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Several phytotoxic metabolites, including a novel compound chaetoglobosin O, were isolated from Cylindrocladium floridanum Sobers et Seymore. The structure of chaetoglobosin O, including its absolute configuration, was determined by a spectroscopic analysis and chemical correlation. Purified chaetoglobosins A, C, and O showed potent growth-inhibition activity against alfalfa seedlings.

Fungitoxic compounds from the roots of tomato stocks, Taibyo Shinko No.1, were determined as four unsaturated hydroxy fatty acids [(13S)-13-hydroxy-(9Z, 11E)-9, 11-octadecadienoic acid, 13-hydroxy-(9E, 11E)-9, 11-octadecadienoic acid, (9S)-9-hydroxy-(10E, 12Z)-10, 12-octadecadienoic acid and 9-hydroxy-(10E, 12E)-10, 12-octadecadienoic acid], a dicarboxylic acid (azelaic acid), a quinone (2, 6-dimethoxy-p-benzoquinone) and five phenolic compounds (vanillin, syringaldehyde, p-hydroxybenzaldehyde, p-hydroxybenzoic acid, vanillic acid). It can be considered that the fungitoxic compounds related to resistance of the tomato stock against soil-borne disease were alkaloids, but not these universal compounds in plants.

Six new steroidal alkaloids were isolated from roots of a hybrid of Lycopersicon esculentum x L. hirsutum and their structures elucidated as 5α-tomatidan-3-one, (23 R )-23-acetoxytomatidine, (23 S )-23- acetoxysoladulcidine, (23 S ,25 S )-23-acetoxy-5α,22α N -spirosolan-3β-o1; 22,26-epimino- 16β,23-epoxy-23α-ethoxy-5α,25αH-cholest-22( N )-ene-3β,20α-diol and 22,26-epimino-16β, 23-epoxy-5α,22βH,25αH-cholestane-3β,23α-diol, respectively.

The chemical structure of tuberonic acid (3-oxo-2-[5-hydroxy-2-cis-pentenyl]-cyclopentane-1-acetic acid), which is the aglycone of a potato tuber-inducing substance isolated from potato leaves, is closely related to that of jasmonic acid. The potato tuber-inducing activities of jasmonic acid and related substances were compared. Jasmonic acid and its methyl ester showed strong tuber-inducing activity. Comparison of the tuber-inducing activities of various analogues of jasmonic acid suggests that those parts of the structure that are indispensable for the activity are the carboxyl group or its esters at the C-1 position, the pentenyl side chain at C-2 and the oxygen atom at C-3.

(–)-Probetaenone I (1) has been synthesized by an intramolecular Diels–Alder reaction and, thereby, its structure has been clearly confirmed; in the biosynthesis of betaenone B (2) the stereochemistry of the C-8 hydroxylation of (1) was proved to involve retention of configuration.

(–)-Probetaenone I (1) has been synthesized by an intramolecular Diels–Alder reaction and, thereby, its structure has been clearly confirmed; in the biosynthesis of betaenone B (2) the stereochemistry of the C-8 hydroxylation of (1) was proved to involve retention of configuration.

Later oxidation processes in biosynthesis of betaenone B (2) were examined by a simple method involving preparation of isotopically labelled probetaenone I (1) from [1-14C]- and [1,2-13C]-acetate and [S-13CH3]methionine in Phoma betae and their efficient conversion to (2); the results show that (1) is an intermediate for formation of (2).

Three phytotoxins named pyrenochaetic acids A, B and C were isolated from culture filtrates of Pyrenochaeta terrestris, and the structures were determined to be 4-crotonoyl-3-methoxy-5-methylbenzoic acid (I), 4-(3-hydroxybutyroyl)-3-methoxy-5-methylbenzoic acid (II) and 4-butyroyl-3-methoxy-5-methylbenzoic acid (III), respectively. Their phytotoxicities were demonstrated in bioassays.

The roots of Ezo-no-gishigishi (Rumex obtusifolius) contained a high concentration of malonic acid (more than 100 mg/100 g fr.wt) and oxalic acid (15-45 mg/100g fr.wt). The effect of several compounds isolated from the roots of R. obtusifolius on the growth of some fungi, bacteria and lettuce seedlings was examined. It is suggested that one reason for the resistance to decomposition of roots of R. obtusifolius in soil is the existence of organic acids and derivatives of naphthalene and anthraquinone in the tissue.

