- Steroidal glycosides from Allium cyrillii Bulbs
-
Two spirostanol saponins, one of which was a new compound, were isolated among the steroidal glycosides of Allium cyrillii Ten. Bulbs. The structures of these glycosides were established using chemical and spectral analytical methods as β-D-glycopyranosyl-(1 →2)-[β-D-xylopyranosyl-(1 →3)]-β-D-glucopyranosyl-(1 →4)-β-D-galactopyranosyl- (1→3)-(25R)-5α-spirostan-2α,3β-diol and β-D-glucopyranosyl-(1→2)-[4-O-(3-hydroxy-3-methylglutaryl) -β-D-xylopyranosyl-(1 →3)]-β-D-glucopyranosyl-(1 →4)-β-D-galactopyranosyl-(1→3)-(25R)-5α-spirostan-2α, 3β-diol.
- Tolkacheva,Shashkov,Chirva
-
-
Read Online
- SYNTHESIS OF MEVALONOLACTONE FROM 4-(β-HYDROXYETHYL)-4-METHYL-1,3-DIOXANE
-
A method has been developed for obtaining mevalonolactone and 3-hydroxy-3-methylglutaric acid from an industrial waste, 4-(β-hydroxyethyl)-4-methyl-1,3-dioxane.
- Sargsyan, M. S.,Manukyan, A. T.,Mkrtumyan, S. A.,Gevorkyan, A. A.
-
-
Read Online
- PYRROLIZIDINE ALKALOIDS FROM CROTALARIA LACHNOSEMA AND C. NARAGUTENSIS
-
Crotalaria lachnosema, from Nigeria, was found to contain two pyrrolizidine alkaloids, dicrotaline and its acetyl derivative, the natural occurrence of which is reported for the first time.The major alkaloid in C. naragutensis was nilgirine, together with integerrimine, usaramine and a new alkaloid, acetyl integerrimine.Key Word Index - Crotalaria lachnosema; C. naragutensis; pyrrolizidine alkaloid; dicrotaline; acetyl dicrotaline; integerrimine; acetyl integerrimine; nilgirine; usaramine.
- Mattocks, Robin A.,Nwude, Nwankwo
-
-
Read Online
- FUNGAL METABOLITES XIII : NEW CYTOTOXIC TRITERPENE FROM HEBELOMA SPECIES (BASIDIOMYCETES)
-
A new cytotoxic lanostane triterpene, named 3-β-acetyl-2-α-(3'-hydroxy-3'-methyl)glutarylcrustulinol, was isolated from Hebeloma crustuliniforme and H. sinapizans.The structure has been elucidated by chemical correlations and spectroscopic evidences.
- Bernardi, M. De,Fronza, G.,Gianotti, M. P.,Mellerio, G.,Vidari, G.,Vita-Finzi, P.
-
-
Read Online
- Control of β-Branching in Kalimantacin Biosynthesis: Application of 13C NMR to Polyketide Programming
-
The presence of β-branches in the structure of polyketides that possess potent biological activity underpins the widespread importance of this structural feature. Kalimantacin is a polyketide antibiotic with selective activity against staphylococci, and its biosynthesis involves the unprecedented incorporation of three different and sequential β-branching modifications. We use purified single and multi-domain enzyme components of the kalimantacin biosynthetic machinery to address in vitro how the pattern of β-branching in kalimantacin is controlled. Robust discrimination of enzyme products required the development of a generalisable assay that takes advantage of 13C NMR of a single 13C label incorporated into key biosynthetic mimics combined with favourable dynamic properties of an acyl carrier protein. We report a previously unassigned modular enoyl-CoA hydratase (mECH) domain and the assembly of enzyme constructs and cascades that are able to generate each specific β-branch.
- Walker, Paul D.,Williams, Christopher,Weir, Angus N. M.,Wang, Luoyi,Crosby, John,Race, Paul R.,Simpson, Thomas J.,Willis, Christine L.,Crump, Matthew P.
