Metabolites of the fungus Arthropsistruncata

1992 ◽  
Vol 70 (5) ◽  
pp. 1338-1347 ◽  
Author(s):  
William A. Ayer ◽  
Peter A. Craw ◽  
John Neary
Keyword(s):  
Spectroscopic Methods ◽  
Liquid Cultures ◽  
X Ray ◽  
Crystallographic Study ◽  
The Absolute ◽  
Absolute Stereochemistry

The structures of 12 new polyketide metabolites produced in liquid cultures of the fungus Arthropsistruncata have been determined by a combination of chemical and spectroscopic methods. Four of these metabolites possess an unusual 2-oxaspiro[4.5]decane skeleton, and the structure assigned to one of these metabolites 20 has been confirmed by an X-ray crystallographic study of the dibenzoyl derivative 21. The absolute stereochemistry of these compounds has been predicted by application of the Harada–Nakanishi dibenzoate rule to arthropsolide D tribenzoate (32).

Metabolites produced by the scleroderris canker fungus, Gremmeniellaabietina. Part 2. The structure of scleroderolide

1987 ◽  
Vol 65 (4) ◽  
pp. 748-753 ◽  
Author(s):  
William A. Ayer ◽  
Yumiko Hoyano ◽  
M. Soledade Pedras ◽  
Jon Clardy ◽  
Edward Arnold
Keyword(s):  
Absolute Configuration ◽  
Temperature Dependent ◽  
X Ray ◽  
Triclinic System ◽  
R Factor ◽  
Racemic Form ◽  
Crystallographic Study ◽  
Acetyl Group ◽  
The Absolute ◽  
Absolute Stereochemistry

Scleroderolide, a yellow pigment produced by the Scleroderris canker fungus Gremmeniellaabietina (Lagerb.) Morelet, is shown to possess structure 1. The structure was determined by an X-ray crystallographic study of the racemic monoacetate 1a. The crystal of 1a belongs to the triclinic system space group, P1, the R-factor converged to 0.047 for the 1957 observed reflections. Scleroderolide occurs mainly as the levorotatory enantiomer (S configuration at C-2′) although on one occasion it was obtained in partially racemic form. The absolute stereochemistry of the levorotatory form was determined by transformation of (−)-sclerodione (5) of known absolute configuration into (−)-scleroderolide. The absolute configuration of (−)-sclerodione was established by correlation with (−)-sclerodin (3). The diacetyl derivative of scleroderolide (1b) shows interesting temperature dependent nuclear magnetic resonance spectral properties due to restricted rotation of the C-4 O-acetyl group. Oxidation of the red pigment sclerodione (5) with m-chloroperbenzoic acid provides both sclerodin (3) and scleroderolide (1). Scleroderolide (1) is the first natural product to be reported that contains a phenylglyoxylate lactone functionality.

Novel sesquiterpenoids from the fairy ring fungus, Marasmiusoreades

1989 ◽  
Vol 67 (5) ◽  
pp. 773-778 ◽  
Author(s):  
William A. Ayer ◽  
Peter A. Craw ◽  
Thomas J. Stout ◽  
Jon Clardy
Keyword(s):  
Crystal Structure ◽  
Hydroxyl Groups ◽  
Spectroscopic Methods ◽  
Fungal Metabolites ◽  
Liquid Cultures ◽  
X Ray ◽  
Crystallographic Study

The structures of four new drimane-type sesquiterpenes 1–4 produced in liquid cultures of the fairy ring fungus, Marasmiusoreades, have been determined by a combination of chemical and spectroscopic methods. The structure assigned to one of these sesquiterpenes (1) has been confirmed by an X-ray crystallographic study. An unprecedented feature of all four sesquiterpenes is the biosynthetic elaboration of C8–C12 and C15 of the drimane skeleton to a dioxabicyclooctane moiety. In addition, two of the sesquiterpenes possess an uncommon α orientation of the hydroxyl groups at C3. Keywords: sesquiterpenes, fungal metabolites, drimanes, fairy ring mushroom, crystal structure.

Absolute Stereochemistry of (-)-Wieland-Miescher Ketone as Established by the X-ray Crystallographic and CD Exciton Chirality Methods

1992 ◽  
Vol 57 (7) ◽  
pp. 1459-1465 ◽  
Author(s):  
Nobuyuki Harada ◽  
Tatsuo Sugioka ◽  
Hisashi Uda ◽  
Takeo Kuriki
Keyword(s):  
Structure Analysis ◽  
Absolute Configuration ◽  
X Ray ◽  
The Absolute ◽  
Absolute Stereochemistry

The 8aR absolute stereochemistry of Wieland-Miescher ketone (-)-I was established by the X-ray structure analysis of its bis(4-bromobenzoate) derivatives (1R,6R,8aR)-(+)-IV and (1R,6S,8aR)-(-)-V. The absolute configuration of (-)-I was corroborated further by the application of the CD exciton chirality method to bis(4-bromobenzoates) (+)-IV and (-)-V.

