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A rapid, simple, sensitive, gradient and reproducible, reverse-phase high-performance liquid chromatographic method was developed for the quantitative estimation of bioactive alkaloids, lysergol and chanoclavine in the seeds of Ipomoea muricata. The clavine alkaloid, lysergol, is a bioenhancer for the drugs and nutrients. The samples were analyzed by reverse-phase chromatography on a Waters spherisorb ODS2 column (250 × 4.6 mm, i.d., 10 µm) using binary gradient elution with acetonitrile and 0.01 m phosphate buffer (NaH2PO4) containing 0.1% glacial acetic acid at a flow rate of 0.8 mL/min, a column temperature of 25 °C and UV detection at λ 254 nm. The limits of detection (LOD) and quantitation (LOQ) were 0.035 and 0.106 µg/mL for lysergol and 0.039 and 0.118 µg/mL for chanoclavine, respectively. Standard curves were linear in the range of 2–10 µg/mL (r > 99) for both analytes. Good results were achieved with respect to repeatability (RSD

A previous study showed that together with the festuclavine synthase FgaFS, the old yellow enzyme FgaOx3 from Aspergillus fumigatus catalyzed the conversion of chanoclavine-I aldehyde to festuclavine in the biosynthesis of ergot alkaloids. In the absence of FgaFS, a mixture containing two compounds with a ratio of 7:3 was detected in the enzyme assay of FgaOx3. NMR experiments including (DQF)-COSY, HSQC, HMBC and NOESY identified their structures as E/Z isomers of N-methyl-N-[(5R,10R)-10-(2-oxo-propyl)-2,4,5,10-tetrahydrobenzo[cd]indol-5-yl]formamide and proved the migration of the formyl group at C-8 in chanoclavine I-aldehyde to N-6 in the identified products. Copyright © 2011 John Wiley & Sons, Ltd.

Clavines and D-lysergic acid-derived alkaloid amides and alkaloid peptides are two different families of compounds that have the indole-derived tetracyclic metergoline ring system in common. Previous work has shown that D-lysergic acid is biosynthetically derived from clavine alkaloids. Recent cloning and analysis of the ergot alkaloid biosynthesis gene cluster from the D-lysergic acid peptide (ergopeptines)-producing Claviceps purpurea, has shown that it most probably contains all genes necessary for D-lysergic acid synthesis as well as those that encode the assembly of D-lysergic acid peptides, such as ergotamine. To address the role of the oxygenase genes of alkaloid-gene clusters, the only cytochrome P450 monooxygenase gene of this cluster was inactivated by disruption. The resultant mutant accumulated agroclavine, elymoclavine, and chanoclavine in substantial amounts but not ergopeptines. Feeding the mutant with D-lysergic acid restored ergopeptine synthesis; this suggests a block in the conversion of elymoclavine to D-lysergic acid. The gene was designated cloA (for encoding a clavine oxidase, CLOA). Retransformation of the mutant with the intact cloA gene also restored ergopeptine synthesis. These data show that CLOA catalyses the conversion of clavines to D-lysergic acid, it acts as a critical enzyme in the ergot alkaloid gene cluster, and bridges the biosynthesis of the two different families of alkaloids.

The content of ergot alkaloids (ergovaline and chanoclavine), and their production in October 1996 and during the period May–September 1997, were investigated in seventeen ecotypes of perennial ryegrass (Lolium perenne L.) and in nineteen ecotypes of meadow fescue (Festuca pratensis Huds.), naturally infected with Neotyphodium spp. The ecotypes were collected in the north-eastern part of the Czech Republic. In 1996 the content of ergovaline in the ecotypes of perennial ryegrass ranged from 0·00 to 2·73 μg g–1 dry matter (DM) (one cut), and in 1997 from 0·00 to 4·65 μg g–1 DM (five cuts). In meadow fescue the content of ergovaline varied from 0·00 to 0·61 μg g–1 DM (one cut) in 1996, and in 1997 from 0·00 to 2·31 μg g–1 DM (five cuts). The content of chanoclavine (investigated in 1997 in four cuts only) in perennial ryegrass ranged between 0·00 and 3·39 μg g–1 DM, and in meadow fescue between 0·00 and 2·26 μg g–1 DM. Most ecotypes of L. perenne reacted to the high temperature and heavy rainfall in June and July of 1997 with an enhanced production of ergovaline, whereas the content of chanoclavine was not changed. Such reaction to stress conditions was not observed in the ecotypes of F. pratensis. Large differences in the production of both ergot alkaloids between different ecotypes of both plant species were observed.

β-Galactosides of elymoclavine, chanoclavine, lysergol, 9,10-di-hydrolysergol, and ergometrine were prepared using β-galactosidase from Aspergillus oryzae .

The total enantioselective synthesis of (−)-chanoclavine I 2 in twelve steps from indole-4-carboxaldehyde 4 is described The key-step 3 → 6 which involves the formation of the C ring by creation of the C5-C10 bond is catalyzed by a chiral palladium (0) complexes. The chiral ergoline synthon 6 is produced with an excellent diastereo-and enantioselectivity (up to 95% ee).

Das 13C-angereicherte C-Atom der 4'-(E)-Methylgruppe im 4-(3-Methyl-2-butenyl)tryptophan (3) erscheint bei der Biosynthese in der C-Methylgruppe des Chanoclavins (4) und im C-17 von Agroclavin (5), Elymoclavin (6) und Lysergsaure (7). Incorporation of [4'-(E)-13C]4-(3-Methyl-2-butenyl)tryptophan into Clavine Alkaloids and Lysergic Acid The 13C-enriched C-atom of the 4'(E)-methyl groups of 4-(3-methyl-2-butenyl)tryptophan (3) appears during the biosynthesis at the C-methyl group of chanoclavine (4) and at C-17 of agroclavine (5), elymoclavien (6) and lysergic acid (7).

