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Five new chromone C-glycosides have been obtained from the leaves of Baeckea frutescens. They are: 6-β-C-glucopyranosyl-5,7- dihydroxy-2-isopropylchromone, 8-β-C-glucopyranosyl-5,7-dihydroxy-2-isopropylchromone, 6-β-C-glucopyranosyl-5,7-dihydroxy- 2-methylchromone, 6-β-C-(2′-galloylglucopyranosyl)-5,7-dihydroxy-2-isopropylchromone and 8-β-C-(2′-galloylglucopyranosyl)-5,7-dihydroxy-2-isopropylchromone.

Three new compounds; 4'-O-β-D-glucopyranosyl rosmarinic acid (2), 4,4'-O-di-β-D-glucopyranosyl rosmarinic acid(3) and 2R-O-(4'-O-β-D-glucopyranosyl caffeoyl)-3-(4-hydroxyphenyl) lactic acid named as 4'-O-β-D-glucopyranosyl isorinic acid (4) were isolated together with rosmarinic acid (1) from the fruit of Helicteres isora L. (Sterculiaceae), an Indonesian medicinal plant. The structures of these compounds, including the absolute stereochemistry of 4, were elucidated by spectroscopic analysis and chemical means. Compound 3 had greater scavenging activity against superoxide anion produced with xanthine and xanthine oxidase (XOD) than rosmarinic acid (1).

Six triterpenoids were isolated from the callus tissues of Paeonia japonica, P. lactiflora and P. suffruticosa. Four of the compounds are new from a natural source: 11α,12α-epoxy-3β,23-dihydroxyolean-28,13β-olide, 3β-hydroxy-11-oxo-olean-12-en-28-oic acid, 3β-hydroxy-oleana-11,13(18)-dien-28-oic acid and 3β,23-dihydroxy-oleana-11,13(18)-dien-28-oic acid. The postulated biosynthetic sequence of these compounds is discussed and the triterpenoids produced from the three callus tissues have been compared from a chemotaxonomical standpoint.

A new chemotype of Microlepia marginata, P-type strain, was found in the Central districts of Japan. The two main constituents were characterized to be 2 beta,15(R),16-trihydroxy-ent-pimar-7-en-3-one (fumotoshidin A) and 3 alpha-alpha-L-arabinofuranosyloxy-15(R),16-dihydroxy-ent-pimar+ ++-7-ene (fumotoshidin arabinoside). The young fronds of this strain have reddish stripes, which is a common feature to Y-type strains also containing ent-pimarane-type glycosides.

Three new trimeric proanthocyanidins were isolated in lactone form (1L, 2L and 3L) and acid form (1A, 2A and 3A) from the fronds of both Arachniodes sporadosora NAKAIKE and A. exilis CHING. Their structures were determined by spectroscopic methods and thiolytic degradation.

From the frond of Oreopteris quelpaertensis , a novel chalcone-like product has been isolated as a mixture of keto—enol tautomeric isomers, along with its dimeric form, and their structures were determined by extensive 2D NMR spectroscopy or X-ray diffraction. Isoquercitrin was also obtained from this fern.

A novel 2-tetralol-type xyloside, named asplenoside, was isolated from the fronds of Asplenium wilfordii. The structure was determined as (6R)-5, 6, 7, 8-tetrahydro-6-β-D-xylopyranosyloxy-2-naphthalenecarboxylic acid by chemical and spectral means. Application of the glycosylation shift rule in 13C-NMR spectroscopy to the determination of the absolute configuration is described.

Four lignans, blechnic acid (1), 7-epiblechnic acid (3), 8-epiblechnic acid (6) and brainic acid (2), were isolated from six Blechnaceous ferns, Blechnum orientale, Struthiopteris amabilis, S. niponica, Woodwardia orientalis, W. prolifera and Brainea insignis. Their structures were determined by spectroscopic methods and chemical conversion.