THE REACTION OF UNSATURATED CARBOHYDRATES WITH CARBON MONOXIDE AND HYDROGEN: V. ABSOLUTE STEREOCHEMISTRY OF ANHYDRODEOXYHEPTITOLS FROM 3,4,6-TRI-O-ACETYL-D-GLUCAL. STEREOCHEMISTRY OF HYDROFORMYLATION. CONFORMATIONAL ANALYSIS

1965 ◽  
Vol 43 (5) ◽  
pp. 1375-1381 ◽  
Author(s):  
Alex Rosenthal ◽  
Hans J. Koch
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Carbon Monoxide ◽  
Absolute Configuration ◽  
Sodium Iodide ◽  
Crystallographic Analysis ◽  
X Ray ◽  
Dicobalt Octacarbonyl ◽  
The Absolute ◽  
Compound Ii ◽  
Absolute Stereochemistry

3,4,6-Tri-O-acetyl-D-glucal reacted with carbon monoxide and hydrogen in the presence of dicobalt octacarbonyl to yield a mixture of two epimeric anhydrodeoxyheptitols, namely, 4,5,7-tri-O-acetyl-2,6-anhydro-3-deoxy-D-manno-heptitol (I) and 4,5,7-tri-O-acetyl-2,6-anhydro-3-deoxy-D-gluco-heptitol (II). De-O-acetylation of the mixture, followed by chromatographic separation, yielded crystalline 2,6-anhydro-3-deoxy-D-manno-heptitol (III) and 2,6-anhydro-3-deoxy-D-gluco-heptitol (IV). Reaction of the mixture of heptitols (I) and (II) with p-bromobenzenesulfonyl chloride, followed by fractional crystallization of the brosylates, gave pure 4,5,7-tri-O-acetyl-2,6-anhydro-1-O-(p-bromophenylsulfonyl)-3-deoxy-D-gluco-heptitol (VII). The absolute configuration of (VII) has been previously established by X-ray crystallographic analysis. The absolute configuration of (III) was established by correlation with that of (VII). The conversion of compound (II) into various derivatives is described.Reaction of 3,4,6-tri-O-acetyl-D-glucal with carbon monoxide and deuterium afforded 2,6-anhydro-3-deoxy-D-manno-heptitol-1,1,3-2H3 (XIII) and 2,6-anhydro-3-deoxy-D-gluco-heptitol-1,1,3-2H3 (XIV). Examination of the nuclear magnetic resonance (n.m.r.) spectra of the normal and deuterated anhydrodeoxyheptitols confirmed the structural assignments and showed that cis addition to the double bond took place to give (XIV).Comparison of the exchange reaction of sodium iodide with 4,5,7-tri-O-acetyl-2,6-anhydro-3-deoxy-1-O-tosyl-D-gluco-heptitol (VIII) and with 4,5,7-tri-O-acetyl-2,6-anhydro-3-deoxy-1-O-tosyl-D-manno-heptitol (XV) revealed that the equatorial primary tosyloxy group of (VIII) was exchanged by iodine twice as readily as the axial primary tosyloxy group of (XV).

scholarly journals A Pair of New Polyketide Enantiomers from Three Endolichenic Fungal Strains Nigrospora sphaerica, Alternaria alternata, and Phialophora sp

2016 ◽  
Vol 11 (6) ◽  
pp. 1934578X1601100 ◽  
Author(s):  
Jun-Wei He ◽  
Chuan-Xi Wang ◽  
Li Yang ◽  
Guo-Dong Chen ◽  
Dan Hu ◽  
...  
Keyword(s):  
Diffraction Analysis ◽  
Alternaria Alternata ◽  
Spectroscopic Methods ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fungal Strains ◽  
The Absolute ◽  
Modified Mosher’S Method

A pair of new enantiomeric polyketides, (-)- and (+)-nigrosporaol A (1a and 1b), along with one related known compound, (±)-alternarienoic acid (2), were isolated from three endolichenic fungal strains, Nigrospora sphaerica (No.83-1-1-2), Alternaria alternata (No.58-8-4-1), and Phialophora sp.(No.96-1-8-1). Their structures, including the absolute configurations, were elucidated on the basis of spectroscopic methods, X-ray diffraction analysis, and the modified Mosher's method.

The chemical constituents of Australian Flindersia species. XIX. Triterpenoids from the leaves of F. bourjotiana F. Muell

1966 ◽  
Vol 19 (3) ◽  
pp. 455 ◽  
Author(s):  
GJW Breen ◽  
E Ritchie ◽  
WTL Sidwell ◽  
WC Taylor
Keyword(s):  
Chemical Constituents ◽  
Chemical Degradation ◽  
Spectroscopic Methods ◽  
The Absolute ◽  
Absolute Stereochemistry

From the leaves of Flindersia bourjotinna F. Muell. there were isolated sitosterol, triacontanol, lupeol, germanicol, germanicone, and four new triterpenoids, the bourjotinolones A, B, and C, and bourjotone. By chemical degradation and spectroscopic methods, the structures of these substances were shown to be 21,24-epoxy-23,25-dihydroxytirucall-7-en-3one, 23,24-dihydroxytirucalla-7,25-dien- 3-one, 25-chloro-23,24-dihydroxytirucall-7-en-3-one, and 25,26,27-trisnortirucall-7- ene-3,23-dione, respectively. Bourjotinolone C is almost certainly an artefact but bourjotinolone B and bourjotone are less likely to be. From biogenetic and N.M.R. spectral considerations, the absolute stereochemistry of the new triterpenes may be deduced.

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