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Four new tricarbocyclic diterpenes 2–5 containing the bicyclic [4.3.1] ring system found in floridicin (1), and an additional four dicarbocylic terpenes 6–9 containing the same bicyclic moiety, have been isolated from the soft coral, Xenia florida. Their structures were elecidated by spectroscopic means.

Seven new diterpenoids with an opened A-ring containing an aliphatic acid, called azamilides A—G (1—7), have been isolated from an acetone extract of Xenia sp. and their structures elucidated on the basis of spectroscopic analysis.

The structures of nine new xenia diterpenoids, xeniatine A (1), xeniatine A epoxide (2), isoxeniatines A (3) and B (4), and xeniaethers A (5) and B (6), together with three methoxyacetals 7–9, from a soft coral Xenia species have been elucidated.

Seven new labdane-type glucosides with antibacterial activity have been isolated from Viburnum suspensum. Their structures were elucidated by spect

Floridicin 1, a diterpene containing a [4.3.1] bicyclic ring system, has been isolated from the soft coral Xenia florida, and represents a new class of tricarbocyclic diterpenes.

Two new xenia diterpenoids, xeniatine A (1) and xeniaether A (2), the latter containing a tetrahydrofuran, have been isolated from a soft coral, Xenia sp.

Ten new labdane-type diglucosides, gomojosides A–J, have been isolated from Viburnum suspensum , and their structures elucidated by spectroscopic methods. Five of gomojosides isolated showed potent antibacterial activity.

A cyclopropene-ring-containing fatty acid ester, methyl (R)-2-hydroxysterculate, was isolated from Hibiscus rosa-sinensis along with methyl sterculate and malvalate. The stereochemistry of the asymmetric carbon at C-2 was determined as R by applying a dibenzoate chirality method, and a mild air oxidation afforded two conjugated enone isomers accompanying a ring opening.

Five new iridoids and related glucosides have been isolated from the methanol extract of Catalpa bignonioides root, along with a new phenylethanoid diglycoside. In addition, known iridoid glucosides, catalposide, amphicoside, 6- O -veratryl catalposide and minecoside were identified.

Four new monoterpenoids including two iridoid glucosides, 8-hydroxy-2,6-dimethyl-(2E,6E)-octadienoic acid, glucopyranosyl ester of 8-hydroxy-2,6-dimethyl-(2E,6E)-octadidenolic acid, 8,10-dihydroxy-2-methyl-(2E,6E)-octadienoyl catalpol and 6-O-4″-hydroxy-3″-methoxy-benzoyl ajugol have been isolated from the methanol extract of the root and leaves of Radermacia sinica. Specioside, minecoside, nemoroside I and amphicoside were also identified.

Two new fatty acid methyl esters having an enone ether group were isolated from the root bark of Hibiscus rosa-sinensis along with three known cyclopropenoids. The new compounds, methyl ( E )-11-methoxy-9-oxo-10-nonadecenoate and ( E )-10-methoxy-8-oxo-9-octadecenoate, were chemically correlated to the corresponding cyclopropenoids. propenoids.

A unique symmetrical diphenylmethane derivative, 1,1-bis-(3′,5′-dimethyl-2′-hydroxyphenyl)-2-methylpropane, was isolated from the root bark of Metasequoia glyptostroboides ; it inhibited the growth of some bacteria.

Seven new xenia diterpenes have been isolated from the soft coral, Xenia florida. Four of them possess a bicyclic [4.3.1] ring system. The three others, which contained a cyclononane skeleton with an epoxide, seem to be precursors for diterpenes with a bicyclic [4.3. 1] ring system.

Two new xenia diterpenoids, xeniatine A (1) and xeniaether A (2), the latter containing a tetrahydrofuran, have been isolated from a soft coral, Xenia sp.

Two new non-bitter iridoid glucosides have been isolated from Viburnum suspensum , and their structures elucidated by spectroscopic methods.

The absolute configuration of the asymmetric carbon (C-2) of methyl 2-hydroxysterculate was determined as R by applying the dibenzoate chirality method.

Air oxidation of cyclopropane fatty acid methyl esters, methyl sterculate and malvalate, resulted in the cleavage of cyclopropene ring, respectively, to afford a pair of conjugated enones containing a terminal methylene group.

A new growth inhibitor was isolated from light-grown radish seedlings and its structure determined by spectral data as 3-( E )-(methylthio)methylene-2-pyrrolidinethione. Above concentrations of 30 mg/l, it inhibited hypocotyl growth in the etiolated cress seedling test.

