08)
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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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- Medicinal flowers. XXXIII.1 anti-hyperlipidemic and anti-hyperglycemic effects of chakasaponins I-III and structure of chakasaponin IV from flower buds of Chinese tea plant (Camellia sinensis)
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Effects of principal saponins, chakasaponins I-III, from the flower buds of Camellia sinensis cultivated in Fujian province, China on plasma triglyceride (TG) and glucose levels in olive oil or sucrose-loaded mice were examined. Chakasaponins I-III at 50 and 100 mg/kg significantly inhibited increases in plasma TG and glucose levels. Furthermore, they prevented gastric emptying, suggesting that the former inhibitory effect is partly dependent on the inhibition of gastric emptying. In addition, the chemical structure of a new acylated oleanane-type triterpene oligoglycoside, chakasaponin IV, was elucidated on the basis of chemical and physicochemical evidence.
- Matsuda, Hisashi,Hamao, Makoto,Nakamura, Seikou,Kon'i, Haruka,Murata, Megumi,Yoshikawa, Masayuki
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experimental part
p. 674 - 680
(2012/07/13)
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- Calysolins I-IV, resin glycosides from calystegia soldanella
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Four new resin glycosides having intramolecular cyclic ester structures (jalapins), named calysolins I-IV (1-4), were isolated from the methanol extract of leaves, stems, and roots of Calystegia soldanella, along with one known jalapin (5) derivative. The structures of 1-4 were determined on the basis of spectroscopic data and chemical evidence. They fall into two types, one having a 22-membered ring (1 and 4) and the other with a 27-membered ring (2 and 3). The sugar moieties of 1-4 were partially acylated by some organic acids. Compound 4 is the first example of a hexaglycoside of jalapin.
- Takigawa, Ayako,Muto, Haruka,Kabata, Kiyotaka,Okawa, Masafumi,Kinjo, Junei,Yoshimitsu, Hitoshi,Nohara, Toshihiro,Ono, Masateru
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experimental part
p. 2414 - 2419
(2012/01/15)
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- Palladium(II)-catalyzed selective oxidation of α,β-unsaturated aldehydes to α,β-unsaturated carboxylic acids with hydrogen peroxide
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Palladium(II)-catalyzed chemoselective oxidation of αβ- unsaturated aldehydes with hydrogen peroxide to give Oα,β-unsaturated carboxylic acids was performed. Cinnamaldehyde was effectively catalyzed by palladium(II) trifluoroacetate to generate cinnamic acid in 92% yield under organic solvent-free conditions. The reaction appears to be applicable to various α,β-unsaturated aldehydes. Copyright
- Kon, Yoshihiro,Imao, Daisuke,Nakashima, Takuya,Sato, Kazuhiko
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supporting information; experimental part
p. 430 - 431
(2010/03/04)
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- Medicinal flowers. XXVI.1 structures of acylated oleanane-type triterpene oligoglycosides, yuchasaponins A, B, C, and D, from the flower buds of camellia oleifera-gastroprotective, aldose reductase inhibitory, and radical scavenging effects
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The methanolic extract and its 1-butanol-soluble fraction from the flower buds of Camellia oleifera Abel were found to exhibit inhibitory effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats. The ethyl acetate- and 1-butanol-solubl
- Sugimoto, Sachiko,Chi, Guihua,Kato, Yasuyo,Nakamura, Seikou,Matsuda, Hisashi,Yoshikawa, Masayuki
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experimental part
p. 269 - 275
(2009/11/30)
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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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- Regioselective biocatalytic hydrolysis of (E,Z)-2-methyl-2-butenenitrile for production of (E)-2-methyl-2-butenoic acid
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Acidovorax facilis 72W nitrilase catalyzed the regioselective hydrolysis of (E,Z)-2-methyl-2-butenenitrile, producing only (E)-2-methyl-2-butenoic acid with no detectable conversion of (Z)-2-methyl-2-butenenitrile. (E)-2-Methyl-2-butenoic acid, produced in aqueous solution as the ammonium salt, was readily separated from (Z)-2-methyl-2-butenenitrile, and isolated in high yield and purity. The combination of nitrile hydratase and amidase activities of several Comamonas testosteroni strains were also highly regioselective for the production of (E)-2-methyl-2-butenoic acid from (E,Z)-2-methyl-2- butenenitrile.
