Cholinesterase inhibiting withanolides from Withania somnifera

A total of two new (1, 2) and four known (3-6) withanolides were isolated from the whole plant of Withania somnifera. Their structures were elucidated on the basis of spectroscopic techniques and were characterized as 6alpha,7alpha-epoxy-3beta,5alpha,20beta-trihydroxy-1-oxowitha-24-enolide (1), 5beta,6beta-epoxy-4beta,17alpha,27-trihydroxy-1-oxowitha-2,24-dienolide (2), withaferin-A (3), 2,3-dihydrowithaferin-A (4), 6alpha,7alpha-epoxy-5alpha,20beta-dihydroxy-1-oxowitha-2,24-dienolide (5), and 5beta,6beta-epoxy-4beta-hydroxy-1-oxowitha-2,14,24-trienolide (6), respectively. Compounds 2, 3, 5, and 6 displayed inhibitory potential against butyrylcholinesterase, but only compounds 3, 4, and 6 were found to be active against acetylcholinesterase.     

Constituents of Withania somnifera Dun—XIII : The withanolides of chemotype III

Nine new steroidal lactones of the withanolide series (withanolides E-M) have been isolated from the leaves of Withania somnifera Dun (Solanaceae) growing in the southern coastal plane of Israel. This population of W. somnifera constitutes a new chemotype and is designated as chemotype III. The following structures have been assigned to seven of the above compounds:Withanolide G, 20α-hydroxy-1-oxo-20R,22R-witha-2,5,8(14),24-tetraenolide (1); withanolide H, 20α,27-dihydroxy-1-oxo-20R,22R-witha-2,5,8(14),24-tetraenolide (2); withanolide I, 20α-hydroxy-1-oxo-20R,22R-witha-3,5,8(14),24-tetraenolide (3); withanolide J, 17α,20α-dihydroxy-1-oxo-20S,22R-witha-2,5,8(14),24-tetraenolide (4); withanolide K, 17α,20α-dihydroxy-1-oxo-20S,22R-witha-3,5,8(14),24-tetraenolide (5); withanolide L, 17α,20α-dihydroxy-1-oxo-20S,22R-witha-2,5,14,24-tetraenolide (6); withanolide M, 17α,20α-dihydroxy-1-oxo-14α,15α-epoxy-20S,22R-witha-2,5,24-trienolide (7).     

Trypanocidal constituents in plants 6. 1) Minor withanolides from the aerial parts of Physalis angulata

Further study of the methanol extract of the aerial parts of Physalis angulata (Solanaceae) resulted in the isolation of new withanolides, designated physagulins L, M and N, together with known withanolide, physagulin D and flavonol glycoside, quercetin 3-O-rhamnosyl-(1-->6)-galactoside. The chemical structures of these new withanolides were elucidated by detailed spectroscopic analyses to be (20R,22R)-15alpha-acetoxy-5alpha,6beta,14beta,17beta,27-pentahydroxy-1-oxo-witha-2, 24-dienolide, (20S,22S)-15alpha-acetoxy-5alpha,6beta,14alpha,23beta-tetrahydroxy-1-oxo-witha-2,16,24-trienolide and (20S,22R)-15alpha-acetoxy-5beta,6beta-epoxy-14alpha-hydoxy-3beta-methoxy-1-oxo-witha-16,24-dienolide, respectively. All these compounds showed weak trypanocidal activity against trypomastigotes, an infectious form of Trypanosoma cruzi, the etiologic agent for Chagas' disease. Withanolides obtained in the previous paper showed considerable trypanocidal activity, suggesting the structure-activity relationships.     

Withanolide derivatives from the roots of Withania somnifera and their neurite outgrowth activities

Five new withanolide derivatives (1, 9-12) were isolated from the roots of Withania somnifera together with fourteen known compounds (2-8, 13-19). On the basis of spectroscopic and physiochemical evidence, compounds 1 and 9-12 were determined to be (20S,22R)-3 alpha,6 alpha-epoxy-4 beta,5 beta,27-trihydroxy-1-oxowitha-24-enolide (1), 27-O-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (withanoside VIII, 9), 27-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranoside (withanoside IX, 10), 27-O-beta-D-glucopyranosylpubesenolide 3-O-beta-D-glucopyranoside (withanoside X, 11), and (20R,22R)-1 alpha,3 beta,20,27-tetrahydroxywitha-5,24-dienolide 3-O-beta-D-glucopyranoside (withanoside XI, 12). Of the isolated compounds, 1, withanolide A (2), (20S,22R)-4 beta,5 beta,6 alpha,27-tetrahydroxy-1-oxowitha-2,24-dienolide (6), withanoside IV (14), withanoside VI (15) and coagulin Q (16) showed significant neurite outgrowth activity at a concentration of 1 microM on a human neuroblastoma SH-SY5Y cell line.     

