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Three new glucosidic constituents (1–3) were isolated from the methanolie extract of Perilla frutescens. Two of these compounds (t and 2) were jasmonoid glucosides and were determined to be 5’-β-D-glueopyranosyloxyjasmonic acid and 3-β-D-glucopyranosyl-3-epi-2-isocucurbic acid, respectively. The other one (3) was a new glucoside of phenylvaleric acid that was elucidated to be 3-β-D-glucopyranosyloxy-5-phenylvaleric acid. Its aglycone was also found for the first time in nature.

A virG thyA double mutant of Shigella flexneri 2a was constructed as a candidate live-attenuated oral vaccine. In the keratoconjunctivitis model it did not provoke any adverse reaction by itself on guinea pigs' eyes and completely protected them from provoking keratoconjunctivitis. When (2.7–4.8) × 1010 of the vaccine was inoculated intragastrically after 1 day fasting in cynomolgus monkeys three times at weekly intervals, a watery stool was observed at 40% as a side-effect. Upon intragastric challenge after 1 day fasting with 7.5 × 109 of the virulent strain four weeks after the last vaccination, a statistically significant difference was obtained in the mortality rate but not in the morbidity rate between the vaccine and the control group, although the clinical findings were less severe in the vaccine group than in the control group. These results together with the histopathological and immunological findings indicate that the vaccine deserve further detailed studies.

It is generally known that specimens of Carex species plants are resistant to insects and contain a variety of stilbene compounds. Some stilbene oligomers obtained from four kinds of Carex plants were analyzed by mass spectrometry. The electron impact mass spectra, secondary ionization mass spectra, and B/E linked scan spectra were measured to investigate their fragmentations.

Nisamycin, a new manumycin group antibiotic, was isolated from the culture broth of Streptomyces sp. K106. This strain was designated to genus Streptomyces by the taxonomic features. Nisamycin was purified by ethyl acetate extraction, silica gel column chromatography, preparative silica gel TLC, and Sephadex LH-20 column chromatography as a pale yellow powder. Nisamycin is active against Gram-positive bacteria and fungi, and exhibits a cytotoxic activity.

The glycosidic constituents of two varieties of Perilla frutescens have been compared. A new phenylpropanoid glucoside named perilloside E has been isolated from the fresh leaves of the purple type plant. The structure was determined on the basis of spectral and chemical evidence.

It is known that several kinds of pyrrolidine alkaloids with a bis-amide structure are isolated from extracts from leaves and roots of Meliaceae family plants. A fragment ion m/z 85 was found in common in mass spectra of all these compounds. The structure and fragmentation mechanism of the ion were elucidated through high-resolution mass spectra and B/E as well as B2/E linked scan spectra. The fragment ion was also found useful as an index for searching compounds having similar structures.

Three new monoterpene glucosides named perilloside B-D have been isolated from the fresh leaves of Perilla frutescens. The structures were determined on the basis of spectral and chemical evidence.

In addition to neoliacine and neoliacinic acid previously reported, three new germacranolides, named neoliacinolide A, B, and C, were isolated from the leaves of Neolitsea aciculata Koidz., and their structures were elucidated by spectroscopic analysis.

A novel quinone antibiotic named malbranicin was isolated from the culture filtrate and mycelium of Malbranchea cinnamomea TAIM 13T54, a thermophilic fungus. The antibiotic was elucidated to be 6-(1-acetylethyl)-2-methoxy-2,5-cyclohexadiene-1,4-dione by spectral analysis. Malbranicin exhibited antimicrobial and cytotoxic activities against Gram-positive bacteria and mammalian cell lines, respectively.

A new antifungal antibiotic, S-632-C, was extracted with ethyl acetate from the culture filtrate of Streptomyces hygroscopicus S-632 and isolated through a combination of column and preparative thin-layer chromatographies on silica gel. The structure of S-632-C was determined by analysis of 1H and 13C-NMR, MS, UV and IR spectra in comparison with those of S-632-A2 (9-methylstreptimidone). The signals were assigned on the basis of 2D NMR experiments, which involved 1H-1H DQF COSY, HMQC and HMBC spectral analysis. From these results, the chemical structure of S-632-C was elucidated as 6-(3,5-dimethyl-2-oxo-4,6-octadienyl)-4-carbamoylmethyl-3,4, 5,6-tetrahydro-2- pyrone. The antibiotic exhibited exclusively weak in vitro antifungal activity against Saccharomyces spp. and similar cytotoxic activity against KB carcinoma cells, as compared with the glutarimide antibiotic S-632-A2. In addition, this antibiotic had the ability to change the morphology of ras(ts)-transformed NRK cells to that of normal cells, also a characteristic S-632-A2 and B1.