- Hann, Eugenia C.,Sigmund, Amy E.,Fager, Susan K.,Cooling, Frederick B.,Gavagan, John E.,Bramucci, Michael G.,Chauhan, Sarita,Payne, Mark S.,DiCosimo, Robert
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p. 577 - 581
(2007/10/03)
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- Pyrrolidine modulators of CCR5 chemokine receptor activity
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Pyrrolidine compounds of Formula I: (wherein 1, R2, R3, R4, R5,R6a, R6b, R7 and R8 are defined herein) are described. The compounds are modulators of CCR5 chemokine receptor activity. The compounds are useful, for example, in the prevention or treatment of infection by HIV and the treatment of AIDS, as compounds or pharmaceutically acceptable salts, or as ingredients in pharmaceutical compositions, optionally in combination with other antivirals, immunomodulators, antibiotics or vaccines. Methods of treating AIDS and methods of preventing or treating infection by HIV are also described.
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- Action of L-aminoacylase and L-amino acid oxidase on 2-amino-3- methylpent-4-enoic acid [Δ(4)-dehydroisoleucine and alloisoleucine] stereoisomers: An alternative route to a stereochemically pure compound and the application to the synthesis of (R)-2-methylbutan-1-ol
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The action of L-aminoacylase and L-amino acid oxidase on the stereoisomers of 2-amino-3-methylpent-4-enoic acid was examined, to secure stereochemically pure compounds related to L-alloisoleucine. A scalemic mixture [(2S,3R)- (90.0%), (2S,3S)(3.2%), (2R,3S)- (5.9%), (2R,3R)- (0.9%)] of the N-trifluoroacetyl derivatives of the title compound, which was prepared by an asymmetric Claisen rearrangement, was submitted to Aspergillus L-aminoacylase-catalyzed hydrolysis. Only the (2S,3R)- and (2S,3S)isomers were hydrolyzed to give the corresponding amino acids. The subsequent treatment of these isomers with Crotalus adamanteus L-amino acid oxidase afforded the pure (2S,3R)-isomer, related to L-alloisoleucine, in more than 99% stereochemically pure form. Moreover, the product was converted to L- alloisoleucine and (R)-2-methylbutan-1-ol via a chemoenzymatic procedure.
- Bakke, Mikio,Ohta, Hiromichi,Kazmaier, Uli,Sugai, Takeshi
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p. 1671 - 1677
(2007/10/03)
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- The Gas-Phase Elimination Kinetics of 2-Hydroxy-2-Methylbutyric Acid and 2-Ethyl-2-Hydroxybutyric Acid
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The elimination kinetics of the title compounds have been examined over the temperature range of 270 - 320 deg C and pressure range of 19 - 117 torr.The reactions, carried out in seasoned vessels, with the free-radical suppressor toluene always present, are homogeneous, unimolecular, and follow a first-order rate law.The products of 2-hydroxy-2-methylbutyric acid are 2-butanone, CO, and H2O; while of 2-ethyl-2-hydroxybutyric acid are 3-pentanone, CO, and H2O.The rate coeffcient is expressed by the following Arrhenius equation: for 2-hydroxy-2-methylbutyric acid, log k1(s-1) = (12.87 +/- 0.19) - (171.2 +/- 2.1) kJ mol-1 (2.303 RT)-1; and for 2-ethyl-2-hydroxybutyric acid, log k1(s-1) = (12.13 +/- 0.34) - (159.4 +/- 3.7) kJ mol-1 (2.303 RT)-1.Augmentation of alkyl bulkiness at the 2-position of the 2-hydroxycarboxylic acids showed an increase in the rate of dehydration.The electron release of alkyl groups, rather than steric acceleration, appears to enhance the pyrolysis decomposition of these substrates.These reactions are believed to proceed through a semi-polar five-membered cyclic transition type of mechanism.