Withanolides from Withania adpressa

From the leaves of Withania adpressa, a plant endemic to Sahara of Morocco and Algeria, the novel steroidal lactone (22R)‐14α,15α,17β,20β‐tetrahydroxy‐1‐oxowitha‐2,5,24‐trien‐26,22‐olide (= (15S,17S)‐14,15,17,20‐tetrahydroxy‐22,26‐epoxyergosta‐2,5,24‐triene‐1,26‐dione; 1 ), was isolated, along with three known compounds, withanolides F ( 2 ), J ( 3 ), and oleanolic acid. Their structures were mainly solved by in‐depth 1D‐ and 2D‐NMR (including ADEQUATE) experiments, as well as by HR‐MS analyses and chemical evidence.     

Ajugins C and D,New Withanolides from Ajuga parviflora

The new withanolides ajugin C (=(20R,22R)-4β,14α,20,27-tetrahydroxy-1-oxoergosta-2,5,24-trieno-26,22-lactone; 1 ) and ajugin D (=(20R,22R)-8β,14α,17β,20,27-pentahydroxy-1-oxoergosta-5,24-dieno-26,22-lactone; 2 ) were isolated from the whole plant of Ajuga parviflora. Their structures were determined by spectroscopy, including 2D-NMR.     

Inhibition of thermal induced protein denaturation of extract/fractions of Withania somnifera and isolated withanolides

This study describes the in vitro inhibition of protein denaturation of extract/fractions of Withania somnifera and isolated withanolides including 20β hydroxy-1-oxo(22R)-witha-2,5,24 trienolide (1), (20R,22R-14α,20α)-dihydroxy-1-oxowitha-2,5,16,24 tetraenolide (2). The results showed that the extract/fractions of the plant evoked profound inhibitory effect on thermal-induced protein denaturation. The chloroform fraction caused the most dominant attenuation of 68% at 500 μg/mL. The bioactivity-guided isolation from chloroform fraction led to the isolation of compounds 1 and 2 that showed profound protein inhibition with 78.05% and 80.43% effect at 500 μg/mL and thus strongly complimented the activity of extract/fractions. In conclusion, extract/fractions of W. somnifera possessed strong inhibition of protein denaturation that can be attributed to these isolated withanolides.     

Two new withanolide lactones from flos daturae

Chemical investigation of the 50% ethanol eluate fraction from a macroporous resin of flowers of Datura metel L. collected in the Jiangsu Province of China resulted in the isolation of two new withanolides, baimantuoluoline G (1) and baimantuoluoside H (2). Their structures were elucidated as (12β,6β,22R)-1,10-seco-6,12,27-trihydroxy-26-oxo-witha-3,5,24-trienolide-1-oic acid-ε-lactone (1) and (5β,6α,12β,22R)-5,6,12,27-tetra-hydroxy-1,26-dioxo-witha-2,24-dienolide-27-O-β-glucopyranoside (2) on the basis of extensive spectroscopic analysis (1D, 2D-NMR and HRESIMS) and chemical studies.     

Three New Dammarane Glycosides from Gynostemma pentaphyllum

Three new dammarane-type glycosides (1-3) had been isolated from the aerial part of Gynostemma pentaphyllum (Thunb) Makino. The structures of compounds 1-3 had been elucidated as 3β, 12β, 25-trihydroxy-20(S), 24(S)-epoxydammarane 3-O-β-D-glucopyranosyl (1→2)-β-D-xylo-pyranoside, 3β, 12β, 25-trihydroxy-20(S), 24(R)-epoxydammarane 3-O-β-D-glucopyranosyl(1→2)-β-D-xylopyranoside and 3β, 12β, 23β, 25-tetrahydroxy-20(S), 24(S)-epoxydammarane3-O-β-D-glucopyranosyl (1→2)-β-D-xylopyranoside, respectively, on the basis of chemical and spectro -scopic methods.     

Microbial transformation of cortisol and prolyl endopeptidase inhibitory activity of its transformed products

Incubation of cortisol (1) with Gibberella fujikuruoi for 12 days yielded an oxidatively cleaved product, 11beta-hydroxyandrost-4-en-3,17-dione (2), while incubation with Bacillus subtilis and Rhizopus stolonifer yielded the reduced product, 11beta, 17alpha,20,21-tetrahydroxy-(20S)-pregn-4-en-3-one (3). Other reduced products, 11beta, 17alpha, 21-trihydroxy-5alpha-pregnan-3, 20-dione (4) and 3beta, 11beta, 17alpha, 21-tetrahydroxy-5alpha-pregnan-20-one (5) were obtained by incubation of compound 1 with Bacillus cerus. The inhibitory activity of compounds 1-5 against prolyl endopeptidase enzyme (PEP) was also assayed. Compounds 2 (IC50 162.8 microM) and 4 (IC50 157 microM) have shown significant inhibitory activity against PEP.     

