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Investigation of the root bark extract of Entandrophragma angolense led to identification of two gedunin-type limonoids 5-hydroxy-7-deacetoxy-7-oxogedunin ( 1 ) and 5,6-dehydro-7-deacetoxy-7-oxogedunin ( 2 ), and three methyl angolensate derivatives, 6-deacetoxydomesticulide D ( 3 ), 6-deacetoxydomesticulide D 21-methylether ( 4 ), and entangosin ( 5 ), together with known compounds, methyl angolensate ( 6 ), 6-acetoxymethyl angolensate ( 7 ) and secomahoganin ( 8 ). Their structures were established by extensive NMR experiments in conjunction with mass spectrometry. Entangosin is a rare example of a limonoid derivative having a fully O -substituted furan moiety.

Six phragmalin limonoids, named tabulalin and tabulalides A-E, were isolated from the root bark of Chukrasia tabularis (Meliaceae). Their structures were determined by spectroscopic methods, and their antifeedant properties evaluated.

Four limonoids were isolated from Melia toosendan together with two known limonoids, nimbolinin B and its 1-deacetyl derivative. Among the new limonoids included one skeletal spiro-, one ring- C-seco nimbolinin-type, and two trichilinin-type apo-euphol-triterpenoids derivatives. Their structures were determined on the basis of spectroscopic data.

Two new degraded limonoids, azedararide and 12alpha-acetoxy fraxinellone, were isolated together with two known degraded limonoids, fraxinellone and fraxinellonone, as ichthyotoxic substances from the root bark of Melia azedarach. Their structures were elucidated by spectroscopic and chemical means.

Three new ring C-seco-limonoids, nimbolidins C-E, were isolated from the root bark of Melia toosendan along with two known seco-limonoids, nimbolidin B and salannin. These compounds have properties as insect feeding inhibitors. Their structures were elucidated by spectroscopic means.

Two new insect antifeeding limonoids, trichilins K and L, were isolated from the stem bark of Melia toosendan along with five known limonoids, trichilins H, I and J, azedarachin A and 12-O-acetyl-azedarachin B. Their structures were elucidated by spectroscopic means and their antifeeding properties were examined with the larvae of Spodoptera eridania.

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

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.

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.

A new limonoid, azedarachin C, was isolated as an insect antifeedant from the root bark of Chinese Melia azedarach and the structure was elucidated by spectroscopic means.

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

The structure of nishindaside, an iridoid from the leaves of Vitex negundo, has been revised. In addition, a new isomer, isonishindaside has been isolated from V. cannabifolia.

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.

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.

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.

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.

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.

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.

A new phenol alloside, p -hydroxyphenyl β- D -alloside, has been isolated from the leaves of Viburnum wrightii in addition to several known compounds. The structures were elucidated by spectroscopic and chemical methods.

A new acetylated coumarin glucoside has been isolated from the leaves of Viburnum suspensum and determined as 2′,6′- O -diacetylscopolin on the basis of spectral and chemical evidence.