Seven novel fungitoxic sesquiterpenoids, chokols A, B, C, D, E, F and G, were isolated from stromata of Epichloe typhina on Phleum pratense. Their structures were determined by spectroscopic methods. The absolute configuration of chokol E was elucidated by its CD spectrum with Eu(fod)3 and a chemical correlation with epicyclonerodiol oxide.

γ-Glutamyl peptides and acidic cysteine derivatives were found in low concentrations in asparagus shoots. However, the presence of α- and β-aspartylaspartic acid, α-aspartyl-glutamic acid, γ-glutamylaspartic acid, γ-glutamylglutamic acid, γ-glutamyltyrosine, S-(2-carboxy-n-propyl)-l-cysteine and S-(1,2-dicarboxyethyl)-l-cysteine was demonstrated in the acidic amino acids fraction of asparagus shoots.

The isolation and structural determination of fungitoxic compounds from roots of eggplant stocks, Taibyo VF, were performed. Three sesquiterpenes (solavetivone, lubimin and epilubimin) and five phenolic compounds [vanillin, ethyl ferulate, ethyl p-coumarate, ethyl caffeate, p-hydroxybenzoic acid, 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-1-propanone] were isolated. The content of solavetivone in the stock was about five times that of a eggplant.

The annual shoots of apple and pear trees which accumulated a high concentration of arginine during the dormant stage also contained N α -acylarginine derivatives. N α -(2-Hydroxysuccinyl)arginine, N α -(3-hydroxysuccinyl)arginine and N α -oxalylarginine were found in apple trees, and N α -succinylarginine and N α -(2-carboxymethyl-2-hydroxysuccinyl)arginine, besides the former three, were found in pear trees. N α -(3-Hydroxysuccinyl)arginine, N α -oxalylarginine and N α -succinylarginine are new arginine derivatives.

The activity and specificity of γ-glutamyltranspeptidase in immature seeds of some leguminous plants did not reflect the γ-glutamyl peptide pattern

The bitterness of triterpenoid components, which were isolated from the fruiting body of Ganoderma lucidum, was examined. The structural similarity of the intensely bitter compounds was also elucidated, from which it was concluded that the spatial relationship of the hydrophobic methyl groups to the three functional oxygen atoms plays an important role in generating the bitterness.

Two new phenolic amides, grossamide (7) and N-cis-feruloyl tyramine (2), have been isolated from the roots of bell pepper (Capsicum annuum var. grossum) together with p-aminobenzaldehyde (1), N-trans-feruloyl tyramine (3), N-trans-p-coumaroyl tyramine (4), N-trans-feruloyl octopamine (5), and N-trans-p-coumaroyl octopamine (6).

New three conjugated serotonins were isolated from safflower meal (carthamus tinctorius L.). On the basis of spectral properties and chemical evidence, their structures were determined as N-feruloylserotonin (4), N-(p-coumaroyl)serotonin (5) and N-(p-coumaroyl)serotonin mono-β-d-glucopyranoside (6), The known compounds, 2-hydroxyarctiin (2), matairesinol mono-β-d-glucoside (1) and acacetin (3) were also isolated and identified.

The structure of a new indole derivative, serotobenine (1), from sfflower meal (Carthamus tinctorius> L.) is proposed based on 1H- and 13C-NMR spectral data and X-ray crystallography. The known compounds N-feruloyltryptamine (2) and N-(p-coumaroyl)tryptamine (3) were also isolated and identified.

Four novel triterpenoids, epoxyganoderiol A (1), B (2) and C (3) and ganoderal B (4), and one novel steroid (6) were isolated from the fungus Ganoderma lucidum, with the known ganoderol B (5) and 6...

By spectroscopic data, the structures of two new phytotoxins, altiloxins a and b from Phoma asparagi sacc., the incitant of stem blight disease on asparagus are elucidated.

By a simple process, 3-methoxyjuglone (= 8-hydroxy-2-methoxy-1,4-naphthoquinone; 9) has been synthesized from 1,2,4-trimethoxybenzene (5) and converted, after prenylation, to α-caryopterone (1; Scheme 1), a pyranojuglone pigment from Caryopteris clandonensis. On the other hand, juglone (= 5-hydroxy-1,4-naphthoquinone; 12) was regioselectively prenylated at C(2) via its 1-methoxy-cyclohexa-1,3-diene adduct 15(Scheme 2). The 2-prenyljuglone (4) thus formed led to 1 after oxidation and other reactions.