Nisamycin, a novel manumycin group antibiotic, was isolated from the culture broth of Streptomyces sp. K106. Structural elucidation of nisamycin was achieved by detailed NMR spectral analyses and comparison of the NMR data of nisamycin with those of other manumycin group antibiotics. The structure was confirmed by chromic acid oxidation. The absolute stereochemistry of nisamycin was determined to be 4R, 5S and 6R from the CD spectra of nisamycin and chromic oxidation of nisamycin. In addition, some structure activity-relationships were examined.

The structure and stereochemistry of sargassumketone, a novel highly oxygenated ketone isolated from Sargassum kjellmanianum (the marine brown algae), have been elucidated on the basis of the spectroscopic and X-ray diffraction analysis.

Three new germacranolide glycosides, pittosporanoside B1, B2 and B3, have been isolated from Pittosporum tobira Ait, and their structures have been determined by spectral and X-ray crystallographic analyses.

Three new gymnomitrane sesquiterpenoids have been isolated from the liverwort Marsupella emarginata var. patens together with the known (−)-gymnomitrene and (−)-ar-curcumene. Their structures and absolute configurations have been determined on the basis of chemical and spectroscopic evidence as well as from the results of an X-ray analysis of a derivative. We also describe the ring expansion reaction of the gymnomitrane framework and the chemosystematics of the genus Marsupella.

Penicillium sp. NTC-47, which had been isolated from a soil sample, produced novel dihydroquinolinones when cultured with okara (the insoluble residue of whole soybean). These metabolites, 1 and 2, were crystalline products with molecular formulas of C17H17NO5 and C17H17NO4, respectively. The structure of 1 was established to be 3-methoxy-4,5-dihydroxy-4-(4'-methoxyphenyl)-quinolinone by spectroscopic evidence and by an X-ray crystal-lographic analysis. Spectral data indicated the structure of 2 to be 5-deoxy-l. Compound 1 demonstrated toxicity against brine shrimp with an LC50 value of 20μg/ml, but 2 exhibited no activity at a dose of 100 μg/ml.

A new monoterpene glucoside named perilloside A has been isolated from the fresh leaves of Perilla frutescens . Its structure has been characterized on the basis of spectral and chemical evidence.

A new friedelane triterpene alcohol, maytensifolin-C, has been isolated from the stems of Maytenus diversifolia . Its structure was established as 6β-hydroxyfriedelan-3,16,21-trione by spectroscopic methods and single-crystal X-ray analysis.

Monoterpene glucosides, perillosides A and C, obtained from the leaves of Perilla frutescens, were found to be inhibitors of aldose reductase (EC 1.1.1.21) which is considered to be a key enzyme in diabetic complications such as cataract. The apparent type of inhibition of rat lens aldose reductase by perillosides A and C was competitive with respect to glyceraldehyde and their K(i) values were 1.4 x 10(-4) and 2.3 x 10(-4) M, respectively. The type of inhibition by their tetraacetates was non-competitive with respect to the same substrate, although their inhibitory effects were increased by about one order of magnitude compared with those of the perilllosides and the K(i) values were 2.5 x 10(-5) and 7.1 x 10(-5) M, respectively. We also prepared related monoterpene glucosides and their tetraacetates and determined their inhibitory activities towards aldose reductase in order to elucidate the relationship between structure and inhibitory activity.

Nisamycin, a novel manumycin group antibiotic, was isolated from the culture broth of Streptomyces sp. K106. Structural elucidation of nisamycin was achieved by detailed NMR spectral analyses and comparison of the NMR data of nisamycin with those of other manumycin group antibiotics. The structure was confirmed by chromic acid oxidation. The absolute stereochemistry of nisamycin was determined to be 4R, 5S and 6R from the CD spectra of nisamycin and chromic oxidation of nisamycin. In addition, some structure activity-relationships were examined.

The structure and stereochemistry of sargassumketone, a novel highly oxygenated ketone isolated from Sargassum kjellmanianum (the marine brown algae), have been elucidated on the basis of the spectroscopic and X-ray diffraction analysis.