A new anthraquinone glycoside, physcion 8-O-β-rutinoside, has been isolated from the bark of Rhamnus libanoticus together with emodin, its 6-O-α-l-rhamnoside and 8-O-β-d-glucoside, and kaempferol.

From the roots of Polygala senega L. six new oligosaccharides, called senegoses J-O, were isolated and their structures were elucidated by spectroscopic and chemical means. These oligosaccharides were esterified with acetic, benzoic, p-coumaric and ferulic acids.

Two new flavonol glycosides have been isolated from the fruit of Turkish Rhamnus thymifolius (Rhamnaceae) and their structures were elucidated as kaempferol-3-O-alpha-L-rhamnopyranosyl(1-->3)-(4-O-acetyl)-O-alpha-L- rhamnopyranosyl-(1-->6)-O-beta-D-galactopyranoside and kaempferol-4'-O-alpha-L-rhamnopyranosyl(1-->3)-O-alpha-L-rhamnopyranosyl (1-->6)-O-beta-D-galactopyranoside based on spectral and chemical evidence.

Seven known iridoid glycosides (1∼7), together with one known diterpenoid (8) were isolated from the aerial parts of Borreria latifolia K. Schum. (Rubiaceae) collected in Indonesia, and their structures were identified byspectroscopic methods.

A new acetophenone glycoside and two new naphthalide glycosides have been isolated from the bark of Turkish Rhamnus libanoticus together with 7-hydroxy-5-methoxyphthalide 7- O -β-D-glucoside. The structures of the new compounds were elucidated by spectroscopic methods as 2,6-dihydroxy-4-methoxyacetophenone 2- O -β- rutinoside, 8,9-dihydroxy-6-methoxynaphthalide 8- O -β-rutinoside, 8,9-dihydroxy-6-methoxynaphthalide 8- O -/3b-D glucoside, respectively.

From the aerial parts of Lindsaea chienii CHING a new diterpenoid glycoside (lindokaurenoside C) has been isolated together with lindsaea acid, creticoside A, trans-cinnamic acid and p-hydroxy-trans-cinnamic acid. From spectroscopic evidences and chemical reactions the structure of the new glucoside has been established as ent-2α, 13-dihydroxykaura-16-ene 2-O-β-D-glucoside.

Aus den oberirdischen Teilen von Pteris vittata L. wurden zwei neue Lignanglykoside, d. h., cis-Dihydro-dehydro-diconiferylalkohol-9-O-β-D-Glukosid (I) und Lariciresinol-9-O-β-D-Glukosid (III) isoliert und identifiziert.

The fronds extracts of Glaphyropteridopsis erubescens (WALL.) COPEL. contain besides the already known flavonol glycosides (afzelin and quercitrin) three new flavan-4-ol glycosides, eruberin A (I), B (II) and C (III), which belong to a new type of proanthocyanidin. By means of spectroscopic and chemical methods, the structures 5, 7-dihydroxy-4'-methoxy-6, 8-dimethyl-2", 4 (S)-oxido-2 (R)-flavan-5-β-D-glucopyranoside (I), 4 (S), 5, 7-trihydroxy-4'-methoxy-6, 8-dimethyl-2 (R)-flavan-5, 7-O-β-D-diglucopyranoside (II) and 5, 7-dihydroxy-4 (S), 4'-dimethoxy-6, 8-dimethyl-2 (R)-flavan-5, 7-O-β-D-diglucopyranoside (III) are proposed. Eruberin C (III) may be an artifact.