- Chuchani, Gabriel,Martin, Ignacio,Rotinov, Alexandra
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p. 849 - 854
(2007/10/02)
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- Carbonylation of Vinyl Halides with Carbonylcobalt
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The reactions of both (E)-β-bromostyrene (E)-(1a) and its Z-isomer (Z)-(1a) with octacarbonyldicobalt in the presence of methyl iodide and calcium hydroxide at 20 deg C in dioxane-water under carbon monoxide (1 atm) gave (E)-cinnamic acid (E)-(2a) exclusively.In contrast, with (E)-1-bromo-2-phenylpropene (E)-(1b), the thermodynamically less stable (Z)-3-phenylbut-2-enoic acid (Z)-(2b) was obtained as the major product together with the (E)-isomer (E)-(2b).The carbonylation of 3-chloroprop-2-enols (7a-f) gave the corresponding furan-2(5H)-ones (8a-f) in good yield.
- Miura, Masahiro,Okuro, Kazumi,Hattori, Ayako,Nomura, Masakatsu
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- STEREOSPECIFIC NICKEL AND PHASE TRANSFER CATALYZED CARBONYLATION OF VINYL BROMIDES AND CHLORIDES
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Nickel cyanide catalyzes the carbonylation of vinyl bromides and chlorides to α,β-unsaturated acids.
- Alper, Howard,Amer, Ibrahim,Vasapollo, Giuseppe
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p. 2615 - 2616
(2007/10/02)
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- The Chemical Constituents of Ajuga Plants. I. neo-Clerodanes from the Leaves of Ajuga nipponensis Makino
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Three new bitter principles, ajugamarin, dihydroajugamarin, and ajugamarin chlorohydrin, which belong to the neo-clerodane group of diterpenoids, have been isolated from the leaves of Ajuga nipponensis.The structures of these compound were established by the chemical and spectroscopic means.The absolute structure of ajugamarin was determined by the X-ray analysis of ajugamarin p-bromobenzoate.Ajugamarin chlorohydrin may have been formed by addition of hydrogen chloride to ajugamarin during the isolation procedure. Keywords ---- Ajuga nipponensis; Labiatae; diterpenoid; neo-clerodane; bitter principle; ajugamarin; dihydroajugamarin; ajugamarin chlorohydrin; X-ray crystallographic analysis
- Shimomura, Hiroko,Sashida, Yutaka,Ogawa, Kazunori,Iitaka, Yoichi
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p. 2192 - 2199
(2007/10/02)
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- COMPONENTS OF THE ROOTS OF Ferula tschatcalensis
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With the aid of column chromatography, the following compounds have been isolated from the roots of Ferula tschatcalensis M.Pimen. and identified: juniferin, ferocinin, xeroferol, and fexerin, and also the new sesquiterpene ester chatferin, C20H32O4, D20 +6.2 deg (1.53; ethanol), nD20 1.5136.On the basis of spectral characteristics and a transition to known substances, it has been established that chatferin has the structure of 2-tigloyl-7,8-epoxyjuniferol.
- Sagitdinova, G. V.,Saidkhodzhaev, A. I.,Malikov, V. M.
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p. 685 - 687
(2007/10/02)
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- HIGH-TEMPERATURE TRANSFORMATIONS OF ALKYL-SUBSTITUTED ACRYLIC ACIDS IN AQUEOUS SOLUTIONS
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Unlike unsubstituted acrylic acid, β-alkyl-substituted acrylic acids and α-ethyl-acrylic acid undergo hydration to a small degree (up to 4percent) when heated (180 - 230 deg C) with water.The main directions in the transformations are rearrangement through migration of the double bond and decarboxylation.During the rearrangement of α-ethylacrylic acid tiglic acid was obtained with a good yield.
- Salov, V. N.,Zil'berman, E. N.,Usova, N. Yu.
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p. 1778 - 1780
(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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- REACTIONS OF AN ALKENYLTITANOCENE
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The alkenyltitanium compound Cp2Ti(trans-C(CH3)=CHCH3) undergoes a reductive coupling reaction with acetone to give an alkoxy complex.With CO2, 2,6-xylylisocyanide, phenylisocyanate, CS2, diphenylacetylene and CO, insertions occur.
- Klei, E.,Teuben, J. H.
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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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