-
supporting information
p. 12446 - 12450
(2019/08/16)
-
- POLYMERS PREPARED FROM MEVALONOLACTONE AND DERIVATIVES
-
Described herein polymer precursor compounds (aka polymer building blocks) of derived from biobased compounds, and specifically biobased mevalonolactone and its related derivatives. Through oxidation these biobased precursors can be reacted to yield building blocks for (unsaturated-) polyesters, polyester polyols and polyamides, as well as precursors for glycidyl esters and omega-alkenyl esters. Through reduction, these biobased precursors can be reacted to yield building blocks for (unsaturated-) polyesters, polyester polyols, polycarbonates, as well as precursors for glycidyl ethers and omega-alkenyl ethers. Through nucleophilic ring opening and/or amidation, these biobased precursors can be reacted to yield building blocks for polyester polyols, chain-extender for polyurethanes, or polyester-amides.
- -
-
-
- POLYMERS PREPARED FROM MEVALONOLACTONE AND DERIVATIVES
-
Described herein polymer precursor compounds (aka polymer building blocks) of derived from biobased compounds, and specifically biobased mevalonolactone and its related derivatives. Through oxidation these biobased precursors can be reacted to yield building blocks for (unsaturated-) polyesters, polyester polyols and polyamides, as well as precursors for glycidyl esters and omega-alkenyl esters. Through reduction, these biobased precursors can be reacted to yield building blocks for (unsaturated-) polyesters, polyester polyols, polycarbonates, as well as precursors for glycidyl ethers and omega-alkenyl ethers. Through nucleophilic ring opening and/or amidation, these biobased precursors can be reacted to yield building blocks for polyester polyols, chain-extender for polyurethanes, or polyester-amides.
- -
-
Page/Page column 53
(2016/06/06)
-
- NATURAL MOLECULES EXTRACTED FROM BERGAMOT TISSUES, EXTRACTION PROCESS AND PHARMACEUTICAL USE
-
A natural molecule extracted from a citrus fruit characterized by the fact that its structure is a flavonoid linked to 3-hydroxy-3-methyl glutaric acid and an extraction process in which: the extraction of chopped fruit is conducted in pure or mixed chloroform, ethanol or methanol for a certain time, the filtrate is evaporated to dryness, the residue is submitted to solid phase extraction in order to separate the flavonoidic portion from the other class of compounds, the flavonoid mixture is separated through a preparative HPLC chromatographic system. Pharmaceutical use of the natural molecule extracted from a citrus fruit used as anticholesterol drug.
- -
-
Page/Page column 5
(2010/04/28)
-
- An unusual acylated malvidin 3-glucoside from flowers of Impatiens textori Miq. (Balsaminaceae)
-
Acylated malvidin 3-glucoside was isolated from the purple flowers of Impatiens textori Miq. as a major anthocyanin component along with malvidin 3-(6″-malonyl-glucoside). Its structure was elucidated to be malvidin 3-O-[6-O-(3-hydroxy-3-methylglutaryl)-β
- Tatsuzawa, Fumi,Saito, Norio,Mikanagi, Yuki,Shinoda, Koichi,Toki, Kenjiro,Shigihara, Atsushi,Honda, Toshio
-
experimental part
p. 672 - 674
(2010/01/16)
-
- Statin-like principles of bergamot fruit (Citrus bergamia): Isolation of 3-hydroxymethylglutaryl flavonoid glycosides
-
The 3-hydroxy-3-methylglutaryl neohesperidosides of hesperetin (brutieridin, 1) and naringenin (melitidin, 2) were isolated and detected from the fruits of bergamot (Citrus bergamia). The structures of these compounds were determined by spectroscopic and
- Di Donna, Leonardo,De Luca, Giuseppina,Mazzotti, Fabio,Napoli, Anna,Salerno, Raffaele,Taverna, Domenico,Sindona, Giovanni