A new acylated flavonol glycoside quercetin 3-α-arabinopyranoside-2″-gallate, having antibacterial activity, has been isolated from the leaves of Lasiobema japonica. Quercetin, hyperin and guaijavarin were also identified.

Floridicin 1, a diterpene containing a [4.3.1] bicyclic ring system, has been isolated from the soft coral Xenia florida, and represents a new class of tricarbocyclic diterpenes.

Three new bitter iridoid glycosides having an 8,10,11-oxygen substituted iridoid skeleton with an isovaleryl moiety at C-1, have been isolated from the ether and ethyl acetate soluble fractions of the leaves of Viburnum furcatum . Two of them had a glucose moiety at C-11 of the iridoid skeleton and a p -coumaroyl group linked to C-6 of the sugar, and they were found to be geometrical isomers about the double bond of the p -coumaroyl† moiety. The third one was characterized as a alloside of the same aglycone.

A new bitter triterpene ester glucoside have been isolated along with known bitter triterpene glucoside peduncloside and some minor triterpenes ulsolic acid, rotundic acid, and rotungenic acid from...

Denticulatolide, an ichthyotoxic cembranoid diterpene bearing acetoxy, α-methylene γ-lactone, and cyclic peroxide functions, has been isolated from the soft coral Lobophytum denticulatum. The structure (1) has been determined by spectral and chemical evidence and X-ray crystallographic method.

Two new triterpenes have been isolated from the fruits of Ilex rotunda along with three known triterpenoids ulsolic acid, rotundic acid and peduncloside. Their structures were characterized as 3β,19α,24-trihydroxyurs-12-ene-28-oic acid and 3β,19α-dihydroxyurs-12-ene-23,28-dioic acid by spectral and chemical means.

Four new bitter iridoid glucosides, including three bis-iridoids, were isolated from Viburnum urceolatum and their structures elucidated. They are composed of loganin or deoxyloganin as the aglucone esterified with either aromatic glucoside or with glucose in the 4-position.

In the reaction with tosyl chloride in pyridine, the meso isomer (2a) of bis[2-hydroxy-1-(2,6-dimethyl-4-methoxyphenyl)ethyl] ether rearranged to give arylacetaldehyde (3) and 2-arylmethyl-4-aryl-1,3-dioxolane (4), and the racemic isomer (2b) afforded 3, 4, and 2,6-diaryl-1,4-dioxane. The aryl migration in this reaction has been confirmed by the use of the deuterated compounds, 2a-D and 2b-D, respectively, substituted with deuteriums at the 2,2-positions.

A new steroid ester, azedarachol, from the root bark of Melia azedarach has been identified as an antifeedant against a Japanese insect pest and the structure has been assigned as 2α,3α,16β-trihydroxy-5α-pregnane 20 R -methacrylate.

Graucin A, a new bitter limonoid, has been isolated from the root bark of Evodia grauca Miq. as well as the known limonoids limonin, rutaevin and limonin diosphenol. Its structural and stereochemical assignments were made using NMR (COSY and NOESY), and CD spectroscopy, which indicated the uncommon 5β-H configuration of this new compound. Rutaevin was also recognized to be a 5β-H limonoid.

3, 5-Diphenylisoxazole and 2, 5-diphenyloxazole were regioselectively carbonylated under an atmosphere of carbon monoxide after the formation of arylpalladium(II) intermediates, to give bioactive o-benzoates substituted by isoxazole and oxazole rings in good yields.

8-Nonynoic, 9-decynoic acids and their methyl esters were isolated for the first time as natural products from Hibiscus rosa-sinensis . They were inhibitors of the germination of lettuce seeds and were synthesized via o -nitrophenyl selenides.

Four novel aliphatic esters have been isolated in trace amounts from the stem bark of Hibiscus rosa-sinensis and are characterized as methyl 10-oxo-11-octadecynoate, methyl 8-oxo-9-octadecynoate, methyl 9-methylene-8-oxoheptadecanoate and methyl 10-methylene-9-oxooctadecanoate. The first two compounds inhibited the germination of lettuce seeds.