Xanthones with antiproliferative effects on prostate cancer cells from the stem bark of Garcinia xanthochymus

Investigations of the constituents of the stem barks of Garcinia xanthochymus have yielded two new compounds, garcinenones X (1) and Y (2), along with five known xanthones, 1,4,5,6-tetrahydroxy-7-(3-methylbut-2-enyl)xanthone (3), 1,4,6-trihydroxy-5-methoxy-7-(3-methylbut-2-enyl)xanthone (4), 1,4,5,6-tetrahydroxy-7,8-di(3-methylbut-2-enyl)xanthone (5), 1,3,5,6-tetrahydroxy-4,7,8-tri(3-methylbut-2-enyl)xanthone (6), and 1,5,6-trihydroxy-7,8-di(3-methylbut-2-enyl)-6',6'dimethylpyrano(2',3':3,4)xanthone (7). The structures of the compounds were determined by spectroscopic methods. The cell growth inhibitory activity of the isolated compounds against the PC-3 cell line was measured. Among them, compounds 2, 3, 5, and 6 exhibited significant inhibitory effects with IG50 values of 14.3, 15.5, 11.1, and 6.8 microM, respectively.     

Six new dammarane-type triterpene saponins from the leaves of Panax ginseng

Six new minor saponins, together with known ginsenosides, were isolated from the leaves of Panax ginseng. The new saponins were named as ginsenoside-Rh5, -Rh6, -Rh7 -Rh8, -Rh9 and -Rg7, and their structures were elucidated on the basis of chemical and physicochemical evidence to be as follows: ginsenoside-Rh5: 3beta,6alpha,12beta,24zeta-tetrahydroxy-dammar-20(22),25-diene 6-O-beta-D-glucopyranoside (1), -Rh6: 3beta,6alpha12beta,20(S)-tetrahydroxy-25-hydroperoxy-dammar-23-ene 20-O-beta-D-glucopyranoside (2), -Rh7: 3beta,7beta,12beta,20(S)-tetrahydroxy-dammar-5,24-diene 20-O-beta-D-glucopyranoside (3), -Rh8: 3beta,6alpha,20(S)-trihydroxy-dammar-24-ene-12-one 20-O-beta-D-glucopyranoside (4), -Rh9: 3beta,6alpha,20(S)-trihydroxy-12beta,23-epoxy-dammar-24-ene 20-O-beta-D-glucopyranoside (5) and -Rg7: 3-O-beta-D-glucopyranosyl 3beta,12beta,20(S),24(R)-tetrahydroxy-dammar-25-ene 20-O-beta-D-glucopyranoside (6).     

Withangulatin I, a new cytotoxic withanolide from Physalis angulata

A new withanolide, withangulatin I (2), was isolated from the whole plant of Physalis angulata. Its structure was established as (20S,22R)-15alpha-acetoxy-5beta,6beta-epoxy-14alpha-hydroxy-1,4-dioxo-witha-2,16,24-trienolide on the basis of chemical and spectroscopic methods including 2D-NMR and circular dichroism (CD) experiments. Withangulatin A (1) and withangulatin I (2) were tested for their cytotoxic activities against two human cancer cell lines, colorectal carcinoma COLO 205 and gastric carcinoma AGS, in vitro. Compounds 1 and 2 exhibited inhibitory activities against these two human cancer cells with IC(50) values of 16.6 and 1.8 and 53.6 and 65.4 muM, respectively.     

Rhizophorin A, a novel secolabdane diterpenoid from the Indian mangrove plant Rhizophora mucronata

The ethyl acetate extract of Rhizophora mucronata furnished rhizophorin A, a novel secolabdane diterpenoid, (6R,11S,13S)-6,11,13-trihydroxy-2,3-seco-14-labden-2,8-olide-3-oic acid (1).     