L-Tryptophan did not exert any influence on peptide alkaloid formation in an ergotamine and in an ergosine-accumulating C. purpurea strain. A different picture was observed in a series of related C. purpurea strains. Tryptophan showed a slight stimulatory effect on the ergotoxine producer Pepty 695/S. A blocked mutant of it, designated as Pepty 695/ch which was able to accumulate secoclavines gave similar results. In a high-yielding elymoclavine strain Pepty 695/e, the progeny of the former one, tryptophan up to a concentration of 25 mM stimulated remarkably clavine biosynthesis. Furthermore, tryptophan could overcome the block of synthesis by inorganic phosphate. Increased specific activities of chanoclavine cyclase but not DMAT synthetase were observed in cultures of strain Pepty 695/e supplemented with tryptophan. 5-Methyltryptophan and bioisosteres of tryptophan were ineffective in alkaloid stimulation. These results are compared with those obtained with the grass ergot strain SD 58 and discussed with the relation to other induction phenomena.

(E)-3-(1-Acetyl-1,5-dihydrospiro[benz[cd]indol-4(3H),2′-[1-3]dioxolan]-5-yl)-2-methylacrylsaureathylester (9) und ahnliche Benz[cd]indol-Derivate werden mit der Zielsetzung einer Chanoclavin-Synthese dargestellt. Synthesis of Benz[cd]indole Derivatives, III. Preliminary Experiments for a Synthesis of Chanoclavine Ethyl (E)-3-(1-acetyl-1,5-dihydrospiro[benz[cd]indol-4(3H),2′-[1-3]dioxolan]-5-yl)-2-methylacrylate and related benz[cd]indole derivatives are synthesized with the aim of a chanoclavine synthesis.

Ergot alkaloides were extracted from seed of native, wild-type morning glories (i.e. Texas red morning glory (Ipomoea hederifoliaL.), cypress vine morning glory (I. quamoclit L.), red morning glory (I. coccinea L.) and palmleaf morning glory (I. wrightii Gray) and quantified by spectrophotometry as ergonovine maleate equivalents. A horticultural variety (I. tricolor Cav. cv. Heavenly Blue) was utilized for comparison and contained 0.052% total alkaloids in the seed. Total ergot alkaloids in these four native, wild-type morning glories ranged from 0.003 to 0.005% (i.e. 5.97 to 9.77% of the alkaloids found in Heavenly Blue seed) and were not present in sufficient quantity to induce any psychotomimetic hazard. Major alkaloids found in these wild-type morning glory species were separated and identified by two-dimensional thin-layer chromatography and co-chromatography with authenticated standards. Alkaloids identified included chanoclavine, elymoclavine, penniclavine, ergonovinine, agroclavine, ergonovine, ergosine and ergosinine. Alkaloids varied between morning glory species.

The racemic alkaloids chanoclavine I (1) and isochanoclavine I (2) have been synthesized stereoselectively from indole-4-carbaldehyde (3) by a sequence of 11 operations in overall yields of 14% and 2.4%, respectively. The key step 6 8(Scheme 2) involves a transient nitrone 7 which undergoes a regio- and stereoselective intramolecular cycloaddition to a 1,2-disubstituted olefinic bond.

SUMMARY The emergence of a new stable strain of Claviceps purpurea is described. The strain formed the sphacelial stage very weakly on rye, and was unlikely therefore to be able to initiate an epidemic under field conditions, but the sclerotia contained chanoclavine as the major alkaloid in contrast to the ergotamine component of the parent strain. Isolates of C. purpurea derived from ryegrass ergots were also shown to parasitize rye.

From a rye ergot alkaloid fraction rich in chanoclavine we isolated three new crystalline alkaloids, each a stereoisomer of the known chanoclavine. Their configurations could be elucidated by NMR.-spectra. According to the nomenclature of the dihydro-d-lysergic acid series the isolated alkaloids are named: chanoclavine-(I) (formerly named chanoclavine), chanoclavine-(II), rac. chanoclavine-(II) and isochanoclavine-(I).

SUMMARY The constituent ergoline alkaloids produced in vitro by a Nigerian strain of Sphacelia sorghi have been identified as dihydroergosine, festuclavine, pyroclavine, dihydroelymoclavine, and chanoclavine. The same alkaloids were present in both the sphacelial stage and the sclerotia when S. sorghi parasitized florets of Sorghum vulgare. The Nigerian fungus appears to be quite different from certain oriental collections bearing the same name, and although forming stromatal initials, failed to develop the sexual stage. Mice successfully raised litters and showed no adverse response when fed on diets containing up to 50% of the ergot sclerotia. The ergot had also no effect on early pregnancy. Some of the alkaloid was excreted in the faeces, but, as injected alkaloid was also shown to be excreted in the faeces, this could have represented alkaloid which had been absorbed from the ingested sclerotia and re-excreted via the bile.

The simple total synthesis of the ergot alkaloids, (±)-norchanoclavine-I, (±)-chanoclavine-I, (±)-isochanoclavine-I, and (±)-agroclavine was achieved by a practical and common synthesis method. A new regio-selective oxidation of the Z-methyl group of the isoprenyl system with selenium dioxide is described.