The structures of lobohedleolide (1) and (7Z)-lobohedleolide (2), two new cembranolides containing the α,β-unsaturated carboxylic acid system isolated from the Japanese soft coral Lobophytum hedleyi Whitelegge, were elucidated from spectral and chemical evidence, and the absolute configuration of (1) was determined by X-ray analysis of its p-bromophenacyl ester (9). Lobohedleolide (1) showed growth inhibition of the in vitro Hella cells.

From the methanolic extract of the leaves of Viburnum urceolatum a new bitter monoterpene diglycoside, urceolide, has been isolated in addition to several known compounds. The structures were elucidated by spectroscopic and chemical methods.

The reaction of 2,6-dimethyl-4-methoxybenzyl alcohols, ethyl ethers, and acetates, possessing electrondonating and -withdrawing groups at the benzylic position, with bromine water was studied at different temperatures. The reaction was strongly affected by the electronegativity of a benzyl substituent to afford bromination products of aromatic nuclei and 2,4-dibromo-3,5-dimethylmethoxybenzene along with 2,4,6-tribromo derivatives formed by the cleavage of C–C bond.

Eight terminal acetylenic fatty acids from 5-hexynoic to 12-tridecynoic acids and their methyl, ethyl, and isopropyl esters were synthesized via o-nitrophenyl selenides. These acids and esters all showed inhibitory effect on lettuce seed germination and seedling growth. The effect was dependent on the number of carbon atoms in acetylenic chain. 8-Nonynoic acid showed potent activity, and its methyl ester was the most effective among the test compounds. In addition, the acids showed antifungal activity which increased as the number of carbon atoms increased.

ニセアカシヤの葉のフラボノイド成分には1925年服部の得たアカシイン(I)および1954年にFreudenbergの見いだしたアカセチソートリオシド(III)がある。著者らはニセアカシヤの葉のメタノール抽出液のペーパークロマトグラフから,これらの成分以外になお2種の微量フェノール性成分の存在することが予想されたので,それらの微量成分を単離し,主としてぺーパークロマトグラフによって検索を試み,アピゲニン-ビオシド(II),mp257°～258℃とアピゲニン-トリオシド(IV),mp196°～200℃を得て,その構造を明らかにした。さらにこれらのフラギノイド成分のほかに多量のn-ヘキサコシルアルコールを得た。

A total synthesis of seneciphyllic acid, the necic acid of the Senecio alkaloid seneciphylline, is reported.

ニセアカシヤの心材成分については1931年にSchmidtらはロピネチン(VIII)を見いだし,3,7,3',4',5'-ペンタオキシフラボンの構造を与えた。Freudenbergは1954年に心材成分を再検討し,ロピネチン(VIII)のほかに新たにジヒドロロピネチン(IX)を得てその構造を明かにした。著者らはペーパークロマトグラフによって,これらの二つのフラボノイド成分以外になお数種のフェノール性成分の存在が予想されたので,それらの成分の徹底的な検索を試みて,メタノール抽出成分からβ-レゾルシン酸(I),β-レゾルシン酸メチル(II),4,2,,4'-トリオキシカルコン(III)リクリチゲニン(IV),プテイン(V),ブチン(VI),3,4,5,2'4'-ペンタオキシカルコン(VII),ロピネチン(VIII),ジヒドロロピネチン(IX)の9種の成分物質を単離し,構造を明らかにした。これらの中で4,2',4'-トリオキシカルコンおよび3,4,5,2'4'-ペンタオキシカルコンは天然から今回はじめて得られたものである。

(±)-Retusaminic acid has been synthesized from diethyl 1-methylacetonylmalonate and resolved by means of cinchonidine. The synthesized enantiomer was shown to be identical with natural retusaminic acid.

A new iridoid acetylalloside, 2′,3′- O -diacetylfurcatoside Calong with two known iridoid glucosides, furcatoside A and adoxoside, have been isolated from Viburnum japonicumand their structures elucidated. The two former compounds are bitter to the taste.

The racemic and meso bis(1-mesitylethyl) ethers were synthesized. The optical resolution of the dicarboxylic acid derivative showed that the high-melting compounds were racemic in form and the low-melting isomers meso in form.

A new natural substance, 2,3-dihydroxy-2,4-cyclopentadien-1-one, was isolated from the seeds of white clover along with many known compounds.

From the methanol extract of the leaves of Viburnum phlebotrichum, a new bitter monoterpene glucoside has been isolated in addition to three known

A new spiro-bis-γ-lactone glucoside was isolated from the leaves of Viburnum dilatatum and its structure was elucidated on the basis of spectral and chemical evidence.