Chemical studies of three representatives of the genus Pseudophegopteris (Thelypteridaceae) revealed that the genus is characterized by the occurrence of unusual flavonoids with a modified B-ring related to protogenkwanin (VII). From P. hirtirachis HOLTT., three novel compounds, protogenkwanone (I), tetrahydroprotogenkwanone (II) and tetrahydroprotogenkwanin (III), were isolated, along with protogenkwanin 4'-O-β-D-glucoside (VI). From P. subaurita CHING, two new acylated glucosides of protogenkwanin, protogenkwanin 4'-O- (2-O-acetyl) -β-D-glucoside (IV) and 4'-O- (6-O-acetyl) -β-D-glucoside (V), were obtained, together with I, II and VI. From P. bukoensis HOLTT., IV, V and VI were isolated, in addition to apigenin 7-O-α-L-rhamnoside and kaempferol. The structures of the new compounds were determined by means of spectroscopic methods and chemical transformations.

From the fronds of Dennstaedtia distenta, new flavan-3-ol (catechin) derivatives, distenin (1), its dimer (2) and its trimer (3), were isolated in addition to vitexin. On the basis of the spectroscopicand chemical evidence, their structures were established as (2R, 3R)-flavan-3, 5, 7-triol (1), distenin-(4β→8)-distenin (2) and distenin-(4β→8)-distenin-(4β→8)-distenin (3), respectively.

From the fronds of Pteris longipes DON two known and five new ent-kaurane type diterpenes were isolated. The structures of the new diterpenes, pterokaurene L1, L2, L3, L4 and pterokaurane L5, were established respectively as ent-9-hydroxy-15-oxo-kaur-16-en-19-oic acid, ent-9, 15α-dihydroxy-kaur-16-en-19-oic acid, ent-9-hydroxy-kaur-16-en-19-oic acid, ent-12α, 15α-dihydroxy-kaur-16-en-19-oic acid and ent-11α, 16α-epoxy-16R-kauranoic acid by spectroscopic methods, some chemical transformations and X-ray crystallographic analysis.

Six new compounds were isolated from the methanol extract of Arachinoides standishii OHWI. Chemical and physicochemical studies showed their structures to be 1-(2, 4, 6-trimethoxyphenyl)-but-trans-2-en-1-one (I), 5, 7-dimethoxy-2-methylchromanone (II), 2-ethyl-5, 7-dimethoxychromanone (III), 5-hydroxy-dimethoxy-2-methyl-chromanone (IV), 3-β-D-allosyloxy-1-(2-hydroxy-4, 6-dimethoxyphenyl)-butan-1-one (V) and 8-carboxy-6-hydroxy-2, 5-dimethyl-2a, 3, 4, 5-tetrahydroacenaphthene (VI). Compound VI, named ryomenin, is the first sesquiterpene reported to possess a tetrahydroacenaphthene skeleton.

From the aerial parts of Dennstaedtia wilfordii (MOORE) CHRIST. three new pterosins (pterolacton A, B and dennstopterosin) and two new pterosides (pterolacton A 3-O-β-D-glucoside and pterolacton A 3-O-β-D-(4'-p-coumaroyl)-glucoside) have been isolated together with pterosin A, D and L. Their structures have been established from spectroscopic evidences and chemical reactions.

A novel pterosin-type dinorsesquiterpene, mukagolactone (I), was isolated from the fronds of Monachosorum arakii TAGAWA (Pteridaceae), along with three new dinorsesquiterpene dimers, monachosorins A (II), B (III) and C (IV). Their structures were elucidated on the basis of spectroscopic and chemical data. Compound II may have been formed by an aldol-type condensation of 6-(2-hydroxyethyl)-5, 7-dimethylindan-1-one and the corresponding 5-formyl compound. The reduction of II afforded III, and the acid isomerization of II gave IV.

A chemical assay of ptaquiloside, the major carcinogen of Pteridium aquilinum , based on two-dimensional TLC-densitometry, was devised. The contents of ptaquiloside and related compounds in the fern collected at four places at different seasons were compared and the epidemiological implications of the results are discussed. The behaviour of ptaquiloside on treatment with acid, alkali, light and heat was examined and the instability of the compound, especially under alkaline conditions, was confirmed. The distribution of ptaquiloside and ptaquiloside-like substances in the Pteridaceae was examined by the use of the chemical assay and the modified Ames' test, and widespread occurrence of such compounds was revealed.

