Triterpenoid saponins of Acanthopanax nipponicus leaves.

Five new triterpenoid saponins, nipponosides A-E (1, 3-6), were isolated from Acanthopanax nipponicus leaves, along with a known saponin, kalopanaxsaponin G (2). Nipponosides A-E were characterized as the 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta -D-glucopyranosyl ester of 3-oxohederagenin, oleanolic acid 3-O-beta-D-glucopyranoside, gypsogenin 3-O-beta-D-glucopyranoside, 3beta,23,29-trihydroxyolean-12-en-28-oic acid, and 3beta,20alpha, 23-trihydroxy-30-nor-olean-12-en-28-oic acid, respectively. The structures of these new compounds were based on chemical and spectral methods.

[Isolation and structure elucidation of cirensenosides Q and R].

Two new saponins (cirensenoside Q and R) were isolated from the leaves of Oplopanax elatus. Their structures were elucidated as follows: Q, gypsogenin 3-O-beta-glucopyranosyl-28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranoside; R, 3 beta-hydroxylup-20(29)-ene-23-al-28-oic acid 3-O-beta-D-glucopyranosyl-28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranoside, respectively.

Steroidal glycosides from the subterranean parts of Liriope spicata var. prolifera.

In a continuation of phytochemical studies on the underground organs of Liriope spicata var. prolifera, four new steroidal glycosides, lirioproliosides A-D, along with two known compounds, 25(S)-ruscogenin 1-O-[alpha-L-rhamnopyranosyl(1-->2)[beta-D-xylopyranosyl (1-->3)]-beta-D-fucopyranoside and ophiopogonin A, were identified. The structures of lirioproliosides A-D were established by a combination of spectroscopic and chemical methods as 25(S)-ruscogenin 1-O-[alpha-L-rhamnopyranosyl(1-->2)][beta-D-xylopyranosyl (1-->3)]-beta-D-fucopyranoside-3-O-alpha-L-rhamnopyranoside, 25(S)-ruscogenin 1-O-[3-O-acetyl-alpha-L-rhamnopyranosyl(1-->2)]-beta-D-fucopyranoside, 25(S)-ruscogenin (1-O-[2-O-acetyl-alpha-L-rhamnopyranosyl (1-->2)]-beta-D-fucopyranoside and ruscogenin (1-O-[2-O-acetyl-alpha-L-rhamnopyranosyl(1-->2)]-beta-D-fucopyranoside, respectively. Among these steroidal glycosides, ophiopogonin A and lirioprolioside B, and lirioproliosides C and D, were isolated as epimeric pairs.

[Isolation and structure elucidation of cirensenosides O and P from the leaves of Oplopanax elatus Nakai].

Two new triterpenoid saponins were isolated from the leaves of Oplopanax elatus Nakai. By measuring physical and chemical constants and spectral data, their structures were elucidated as 3-epi-oleanolic acid 28-O-alpha-L-rhamnopyranosyl (1-->4)-beta-D- glucopyranosyl (1-->6)-beta-D-glucopyranoside; 3-O-beta-D-glucopyranosyl betulinic acid 28-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside and named as cirensenosides O and P, respectively.

Oleanolic acid saponins from root bark of Aralia elata.

Three new oleanolic acid glycosides, tarasaponins I-III, were isolated as their methyl esters from the root bark of Aralia elata together with four known glycosides, the methyl esters of chikusetsusaponins IVa, IV, 28-desglucosyl-chikusetsusaponin IV and pseudoginsenoside RT1. Tarasaponins I-III were characterized as oleanolic acid 3-O-[beta-D-glucopyranosyl(1-->3)][alpha-L-arabinofuranosyl(1-->4)[- beta-D-glucuronopyranoside, oleanolic acid 3-O-[beta-D-xylopyranosyl(1-->2)][beta-D-galactopyranosyl(1-->3)]-beta- D-glucuronopyranoside and beta-D-glucopyranosyl oleanolate 3-O-beta-D-galactopyranosyl(1-->3)-beta-D-glucuronopyranoside, respectively.

Saponins from leaves of Acanthopanax sieboldianus.

Two new triterpenoid saponins named sieboldianoside A and B were isolated from the leaves of Acanthopanax sieboldianus together with five known triterpenoid saponins, kalopanax-saponins A and B, saponin A, CP3, sapindoside B, and a known flavonol glycoside, kaempferol 3-O-rutinoside. On the basis of chemical and spectral evidence, the structures of the new saponins (sieboldianoside A and B) were concluded to be alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)- beta-D-glucopyranosyl esters of hederagenin and oleanolic acid 3-O-beta-D- xylopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopy ranosides, respectively.

Six new triterpenoidal glycosides including two new sapogenols from Albizziae Cortex. V.

Six new triterpenoid glycosides called julibrosides A1-A4, B1 and C1 were isolated from Albizziae Cortex, the dried stem bark of Albizzia julibrissin Durazz. Their structures were determined based on spectral and chemical evidence. Julibrosides B1 and C1 had new sapogenols, designated julibrogenin B and C, respectively, while julibrosides A3 included N-acetyl-D-glucosamine as a sugar component.

Isolation of a new phenazine antibiotic, DOB-41, from Pseudomonas species.

A new phenazine antibiotic, DOB-41, was isolated from the culture broth of a Pseudomonas strain. The antibiotic obtained as yellow crystals showed UV maxima at 255 nm and 370 nm. A molecular formula, C19H18N2O6, was indicated by elemental analysis and mass spectrometry. The structure was elucidated by X-ray diffraction analysis. The antibiotic exhibited inhibitory activity against Gram-positive bacteria, and antitumor effect against leukemia P388 in mice.

Antihepatotoxic Actions of Ginsenosides from Panax ginseng Roots1.

The antihepatotoxic effects of ginsenosides, saponins from PANAX GINSENG, and their aglycones were investigated utilizing carbon tetrachloride (CCl (4))- and galactosamine (GalN)-induced cytotoxicity in primary cultured rat hepatocytes. Prominent protective actions were found with 20( S)-ginsenoside-Rh (2), 20( R)-ginsenoside-Rg (3) and prosapogenin of ginsenoside-Ro, 20( R)- and 20( S)-ginsenoside-Rs in CCl (4)-produced cytotoxicity, and 20( S)-ginsenoside-Rh (1) and prosapogenin of 20( S)-ginsenoside-Rs were effective in preventing GalN-induced liver cell damage. The antihepatotoxic effects of chikusetsusaponins, saponins of PANAX JAPONICUS, were also examined. The structure-activity relationship is discussed.