On the basis of spectroscopic data and chemical reaction, structures 1 , 2 and 3 are proposed for solanapyrones A, B and C, phytotoxins from the fungus Alternaria solani , parasite of potato.

Of several phytotoxins isolated from culture filtrates of Phoma betae Frank PS-13, an incitant of leaf spot disease of sugar beet, three have been identified as aphidicolin, 3-deoxyaphidicolin and aphidicolin-17-monoacetate. Aphidicolin is a selective inhibitor of eukaryotic DNA polymerase alpha (Ikegami et al. (1978) Nature 275, 458-460). Consequently, we studied the action mechanism of 3-deoxyaphidicolin and aphidicolin-17-monoacetate. These aphidicolin analogues markedly inhibited the in vivo DNA synthesis of sea urchin embryos and HeLa cells but not RNA and protein syntheses. Only DNA polymerase alpha, not DNA polymerase beta and gamma, was inhibited by these drugs. The mode of action of these analogues on DNA polymerase alpha from the sea urchin was competitive inhibition with respect to dCTP with Ki values of 0.44 micrograms/ml for deoxyaphidicolin and 0.89 micrograms/ml for aphidicolin monoacetate, respectively. None of the other three dNTPs competed with these drugs. A similar inhibitory mode was observed using the enzyme from HeLa cells and toad oocytes. These drugs at a concentration of 2 micrograms/ml caused a delay in the cleavage of fertilized eggs of the sea urchin and decomposition before blastulation, indicating the possibility of achromosomal cleavage because of the absence of DNA synthesis. Based on the above, it is concluded that these analogues can be used as other inhibitors of eukaryotic DNA synthesis and DNA polymerase alpha.

Stereoselective synthesis of (±)-senepoxyde and (±) crotepoxide is described starting from 2-hydroxymethyl-1, 4-benzoquinone through the retro-Diels-Alder reaction.

The polyphenols in red clover were examined from the standpoint of disease resistance to the northern anthracnose. The polyphenols were identified as trans-clovamide [N-trans-cafFeoyl-3-(3, 4-dihydroxyphenyI)-l-aIanine] (VI), cis-clovamide [N-cis-caffeoyI-3-(3, 4-dihy-droxyphenyl)-l-alanine] (X) and phaselic acid (trans-caffeoyl-l-malic acid) (II). trans-Clovamide and cis-clovamide are new compounds.

The isolation of four phenolic amides, four phenolic compounds and an aromatic amine from the roots of eggplant is described. The phenolic amides were identified as N-trans-feruloyl tyramine (V), N-trans-p-coumaroyl tyramine (VII), N-trans-feruloyl octopamine (VIII) and N-trans-p-coymaroyl octopamine (IX). The three amides V, VIII and IX are new compounds. Furthermore, four phenolic compounds were identified as vanillin (I), isoscopoletin (II), ethyl caffeate (IV) and ferulic acid (VI). The aromatic amine was identified as p-aminobenzal-dehyde (III).

Four fungitoxic C-18 hydroxy unsaturated fatty acids ( 1 )–( 4 ) have been isolated from stromata of Epichloe typhina . Their structures including the absolute configuration have been elucidated from spectral data.

l-Ng-Methylarginine, l-Ng,Ng-dimethylarginine and ethanolamine were isolated from basic amino acids fraction of broad bean (Vicia faba L.) seed. The presence of Ng,N′g-dimethylarginine was also suggested.

The structures of eight novel triterpenoids, ganoderiol C (1), D (2), E (3), F (4), G (5), H (6), I (7), and ganolucidic acid E (8), isolated from the fruiting body of Ganoderma lucidum were determined by spectroscopic methods. In addition, the absolute configuration at C-23 of ganolucidic acid D (9) was determined from the CD spectrum of its p-dimethylaminobenzoate derivative.

The synthesis of dimethyl esters of dl-O,O′-dimethylfukiic acid (11) and dl-O,O′-dimethylepifukiic acid (12) are described.

Efficient synthesis of (±)-nanaomycin A and (±)-frenolicin from a versatile intermediate is described.