The structure and absolute configuration of a new cyclopentenone derivative, (+)-kjellmanianone, isolated from the brown alga Sargassum kjellmanianum has been determined as 5-carbomethoxy-5-hydroxy-3-methoxy-2-cyclopenten-1-one on the basis of the chemical and spectroscopic evidence and the X-ray analysis.

The structure of a new antitumor antibiotic, myrocin C, from a strain of Myrothecium verrucaria was characterized as a pentacyclic pimarane diterpene composed of a gamma-lactol group and a unique cyclopropane ring on the basis of its physico-chemical properties and spectroscopic data as well as a single-crystal X-ray diffraction analysis of its monoacetyl derivative.

Thirty flavones, four isoflavones and thirteen coumarins were tested as inhibitors of lens aldose reductase, which is believed to participate in the initiation of cataract formation in diabetes. Many were found to be potent inhibitors, and the two most potent ones were axillarin (5,7,3′,4′-tetrahydroxy-3, 6-dimethoxyflavone) and 6,3′,4′-trihydroxy-5,7,8-trimethoxyflavone (LARI 1). These two flavones inhibited aldose reductase purified from rat lens with IC 50 values of 2.6 × 10 −8 and 3.6 × 10 −8 M respectively. They also inhibited aldose reductase purified from bovine lens with ic 50 values of 1.8 × 10 −7 M. The potencies of the two compounds were superior to those of all the previously reported inhibitors of aldose reductase. Inhibition of rat and bovine lens aldose reductases by the two compounds was of a non-competitive type with dl -glyceraldehyde as the variable substrate. Some flavones including axillarin and LARI 1 were found to be poorly or scarcely inhibitory against several adeninenucleotide-requiring enzymes, which are involved in glycolysis and other metabolic reactions. These results obtained show that the two flavones have some features which may be required in clinically useful drugs for diabetic patients. All the potent inhibitors of the compounds tested had a flavone skeleton, one (or two free) hydroxyl(s) in ring C, and more than three hydroxyls (free or methylated) in ring A. The possible relationships of structures to inhibitory potencies of the compounds tested are discussed.

A sesquiterpene aldehyde, (−)-lepidozenal, having a novel trans-fused bicyclo[8.1.0]undecane carbon skeleton has been isolated from the liverwort Lepidozia vitvea, and its structure and absolute configuration have been shown to be (6S,7R)-lepidoza-1(10)E,4E-dien-14-al, on the basis of the chemical and spectral evidence.

Conformational analysis of the dolabellane diterpenoid, 6β-acetoxy-12β-hydroxydolabella-3E,7E-diene containing 1,5-undecadiene, has been achieved by means of molecular mechanics calculations, 1H NMR, and CD spectrometry. The epoxidation products of the diene can be rationalized in terms of the calculated equilibrium conformations.

Two enantiomeric cuparene-type sesquiterpenoids, (R)-(−)-cuparene ( 1 ) and (R)-(−)-δ-cuparenol ( 2 ), have been isolated from the liverwort, Bazzania pompeana . The structures and absolute configurations of the two compounds have been determined.

13C NMR spectra of several 2,3-seco-alloaromadendrane-type acetyl hemiacetals were analysed and the structure of an additional plant growth-inhibitor was determined to be (+)-9α-acetoxyovalifoliene. The biological activity of the new compound is also described.

The structures of two new sesquiterpene glycosides, pittosporanoside A1, and A2, isolated from the title plant were determined on the basis of chemical and spectral evidence and X-ray crystal structure analysis.

A series of ent-sesquiterpenoids corresponding to the optical antipodes of those in higher plants have been isolated from the liverwort Marchantia polymorpha. These sesquiterpenoids provide yet another example of the peculiar stereospecificity of the biogenesis of the liverwort sesquiterpenoids and suggest a special taxonomic position of the liverworts in the plant kingdom.

Sudachiin A was isolated from the green peels of Citrus sudachi Hort. ex Shirai. This structure was deduced to be sudachitin 4′-β-D-glucoside by means of its spectra and degradation; this was confirmed by the synthesis of the one from sudachitin 7-benzyl ether and α-acetobromoglucose via several steps. 4′,5,7-Trihydroxy-3′,6,8-trimethoxyflavone 7-glucoside (sudachitin 7-β-D-glucoside), which was isolated from Sideritis leucantha Cavanilles, was also synthesized from sudachitin and α-acetobromoglucose in a similar manner.