Triterpenes from the spores of Ganoderma lucidum and their cytotoxicity against meth-A and LLC tumor cells

Six new highly oxygenated lanostane-type triterpenes, called ganoderic acid gamma (1), ganoderic acid delta (2), ganoderic acid epsilon (3), ganoderic acid zeta (4), ganoderic acid eta (5) and ganoderic acid theta (6), were isolated from the spores of Ganoderma lucidum, together with known ganolucidic acid D (7) and ganoderic acid C2 (8). Their structures of the new triterpenes were determined as (23S)-7beta,15alpha,23-trihydroxy-3,11-dioxolanosta-8, 24(E)-diene-26-oic acid (1), (23S)-7alpha,15alpha23-trihydroxy-3,11-dioxolanosta-8, 24(E)-diene-26-oic acid (2), (23S)-3beta3,7beta, 23-trihydroxy-11,15-dioxolanosta-8,24(E)-diene-26-oic acid (3), (23S)-3beta,23-dihydroxy-7,11,15-trioxolanosta-8, 24(E)-diene-26-oic acid (4), (23S)-3beta,7beta,12beta,23-tetrahydroxy-11,15-dioxolanos ta-8,24(E)-diene-26-oic acid (5) and (23S)-3beta,12beta23-trihydroxy-7,11,15-trioxolanosta-8,24(E )-diene-26-oic acid (6), respectively, by chemical and spectroscopic means, which included the determination of a chiral center in the side chain by a modification of Mosher's method. The cytotoxicity of the compounds isolated from the Ganoderma spores was carried out in vitro against Meth-A and LLC tumor cell lines.     

冬凌草中的新对映-贝壳杉烷二萜化合物

对河南省济源地区产冬凌草[Isodon rubescens(Hemsl.)Hara]再次进行了深入 的研究，从其叶的乙酸乙酯提取物中分离得到了16个化合物，其中1和2为两个新的 7，20-环氧-对映-贝壳杉烷类二萜化合物，其结构通过波谱分析确定为16（S）-羟 甲基-1α，6β，7β，11β-甲羟基-7α，20-环氧-对映-贝壳杉烷-15-酮（1）和 16（R）-羟甲基-1α，6β，7β，14β-四羟基-7α，20-环氧-对映-贝壳杉烷-15- 酮（2），分别命名为冬凌草已素（1）和庚素（2）；其余的已知化合物分别鉴定 为lasiodonin（3），冬凌草甲素（oridonin，4），乙素（ponicidin），丙素（ rubescensin C），丁素（rubescensin D），牛尾草丙素（rabdoternin C），荛 花香茶菜乙素（wikstroemioidin B），enmenol-1α-O-β-D-glucoside， enmenol，胡麻素（pedalitin），水杨酸，乌索酸，β-谷甾醇和胡萝卜甙。     

Withasteroids ofPhysalis. V. A study of the1H and13C NMR spectra of the withasteroids visconolide and 28-hydroxywithaperuvin C

The PMR and¹³C NMR spectra of new withasteroids — visconolide and 28-hydroxywithaperuvin C, isolated fromPhysalis viscosa L. — have been investigated. A detailed analysis of the spectral characteristics obtained is given. For visconolide is proposed the structure of 4β,12α,17β,28-pentahydroxy-1-oxo-5β, 6β-epoxy-22R-witha-2,24-dienolide, and for 28-hydroxywithaperuvin C that of 6β,14α,17β,20R, 28-pentahydroxy-l-oxo-22R-witha-2, 4, 24-trienolide.     

Three new cycloartane triterpene glycosides from Souliea vaginata

Three new cycloartane triterpene glycosides, soulieosides A (1), B (2), and C (3), were isolated from the rhizomes of Souliea vaginata, and their structures were elucidated on the basis of extensive NMR experiments and chemical methods. Soulieosides A-C were assigned as 25-O-acetylcimigenol-3-O-beta-D-(2-acetyl)xylopyranoside (1), 24-O-acetyl-isodahurinol-3-O-beta-D-(2-acetyl)xylopyranoside (2) and 20(S),22(R),23(S),24(R)-16beta:23;22:25-diepoxy-3beta,23,24-trihydroxy-9,19-cyclolanostane-3-O-beta-D-(4-acetyl)xylopyranoside (3), respectively.     

Reaction of grayanotoxin-II with thallium (III) nitrate

Reaction of grayanotoxin-II (1) with thallium nitrate gave 3(S), 20-epoxy-6 (S), 14 (R), 16 (R)-trihydroxy-5-oxo-5, 10-seco-ent-kaur-1 (10) -ene (2). The structure of 2 was elucidated by the X-ray diffraction analysis of its reduction product (3).     

Alkaloide aus Cortex Condurango

From the CH₂Cl₂ extract of the bark of Marsdenia cundurango Reichenb. fil. (Cortex Condurango) a mixture of basic compounds could be isolated. Repeated thin layer and column chromatography yealded two alkaloids in pure form. For Kondurangamin A, which would be the mayor alkaloid with a content of 0.0007%, the structure was determined as 3β, 14β,20-trihydroxy-11 α-nicotinoyloxy-12β-acetoxy-5α,14β-pregnane and for Kondurangamin B as 3β,11α,12β,14β-tetrahydroxy-20-nicotinoyloxy-5α,14β-pregnane.