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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.

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.

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.

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.

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.

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.

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.

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.

From the fronds of Pronephrium triphyllum HOLLT., three new glycosides, named triphyllins A, B and C, were isolated. Their structures were determined as (2R, 4S)-5, 7-di-β-D-glucosyloxy-6-hydroxymethyl-4'-methoxy-8-methylflavan-4-ol, (2R, 4S)-5, 7-di-β-D-glucosyloxy-4'-hydroxy-6-hydroxymethyl-8-methylflavan-4-ol and (2S)-7-β-D-glucosyloxy-5-hydroxy-4'-methoxy-6-methoxymethyl-8-methylflavanone, respectively, on the basis of spectral data and chemical correlations.

The constituents of three Costa Rican ferns of Pteridaceae were investigated. From Jamesonia scammanae A. TRYON, a new pterosin-type compound (I), named jamesonin, along with two pterosin derivatives and six ent-kaurane-type diterpene derivatives were isolated, and I was established as (2R, 3R)-3-hydroxy-6-(2-hydroxyethyl)-2, 7-bishydroxymethyl-2, 5-dimethylindan-1-one by spectroscopic methods. From Dicksonia gigantea KARST., two known pterosin derivatives were isolated, and from Paesia anfractuosa C. CHR., two flavonol glycosides.

Three new ent-kaurane-type diterpenes, I, II and III, were isolated from the fronds of Dipteris conjugata REINW. Their structures were elucidated as 16β, 17-dihydroxy-ent-kauran-19-oic acid, 16β, 17-dihydroxy-19-nor-ent-kauran-18-oic acid and 16β, 17, 18-trihydroxy-ent-kauran-19-oic acid, respectively.

The investigation of four pteridaceous ferns afforded, in addition to known pterosins, six new pterosins and three new pterosides. The structures are elucidated mainly by spectroscopic methods.

From the fronds of Bolbitis subcordata (COPEL.) CHING a new C-methylleucoanthocyanidin was isolated and shown to be (2R, 3S, 4S)-5, 4'-dimethoxy-6, 8-dimethyl-3, 4, 7-trihydroxy-flavan.

Aus den oberirdischen Teilen von Pteris grandifolia L. wurden neben Quercitrin (3, 5, 7, 3', 4'-Pentahydroxy-flavon-3-mono-α-L-rhamnopyranosid) zwei neue Flavonol-acetyl-glykoside, d.h., 3"-O-Acetyl-quercitrin und 4"-O-Acetyl-quercitrin isoliert und identifiziert.

Im Zusammenfang mit der chemotaxonomischen Untersuchungen der Gattung Pteris und der verwandten Gattungen wurden aus den oberirdischen Teilen von Pteris dispar KUNZE neben der schon bekannten ent-11α-Hydroxy-15-oxo-Kaur-16-en-19-carbonsaure (III) vier neue ent-Kaurantyp-Diterpene, namlich ent-11α-Hydroxy-15-oxo-16S-Kauran-19-carbonsaure (I), ent-11α-Hydroxy-15-oxo-16R-Kauran-19-carbonsaure (II), ent-7α, 9-Dihydroxy-15-oxo-Kaur-16-en-19, 6β-olid (IV) und ent-7α, 9-Dihydroxy-15-oxo-16S-Kauran-19, 6β-olid (V), isoliert.

The fronds of Plenasium banksiifolium (PR.) PR. contain stigmastan-3β, 5α-diol-6-one and its C28-homolog, which are previously unreported in nature, together with the known compounds, ecdysone, ecdysterone, astragalin, stigmastan-3β, 5α, 6β-triol and its C28-homolog.

From the fronds of Dennstaedtia scandens (BLUME) MOORE a new acylglucose was isolated and identified as 1, 4-di-O-p-coumaroyl-β-D-glucose. As further extractives, the following compounds were isolated : p-hydroxybenzoic acid, methyl p-coumarate, pinocembrin-7-O-β-D-glucoside, vitexin and isovitexin.

From the fronds of Protowoodsia manchuriensis (HOOK.) CHING a new sesquiterpene was isolated and its structure elucidated as 6β-hydroxy-isodrimenin by spectroscopic investigations and chemical transformations.

Die erneute Untersuchung von Pteris inaequalis BAKER var. aequata (MIQ.) TAGAWA ergab zwei neue Verbindungen, Hydroxymaltol-3-O-β-D-glukosid (I) und 2-Deoxy-D-glukonsauremethylester (II). I wurde ebenfalls aus Pteris formosana BAKER isoliert.

From the fronds of Polystichum tripteron (KUNZE) PR. a new norcarotenoid glycoside was isolated and shown to be (6R, 7E, 9R)-9-hydroxy-megastigma-4, 7-dien-3-one-9-O-β-D-glucoside. The fronds of Dennstaedtia wilfordii (MOORE) CHRIST. contain the same glucoside.