-
supporting information; experimental part
p. 1352 - 1354
(2009/12/29)
-
- Medicinal foodstuffs. XIII.1 saponin constituents with adjuvant activity from hyacinth bean, the seeds of Dolichos lablab L. (2) : Structures of lablabosides D, E, and F
-
Following the characterization of lablabosides A, B, and C, new oleanane-type triterpene bisdesmosides, lablabosides D, E, and F, were isolated from the glycosidic fraction with adjuvant activity obtained from the seeds of Dolichos lablab L. (Leguminosae). Their chemical structures were elucidated on the basis of chemical and physicochemical evidence as follows : 3-O-[α-L-rhamnopyranosyl (1→2)-β-D-galactopyranosyl (1→2)-β-D-glucopyranosiduronic acid]-28-O-[6-O-(3-hydroxy-3-methylglutaroyl)-β-D-glucopyranosyl] 24-epi-hederagenin (lablaboside D), 3-O-[α-L-rhamnopyranosyl (1→2)-β-D-galactopyranosyl (1→2)-β-D-glucopyranosiduronic acid]-28-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl] 24-epi-hederagenin (lablaboside E), 3-O-[α-L-rhamnopyranosyl (1→2)-β-D-galactopyranosyl (1→2)-β-D-glucopyranosiduronic acid]-28-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→2)-β-D-glucopyranosyl] oleanolic acid (lablaboside F).
- Komatsu, Hajime,Murakami, Toshiyuki,Matsuda, Hisashi,Yoshikawa, Masayuki
-
p. 703 - 710
(2007/10/03)
-
- STEROIDAL SAPONINS FROM THE BULBS OF LILIUM BROWNII
-
The methanol extract of the fresh bulbs of Lilium brownii has yielded a 27-acyloxyspirostanol saponin, named brownioside and a furospirostanol saponin, which appear to be new constituents.The respective structures have been shown by the spectroscopic evidence and alkaline- and acid-catalysed degradations to be (25R)-27-O-(3-hydroxy-3-methylglutaroyl)-spirost-5-en-3β,27-diol 3-O-2)>-β-D-glucopyranoside and (22S,25S)-26-O-β-D-glucopyranosyl-22,25-epoxyfurost-5-en-3β,26-diol 3-O2)>-β-D-glucopyranoside.Several known phenolic compounds have also been isolated and identified.
- Mimaki, Yoshihiro,Sashida, Yutaka
-
p. 2267 - 2271
(2007/10/02)
-
- Process for preparation of 3-hydroxy-3-methyl-glutaric acid
-
For the preparation of 3-hydroxy-3-methyl-glutaric acid a process is disclosed based on the direct oxidation with nitric acid of 3-methyl-1,3,5-pentanetriol.
- -
-
-
- Studies on the constituents of Actinostemma lobatum MAXIM. IV. Structures of Lobatosides C, D and H, the dicrotalic acid esters of bayogenin bisdesmosides isolated from the herb.
-
Eight bayogenin glycosides, lobatosides A-H, were isolated from the herb of Actinostemma lobatum MAXIM.(Curcurbitaceae).The isolation of lobatosides A-H and the structures of lobatosides A, C, D and H are described.Lobatoside A is 3-O-2)-β-D-glucopyranosyl>bayogenin (2β,3β,23-trihydroxyolean-12-en-28-oic acid).Lobatosides C, D and H are dicrotalic acid (3-hydroxy-3-methylglutaric acid) esters of the 28-2)-α-L-arabinopyranosyl>ester, 28-3)-αL-rhamnopyranosyl-(1->2)-α-L-arabinopyranosyl>ester and 28-3)-α-L-rhamnopyranosyl-(1->2)-α-L-arabinopyranosyl>ester of lobatoside A, respectively.Dicrotalic acid is linked at one end to the C4hydroxyl group of the α-L-arabinopyranosyl group in the C3-linked sugar moiety, and at the order end to the C4-hydroxyl group of the α-L-rhamnopyranosyl group in the ester-linked sugar moiety to form a macrocyclic structure ("cyclic bisdesmoside").Lobatoside H was proved to be identical with tubeimoside I isolated from the tuber of Bolbostemma paniculatum (MAXIM).FRANQUET(Cucurbitaceae).Keywords - Actinostemma lobatum; Cucurbitaceae; oleanane-type triterpene glycoside; bayogenin; 2β,3β,23-trihydroxyolean-12-en-28-oic acid; lobatoside;,tubeimoside I; cyclic bisdesmoside; dicrotalic acid; 3-hydroxy-3-methylglutaric acid.