We describe the isolation, structure and biological activity of kaimonolide A, a macrolide plant growth inhibitor, using FAB spectrometry and cosy NMR spectrometry

In the course of an investigation of the constituents of the fungus Sarcodon scabrosus (Phylacteriaceae), we found eight new types of bitter compounds named sarcodonin A∼H. This paper deals with the isolation and structural determination of these compounds from the titles fungus

5,2′-Dihydroxy-6,8-dimethoxyflavone, which had been proposed as the structure of skullcapflavone I isolated from Scutellaria baicalensis Georgi, was synthesized from 2-hydroxy-3,5,6-trimethoxyaceto...

The chemical constituents of the volatile oils from Chrysanthemum indicum, C. yoshinaganthum and C. cuneifolium, three botanically related tetraploid species, are described. By spectroscopic methods, 42 compounds were identified, including 22 monoterpenoids, 17 sesquiterpenoids and 3 acetylenic compounds. The sesquiterpenoids estafiatin (C. yoshinaganthum) and valeranone (C. indicum) have been found for the first time in Chrysanthemum species.

Methyl decanoate, undecanoate, laurate, tridecanoate, myristate, pentadecanoate, palmitate, oleate and stearate were isolated as steam-volatile components from this liverwort. Total amounts of these methyl esters accounted for 75·3 per cent of the steam-volatile substances and methyl palmitate (60%) was the major constituent.

A novel antitumor antibiotic, methylenolactocin, was isolated from the culture filtrate of a new isolate of fungus identified as Penicillium sp. The fermentation yield reached about 100 mg per liter of the broth. Methylenolactocin has the molecular formula of C11H16O4 and possess an exomethylene lactone structure. Its structure was determined to be 3-carboxy-2-methylene-4-nonanolide by spectroscopic data. It is active against some Gram-positive bacteria and it prolongs the life span of mice inoculated with Ehrlich carcinoma.

A new diterpene antitumor antibiotic, myrocin C, has been isolated from the culture filtrate of a soil fungus, Myrothecium verrucaria strain No. 55. The antibiotic was effective against Gram-positive bacteria, fungi and yeasts, and prolonged the life span of mice bearing Ehrlich ascites carcinoma.

Sudachiin A was isolated from the green peels of Citrus sudachi Hort. ex Shirai. This structure was deduced to be sudachitin 4′-β-D-glucoside by means of its spectra and degradation; this was confirmed by the synthesis of the one from sudachitin 7-benzyl ether and α-acetobromoglucose via several steps. 4′,5,7-Trihydroxy-3′,6,8-trimethoxyflavone 7-glucoside (sudachitin 7-β-D-glucoside), which was isolated from Sideritis leucantha Cavanilles, was also synthesized from sudachitin and α-acetobromoglucose in a similar manner.

5,2′-Dihydroxy-6,8-dimethoxyflavone, which had been proposed as the structure of skullcapflavone I isolated from Scutellaria baicalensis Georgi, was synthesized from 2-hydroxy-3,5,6-trimethoxyaceto...

The antiviral activity of a wide range of naturally occurring flavonoids was investigated in vitro. Chrysosplenol B and chrysosplenol C, which are contained specifically in Chrysosplenium plants, and axillarin showed potent antiviral activity, especially against rhinovirus. A comparison of the activities of the compounds tested indicated that 3-methoxyl and 5-hydroxyl groups in the flavone skeleton were both necessary for antiviral activity against rhinovirus, and the activity may also be affected by various groups at other positions. The other flavonoids tested had little or no antiviral activity against herpes simplex virus, influenza virus and rhinovirus. These results suggest that Chrysosplenium plants, which contain large amounts of chrysosplenol B and chrysosplenol C, may be useful as medicinal herbs against the common cold caused by rhinovirus infection. These plants have not so far been used as a medicinal herb or as a folk medicine, as far as is known.

Two simple γ-lactonic cembranolides were isolated from the soft coral Sinularia mayi Luttschw. and structurally elucidated on the basis of spectral and chemical evidence.

Aus den Hexanextrakten vonPlagiochila acanthophylla subsp.japonica wurden (−)-Maalioxid und (+)-Cyclocolorenon isoliert. Diese Verbindungen sind enantromer zu denjenigen, die aus hoheren Pflanzen erhalten worden sind.