Five new indole alkaloids from the leaves of Rauvolfia yunnanensis.

Five new indole alkaloids, rauvoloids A-E (1-5), together with two known ones, raucaffrinoline (6) and perakine (7) were isolated from the leaves of Rauvolfia yunnanensis. Their structures were elucidated by extensive spectroscopic methods. Structurally, rauvoloids A (1), B-C (2-3) and D (4) with unusual substitution patterns (no substitution, Cl and (1E)-3-oxo-butenyl, respectively) at C-20, are the first examples of perakine-type alkaloids with C18 and C22 skeletons.

Microbial transformation of diosgenin by filamentous fungus Cunninghamella echinulata.

Microbial transformation of diosgenin (1) by suspended-cell cultures of the filamentous fungus Cunninghamella echinulata CGMCC 3.2000 was investigated. Incubation of the substrate diosgenin (1) with this fungus led to the isolation of three products: two known compounds, (25R)-spirost-5-en-3ß,7ß,12ß-triol and (25R)-spirost-5-en-3ß,7ß,11α-triol, and a new compound (25R)-spirost-5-en-3ß,7α,11α-triol. The structural elucidations of the three compounds were achieved mainly by the MS, 1D and 2D NMR spectroscopic methods and comparison with known compounds. C. echinulata CGMCC 3.2000 has not been used before in the biotransformation of diosgenin.

Anticancer activity of diterpenoids from Amoora ouangliensis and Amoora stellato-squamosa.

A new ent-halimane-type diterpene, named 5(10),14-ent-halimadien-3beta,13S-diol (1), was isolated from the bark of Amoora ouangliensis and its chemical structure determined on the basis of spectroscopic analysis. Additionally, ten other diterpenoids were obtained from A. ouangliensis and A. stellato-squamosa. The bioactive experiments of all compounds against AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) cells were documented.

Steroidal saponins and cytoxicity of the wild edible vegetable-Smilacina atropurpurea.

Four new steroidal saponins, smilacinoside A (1), B (2), C (3), and D (4), together with three known saponins, funkioside D (5), aspidistrin (6) and 26-O-beta-d-glucopyranosyl-22-methoxyl-(25R)-furost-5-en-3beta,26-diol 3-O-beta-d-glucopyranosyl-(1-->2)-beta-d-glucopyranosyl-(1-->4)-beta-d-galactopyranoside (7) were isolated from the dried tender aerial parts of Smilacina atropurpurea (Franch.) Wang et Tang. The structures of new compounds were elucidated as diosgenin 3-O-alpha-l-rhamnopyranosyl-(1-->2)-O-beta-d-galactopyranoside (1), diosgenin 3-O-alpha-l-rhamnopyranosyl-(1-->3)-[6-O-palmitoxyl]-O-beta-d-galactopyranoside (2), 26-O-beta-d-glucopyranosyl-(25R)-furost-5-en-3beta,22xi,26-triol 3-O-alpha-l-rhamnopyranosyl-(1-->2)}-beta-d-galactopyranoside (3) and 26-O-beta-d-glucopyranosyl-22-methoxyl-(25R)-furost-5-en-3beta,26-diol 3-O-alpha-l-rhamnopyranosyl-(1-->2)-beta-d-galactopyranoside (4) on the basis of chemical methods and detailed spectroscopic analysis, including 1D and 2D NMR techniques and single-crystal X-ray diffraction, respectively. Six of these compounds and MeOH extract were tested for their in vitro cytotoxicity toward K562 human tumor cells by an improved MTT method. Smilacinoside A, funkioside D and aspidistrin exhibited significant in vitro cytotoxicity against K562 with IC(50) values of 1.09, 2.93 and 0.47microg/mL, respectively.

Chemical constituents from the roots of Homonoia riparia.

A new compound and twelve known compounds were isolated from the ethyl acetate extract of the roots of Homonoia riparia Lour, which are used in folk medicine for treatment of hepatitis, bellyache and scald, by the method of silica gel column chromatography repeatedly with a gradient of PE-EtOAc, PE-Me2CO, CHCl3-Me2CO, CHCl3-MeOH. Their structures were identified as a new compound 1-oxo-aleuritolic acid (1), and twelve known compounds aleuritolic acid (2), 3-acetoxy-aleuritolic acid (3), taraxerone (4), taraxerol (5), methyl 3-acetoxy-12-oleanen-28-oate (6), 3-acetoxy-12-oleanen-28-ol (7), ursolic acid (8), lupenol (9), 3beta-acetoxy-lupenol (10), cleomiscosin A (11), chrysophanol (12), and gallic acid (13), which were obtained from this plant for the first time, by the spectroscopic techniques of NMR, HMBC, IR and MS, separately. Among the cytotoxicities evaluation of compounds 1 -3 towards AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) tumor cells was assayed by MTT methods with cis-dichlorodiamminoplatinum (DDP) used as positive control. Compound 2 exerted weak activity against AGZY 83-a with the IC50 value of 33.055 microg x mL(-1), while 1 and 3 showed no activity to these two cell lines.

Anticancer activity of tirucallane triterpenoids from Amoora dasyclada.

A new tetranortriterpene 3alpha-acetoxy-24,25,26,27-tetranortirucalla-7-ene-23(21)-lactone (3), and eleven other compounds were isolated from the twigs of Amoora dasyclada. The structure of compound 3 was identified on the basis of spectroscopic data, and the bioactive experiments of 1 and 3-5 against AGZY 83-a (human lung cancer cells) and SMMC-7721 (human liver cancer cells) are documented. Among them, compound 5 exhibited a strong activity against SMMC-7721.