From the fronds of Microlepia marginata (PANZER) C. CHR. five new ent-kaurane type diterpene glycosides, microlepin (I), 17-O-acetylmicrolepin (VIII), 6'-O-acetylmicrolepin (IX), 4-epi-microlepin (X) and 6'-O-α-L-rhamnopyranosyl-4-epi-microlepin (XVIII) were isolated and their structures were elucidated by spectroscopic methods and some chemical reactions. Microlepin and 4-epi-microlepin possesses the structures 16α, 17, 19-trihydroxy-ent-kaurane 19-O-β-(4'-O-methyl)-D-glucopyranoside and 16α, 17, 18-trihydroxy-ent-kaurane 18-O-β-(4'-O-methyl)-D-glucopyranoside.

The fronds of Scypholepia hookeriana J. SM. (Microlepia hookeriana (WALL.) PRESL) afforded four oligoglycosides of a new ent-pimarane-type diterpene, which were named hookerosides A (I), B (II), C (III) and D (IV). The structures were elucidated by means of chemical reactions and spectroscopic methods to be 3α-[O-(3-O-methyl)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranosyloxy]-12α-[(3-O-methyl)-β-D-quinovopyranosyloxy]-(I), 3α-[O-(3-O-methyl)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranosyloxy]-12α-[β-D-fucopyranosyloxy]-(II), 3α-[O-(3-O-methyl)-β-D-glucopyranosyl-(1→2)-α-L-arabinofuranosyloxy]-12α-[β-D-fucopyranosyloxy]-(III) and 3α-[O-β-D-fucopyranosyl-(1→3)-O-β-D-fucopyranosyl (1→2)-α-L-arabinofuranosyloxy]-12α-[β-D-fucopyranosyloxy]-(IV) ent-pimara-8 (14), 15-diene.

Three piscicidal pregnanes including two known defense substances of water beetles and four pregnane glycosides having the same aglycone as that of teikaside A were isolated from the roots of Apocynum venetum L. var.basikurumon HARA and their structures were determined.

Two new compounds, II and III, were isolated, together with 4-hydroxynicotinamide, from the fronds of both Arachniodes nigrospinosa and A. festina. The structures of II and III were elucidated as (E)-1-(2, 3, 4, 6-tetramethoxyphenyl) but-2-en-1-one and (E)-1-(2, 3, 4, 6-tetramethoxyphenyl) pent-2-en-1-one, respectively. Ryomenin (I) was isolated from the fronds of A. mutica.

Die Untersuchungen von Pteris fauriei HIERON. und P. inaqualis BAKER var. aequata (MIQ.) TAGAWA ergeben acht neue Indan-1-on-Derivate (Pterosin W, X, Pterosid W, X, S, T, U und Onitisin-2'-O-β-D-Glukosid), deren Strukturen durch spektroskopische Methoden geklart werden.

From the fronds of Alsophila spinulosa TRYON biflavonoids Hegoflavone A (I) and B (II) were isolated and their structures were elucidated by spectroscopic analysis and chemical degradation to be 2, 3-dihydro-3'''-hydroxy-6, 6'''-biapigenin (I) and 2, 3-dihydro-6, 6'''-biluteolin (II) respectively. These are the first reports of a C-6/C-6'''-linked biflavonoid in nature.

Ein neues Indan-1-ol-Derivat aus den oberirdischen Teilen von Pteris wallichiana AGARDH. wurde als 1 (R), 2 (R), 3 (R)-1, 3-Dihydroxy-2, 5, 7-trimethyl-6-hydroxyathyl-indan-1-O-β-D-glukosid (I) und ein neues Indan-1-on-Derivat aus den oberirdischen Teilen von P. semipinnata L. als 3-Hydroxy-6-hydroxymethyl-2, 5, 7-trimethyl-indan-1-on (XII) identifiziert.