- Fujioka, Toshihiro,Masayo, Iwamoto,Iwase, Yukiko,Hachiyama, Shizuko,Okabe, Hikaru,et. al
-
p. 1770 - 1775
(2007/10/02)
-
- Studies on the constituents of Actinostemma lobatum MAXIM. V. Structures of Lobatosides B,E,F and G, the dicrotalic acid esters of bayogenin bisdesmosides isolated from the herb
-
The structures of lobatosides B, E, F and G, the dicrotalic acid esters of bayogenin bisdesmosides isolated from the herb of Actinostemma lobatum MAXIM. (Cucurbitaceae), were determined on the basis of chemical and spectral evidence.Lobatoside B is the dicrotalic acid (3-hydroxy-3-methylglutaric acid ) ester of 3-O-2)-β-D-glucopyranosyl>bayogenin 28-2)-α-L-arabinopyranosyl> ester.Dicrotalic acid is linked at one end to the C6-hydroxyl group of the terminal β-D-glucopyranosyl group in the C3-linked sugar moiety, and at the other end to the C4-hydroxyl group of the α-L-rhamnopyranosyl group in the ester-linked sugar moiety to form a macrocyclic structure (cyclic bisdesmoside).Lobatosides E, F and G are cyclic bisdesmosides of bayogenin similar to lobatoside B, but different in the numbers and species of the component sugars and positions of the ester linkages of the dicrotalic acid.Keywords - Actinostemma lobatum; Cucurbitaceae; lobatoside; bayogenin glycoside; cyclic bisdesmoside; dicrotalic acid; NOE difference spectrum; decoupling difference spectrum.
- Fujioka, Toshihiro,Iwamoto, Masayo,Iwase, Yukiko,Hachiyama, Shizuko,Okabe, Hikaru,et al.
-
p. 2355 - 2360
(2007/10/02)
-
- SYNTHESIS OF SUBSTITUTED BENZENOIDS AND BIPHENYLS VIA DIELS-ALDER CYCLOADDITION OF 6-METHOXY-2-PYRONES
-
A convenient synthesis of substituted 6-methoxy-2-pyrones from alkyl and aryl esters is described.These pyrones undergo Diels-Alder reactions with acetylenic dienophiles to provide an efficient route to polysubstituted benzoates, phthalates and biphenyls.
- Ahmed, Salman A.,Bardshiri, Esfandiar,Simpson, Thomas J.
-
p. 1595 - 1596
(2007/10/02)
-
- SYNTHETIC STUDIES ON NOGALAMYCIN CONGENERS ; TOTAL SYNTHESES OF (+)-NOGARENE, (+)-7-DEOXYNOGAROL, AND (+)-7-CON-O-METHYLNOGAROL
-
According to the retrosynthetic perspective, the title total syntheses were accomplished by employing the regioselective Diels-Alder reactions of the (+)-naphthoquinone (5), the CDEF-ring system of nogalamycin congeners, with various structural types of dienes (8, 16, and 26).The highly functionalized dienes (16 and 26) incorporating all the functionalities present in the A-rings of (+)-7-deoxynogarol (3) and (+)-7-con-O-methylnogarol (2), were prepared efficiently by way of the 1,4-cyclohexadiene and 2-cyclohexanone derivatives (6 and 21), respectively.Reaction mechanism of the key Diels-Alder reaction was also discussed in terms of its stereoselectivity.
- Kawasaki, Motoji,Matsuda, Fuyuhiko,Terashima, Shiro
-
p. 5727 - 5744
(2007/10/02)
-
- TANGSHENOSIDES I AND II FROM CHUAN-DANGSHEN, THE ROOT OF CODONOPSIS TANGSHEN OLIV.