[Steroidal constituents from Dioscorea parviflora].

AIM: To study the chemical constituents of Dioscorea parviflora. METHODS: The chemical constituents were isolated by silica gel and RP-18 column chromatography, and their chemical structures were elucidated by IR, NMR and MS. RESULTS: Eleven steroides have been isolated from EtOH extract of Dioscorea parviflora and identified as isonarthogenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (I), diosgenin-diglucoside (II), prosapogenin A of dioscin (III), dioscin (IV), deltonin (V), deltoside (VI), methyl deltoside (VII), diosgenin 3-O-beta-D-glucopyranosyl (1-->3)-beta-D-glucopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-beta-D-glucopyranoside (VIII), parvifloside (IX), methyl parvifloside (X), diosgenin (XI), and a mixture of beta-sitosterol and stigmasterol. CONCLUSION: Compound X is a new compound. Compounds VII and X were methyl ethers of VI and IX, respectively, and may be produced during isolation. Compound I is isolated from Dioscorea L., and II, IV from Dioscorea parviflora for the first time.

Four new oleanane type saponins from Morina nepalensis var. alba.

Four new oleanane type saponins, monepalosides G-J (1-4), were isolated from the water-soluble part of the whole plant of Morina nepalensis var. alba Hand-Mazz. On the basis of chemical and spectroscopic evidence, their structures were determined as 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-alpha-L-arabinopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranoside (monepaloside G, 1), 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-beta-D-xylopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranoside (monepaloside H, 2), 3-O-alpha-L-arabinopyranosyl-(1 --> 3)-[beta-D-glucopyranosyl-(1 --> 2)]-alpha-L-arabinopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranoside (monepaloside I, 3), 3-O-beta-D-glucopyranosyl-(1 --> 4)-beta-D-glucopyranosyl-(1 --> 3)]-alpha-L-arabinopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1 --> 6)-beta-D-glucopyranoside (monepaloside J, 4), respectively. Two-dimensional NMR spectra, including H-H COSY, HMQC, 2D HMQC-TOCSY, HMBC and ROESY were utilized in the structure elucidation and complete assignments of 1H and 13C NMR spectra.

Three new hecogenin glycosides from fermented leaves of Agave americana.

Eight steroidal compounds, including three new hecogenin glycosides, agamenosides D-F, were isolated from the fermented leaves of Agave americana. The structures of the new steroidal saponins were elucidated by spectroscopic data and chemical methods. The activity of the isolated compounds on deformations of mycelia germinated from conidia of Pyricularia oaryzae P-2b was evaluated.

Steroidal saponins from rhizomes of Tupistra wattii Hook. f.

Chemical examination of the fresh rhizomes of Tupistra wattii HOOK. f. led to the isolation of three new steroidal saponins, wattoside G (1), H (2), and I (3), together with one known steroidal saponin, (25S)-1beta,3beta,4beta-trihydroxyspirotan-5beta-yl-O-beta-D-glucopyranoside (4). The structures of 1-3 were established to be (25R)-1beta,2beta,3beta,5beta-tetrahydroxyspirostan-4beta-yl-O-beta-D-xylopyranoside (1), (24S,25S)-24-[(beta-D-glucopyranosyl)oxy]-1beta,2beta,3beta,4beta,5beta,7beta-hexahydroxyspirostan-6-one (2), and (24S,25S)-1beta,3beta-dihydroxy-5beta-spirostan-24-yl-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (3) on the basis of detailed analyses of physical, chemical, and spectral data. The isolated compounds were evaluated for cytotoxic activity against the cancer cell line K562 in vitro.

A new ergostanol saponin from Dioscorea deltoidea Wall var. orbiculata.

From the fresh rhizomes of Dioscorea deltoidea Wall var. orbiculata, a novel ergostanol saponin, orbiculatoside A (1), was isolated and identified as 3-O-beta-D-glucopyranosyl-ergost-5-ene-3beta, 26-diol-26-O-beta-D-glucopyranosyl(1-->3)-[beta-D-glucopyranosyl(1-->2)-beta-D-glucupyranosyl(1-->6)]-beta-D-glucopyranoside by various NMR techniques in combination with chemical methods. The new saponin showed strong activity against Pyricularia oryzae, with a MMDC (minimum morphological deformation concentration) value of 28.04 micromol/l and was cytotoxic to cancer cell line K562, HCT-15, A549, HT1080, and A2780a in vitro.

[A new steroidal glycoside from fermented leaves of Agave americana].

OBJECTIVE: To investigate the constituents of fermented leaves of Agave americana, and discover new compounds. METHOD: Compounds were purified with silica gel and C8 reverse--phase silica gel column chromatography. The structures were elucidated by chemical and spectroscopic evidence. RESULT: Three steroidal compounds were obtained and their structures were identified as (25R)-5 alpha-spirostan-3 beta, 6 alpha, 23 alpha-triol 6-O-beta-D-glucopyranoside(1), (25R)-5 alpha-spirostan-3 beta, 6 alpha, 23 alpha-triol-3, 6-di-O-beta-D-glucopyranoside (cantalasaponin-1) (2) and (25R)-5 alpha-spirostan-3 beta, 6 alpha, 23 alpha-triol(hongguanggenin) (3). CONCLUSION: Compound 1 is new compound, named agamenoside C.