-
From the roots of Codonopsis tangshen (Chuan-dangshen) cultivated in Sichuan, China, two new phenylpropanoid glucosides named tangshenosides I and II were isolated together with syringin. the structures of both compounds including the absolute configurations were elucidated by physical and chemical procedures.KEYWORDS - codonopsis tangshen; Dangshen; Campanulaceae; Chinese folk medicine; tangshenoside I; tangshenoside II; syringin; phenylpropanoid glycoside;
- Mizutani, Kenji,Yuda, Masamichi,Tanaka, Osamu,Saruwatari, Yuh-ichiro,Jia, Ming-Ru,et al.
-
p. 2726 - 2729
(2007/10/02)
-
- OXIDATION OF 4-METHYLENETETRAHYDROPYRAN AND 4-METHYL-5,6-DIHYDRO-2H-PYRAN WITH NITRIC ACID. SYNTHESIS OF CITRIC AND OXALIC ACIDS
-
The oxidation of 4-methylenetetrahydropyran and 4-methyl-5,6-dihydro-2H-pyran with nitric acid was studied.In the presence of an equimolar amount of nitrogen oxide (N2O3 or N2O4) the products from the oxidation of 4-methylenetetrahydropyran are citric and oxalic acids.Under analogous conditions 4-methyl-5,6-dihydro-2H-pyran is oxidized to oxalic acid.During the oxidation of 4-methylenetetrahydropyran and 4-methyl-5,6-dihydro-2H-pyran without the previous addition of nitrogen oxides 3-hydroxy-3-methylglutaric acid is also obtained.
- Sargsyan, M. S.,Mkrtumyan, S. A.,Gevorkyan, A. A.
-
p. 1963 - 1967
(2007/10/02)
-
- A Convenient Synthesis of Isotopically Labelled Anthraquinones, Chrysophanol, Islandicin, and Emodin. Incorporation of Chrysophanol into Tajixanthone in Aspergillus variecolor
-
Cycloaddition reactions of labelled 6-methoxy-3-methyl-2-pyrone (1) with naphthoquinones provide the common fungal anthraquinones, chrysophanol (2), islandicin (3), and emodin (4) suitably labelled for biosynthetic studies, as demonstrated by synthesis and incorporation of chrysophanol into the xanthone metabolite, tajixanthone (17) in Aspergillus variecolor.
- Ahmed, Salman A.,Bardshiri, Esfandiar,Simpson, Thomas J.
-
p. 883 - 884
(2007/10/02)
-
- 3-Alkyl-3-hydroxyglutaric acids: A new class of hypocholesterolemic HMG CoA reductase inhibitors. 1
-
Derivatives of 3-hydroxy-3-methylglutaric acid (HMG), a portion of the substrate for HMG CoA reductase, were prepared and tested for their inhibitory action against rat liver HMG CoA reductase and for their hypocholesterolemic activity. Structure-dependent competitive inhibition was observed. Optimal structures had a freee dicarboxylic acid with an alkyl group of 13-16 carbons at position 3. 3-n-Pentadecyl-3-hydroxyglutaric acid (IC50 = 50 μM) reduced serum cholesterol in the Triton-treated rat and HMG CoA reductase activity in the 20,25-diazacholesterol-treated rat.
- Baran,Laos,Langford,Miller,Jett,Taite,Rohrbacher
-
p. 597 - 601
(2007/10/02)
-
- Process for the preparation of 3-methyl-3-hydroxy-glutaric acid
-
A novel process for the preparation of 3-methyl-3-hydroxy-glutaric acid of the formula STR1 comprising reacting a compound of the formula STR2 wherein R is selected from the group consisting of alkoxy of 1 to 6 carbon atoms, formyloxy, halogen and acyloxy of 2 to 18 carbon atoms with at least two equivalents of a compound of the formula wherein X is an alkali metal and R1 is alkyl of 1 to 6 carbon atoms to obtain a compound of the formula STR3 and subjecting the latter to saponification or optionally catalytic thermal decomposition to obtain 3-methyl-3-hydroxy-glutaric acid and a novel intermediate.
- -
-
-
- Studies on a Synthesis of (RS)-Mevalonic Acid Lactone
-
Full details of a high yielding synthesis of mevalonic acid lactone (1) which is of particular value in the preparation of 3- and/or 3'-labelled compounds are described.The key step, conversion of 3-hydroxy-3-methylpentane-1,5-dioic acid (3) into 3-hydroxy-3-methylpentane-1,5-dioic anhydride (4) using acetic anhydride, has been fully investigated, and an additional method using acetyl chloride and triethylamine is described.
- Bardshiri, Esfandiar,Simpson, Thomas J.,Scott, A. Ian,Shishido, Kozo
-
p. 1765 - 1767
(2007/10/02)
-
- Reinvestigation of a Synthesis of (R,S)-Mevalonolactone
-
An n.m.r. study of the reaction of 3-hydroxy-3-methylpentane-1,5-dioic acid (5) with excess of acetic anhydride is described.It has shown that 3-hydroxy-3-methylpentane-1,5-dioic acid anhydride (2), previously described by Scott and Shishido as an intermediate in their synthesis of mevalonolactone, is formed only transiently, along with 3-acetoxy-3-methylpentane-1,5-dioic acid (6).Both intermediates eventually give 3-acetoxy-3-methylpentane-1,5-dioic acid anhydride (3).To obtain (R,S)-mevalonolactone, sodium borohydride reduction of 3-hydroxy-3-methylpentane-1,5-dioic acid anhydride (2), prepared from the diacid (5) and N,N-dicyclohexylcarbodi-imide, is shown to be better than reduction of 3-acetoxy-3-methylpentane-1,5-dioic acid anhydride (3).
- Lewer, Paul,MacMillan, Jake
-
p. 1417 - 1420
(2007/10/02)
-
- Macrocyclic Pyrrolizidine Alkaloids. Synthesis and Stereochemistry of (+)-Dicrotaline (13β-Hydroxy-13α-methyl-1,2-didehydrocrotalanine) and (+)-13-epi-Dicrotaline
-
Treatment of (+)-retronecine (1) with the trimethylsilyl ether of 3-hydroxy-3-methylglutaric anhydride gave a mixture of the 7- and 9-monoesters of (+)-retronecine (1).Lactonisation of this mixture was achieved using the corresponding pyridine-2-thiol esters to give (+)-dicrotaline (13β-hydroxy-13α-methyl-1,2-didehydrocrotalanine) (2) and (+)-13-epi-dicrotaline (3).The absolute configuration at C-13 in both compounds was established by a sequence of selective reactions on each epimer to yield optically active mevalonolactone.
- Brown, Kenneth,Devlin, J. Alastair,Robins, David J.
-
p. 1819 - 1824
(2007/10/02)
-
- STEROID SAPONINS AND SAPOGENINS OF Allium. THE STRUCTURE OF KARATAVIOSIDE B
-
A new glycoside of the spirostan series - karatavioside B (I) - has been isolated from an ethanolic extract of the inflorescences of Allium karataviense Rgl. (family Liliaceae).On the basis of chemical transformations and spectral characteristics the structure of (I) has been established as 25(R)-spirost-5-ene-2α,3β-diol S-O--(1-3)>--O-β-D-glucopyranosyl-(1-4)-β-D-galactopyranoside>.
- Bollerner, Yu. S.,Abdullaev, N. D.,Gorovits, M. B.,Abubakirov, N. K.
-
p. 186 - 190
(2007/10/02)
-
- An Easy Synthesis of (RS)-Mevalonic Acid Lactone
-
A high-yielding synthesis of mevalonic acid lactone is described which is of particular value in the preparation of 3' labelled compounds.
- Scott, A. Ian,Shishido, Kozo
-
p. 400 - 401
(2007/10/02)
-
