Two New Steroidal Glycosides from Fermented Leaves of Agave americana

Two new spirostanol glycosides named agamenoside A and B, ere isolated from the fermented leaves of Agave americana. Their structures were elucidated as (23S,25R)-5α-spirostan-3β,6α，23－triol 3-O-α-L-rhamnopyranosyl-(1→3)-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside(1) and (25R)-5α-spiro-stan-3β,6α-diol 3-O-β-D-glucopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyra-nosyl-(1→4)-β-D-galactopyranoside(2) by a combination of chemical and spectral methods.     

A New Pregnane Glycoside from Fermented Leaves of Agave americana

A new minor pregane glycoside was isolated from the fermented leaves of Agave americana.Its structure was elucidated as (20S)-5α-pregnane-3β，20-diol 20-O-β-D-glucopyrano-side(1)by spectral methods.     

Two New Steroidal Saponins from the Fresh Leaves of Agave sisalana

A new furostanol saponin, sisalasaponin C ( 1 ), and a new spirostanol saponin, sisalasaponin D ( 2 ), were isolated from the fresh leaves of Agave sisalana, along with three other known steroidal saponins and two stilbenes. Their structures were identified as (3β,5α,6α,22α,25R)‐3,26‐bis[(β‐D ‐glucopyrano‐ syl)oxy]‐22‐hydroxyfurostan‐6‐yl β‐D ‐glucopyranoside ( 1 ), (3β,5α,25R)‐12‐oxospirostan‐3‐yl 6‐deoxy‐α‐L ‐mannopyranosyl‐(1→4)‐β‐D ‐glucopyranosyl‐(1→3)‐[β‐D ‐xylopyranosyl‐(1→3)‐β‐D ‐glucopyranosyl‐(1→2)]‐β‐D ‐glucopyranosyl‐(1→4)‐β‐D ‐galactopyranoside ( 2 ), (3β,5α,6α,22α,25R)‐22‐methoxyfurostane‐3,6,26‐triyl tris‐β‐D ‐glucopyranoside, cantalasaponin‐1, polianthoside D, (E)‐ and (Z)‐2,3,4′,5‐tetrahydroxystilbene 2‐O‐β‐D ‐glucopyranosides. The last three known compounds were isolated from the fresh leaves of Agavaceae for the first time. The structures of the new compounds were elucidated by detailed spectroscopic analysis, including 1D‐ and 2D‐NMR experiments, and chemical techniques.     

Spirostanol Sapogenins and Saponins from Convallaria majalis L. Structural Characterization by 2D NMR,Theoretical GIAO DFT Calculations and Molecular Modeling

Two new spirostanol sapogenins (5β-spirost-25(27)-en-1β,2β,3β,5β-tetrol 3 and its 25,27-dihydro derivative, (25S)-spirostan-1β,2β,3β,5β-tetrol 4) and four new saponins were isolated from the roots and rhizomes of Convallaria majalis L. together with known sapogenins (isolated from Liliaceae): 5β-spirost-25(27)-en-1β,3β-diol 1, (25S)-spirostan-1β,3β-diol 2, 5β-spirost-25(27)-en-1β,3β,4β,5β-tetrol 5, (25S)-spirostan-1β,3β,4β,5β-tetrol 6, 5β-spirost-25(27)-en-1β,2β,3β,4β,5β-pentol 7 and (25S)-spirostan-1β,2β,3β,4β,5β-pentol 8. New steroidal saponins were found to be pentahydroxy 5-O-glycosides; 5β-spirost-25(27)-en-1β,2β,3β,4β,5β-pentol 5-O-β-galactopyranoside 9, 5β-spirost-25(27)-en-1β,2β,3β,4β,5β-pentol 5-O-β-arabinonoside 11, 5β-(25S)-spirostan-1β,2β,3β,4β,5β-pentol 5-O-galactoside 10 and 5β-(25S)-spirostan-1β,2β,3β,4β,5β-pentol 5-O-arabinoside 12 were isolated for the first time. The structures of those compounds were determined by NMR spectroscopy, including 2D COSY, HMBC, HSQC, NOESY, ROESY experiments, theoretical calculations of shielding constants by GIAO DFT, and mass spectrometry (FAB/LSI HR MS). An attempt was made to test biological activity, particularly as potential chemotherapeutic agents, using in silico methods. A set of 12 compounds was docked to the PDB structures of HER2 receptor and tubulin. The results indicated that diols have a higher affinity to the analyzed targets than tetrols and pentols. Two compounds (25S)-spirosten-1β,3β-diol 1 and 5β-spirost-25(27)-en-1β,2β,3β,4β,5β-pentol 5-O-galactoside 9 were selected for further evaluation of biological activity.     

A New Spirostanol Saponin from Dioscorea futshauensis

A new screening bioassay detecting deformation of mycelia germinated from conidia of Pyricularia oryzae P-2b was first developed for quantitative application to screen antifungal and antineoplastic agents by H. Kobayashi1,2. We have introduced and applied this bioassay in the search of bioactive agents from Traditional Chinese Medicine3,4. The ethanol extract of Dioscorea futshauensis R. Kunth (Dioscoreaceae) showed a strong activity against the growth of Pyricularia oryzae P-2b. Its buta…     

Two New Steroidal Saponins from Tacca plantaginea

Two new C27 steroidal glycosides, named taccaoside A(1) and B(2), were isolated from the traditional Chinese herb Tacca plantaginea. The spectroscopic and chemical evidences revealed their structures to be 26-O-β-D-glucopyranosyl-(25R)-3β,26-dihydroxy furost-5,20-diene-3-O-[α-L-rhamnopyranosyl(1→2)]-[α-L-rhamnopyranosyl(1→3)]-β-D-glucopyranoside(1) and 26-O-β-D-glucopyranosyl-(25R)-3β,26-dihydroxy furost-5,20-diene-3-O-[α-L-rhamnopyranosyl-(1→2)]-[β-D-glucopyranosyl(1→3)-α-L-rhamnopyranosyl(1→3)]-β-D-glucopyranoside(2),respectively.     

Two New Steroidal Glycosides from Ophiopogon japonicus

The tuber of Ophiopogon japonicus Ker-Gawl. is recorded to have various functions, such as against cardiovascular diseases and anti-bacteria, and used as a potent drug to treat different diseases, especially heart diseases1. Since the first steriodal glycoside was isolated from the plant by Japanese scholars2, much attention has been paid to the studies of the chemical components of O. japonicus in recent decades. Steroidal glycosides as the major glycosides with the aglycones of ruscogenin …     

Densitometric Determination of Hecogenin from Agave americana Leaf Using HPTLC

We report a simple TLC densitometric method for the quantification of hecogenin from the leaves of Agave americana using HPTLC. The method was validated for precision, repeatability and accuracy. The method was found to be precise with RSD of 0.78 (intraday) and 0.82 (interday) for different concentrations of hecogenin. Instrumental precision was 0.42 (% RSD) for hecogenin. The content of hecogenin in different samples was estimated by the proposed method and was found to be in the range of 0.05−0.14% w/w in the samples analysed. Accuracy of the method was checked by conducting recovery study at three different levels for hecogenin and the average percentage recovery was 98.98%, 101.92% and 103.33%, respectively. The TLC densitometric method developed for the quantification of hecogenin was found to be simple, precise, specific, sensitive, accurate and can be used in routine quality control. Revised: 7 and 25 April 2006     

Two New Steroidal Glycosides from Liriope muscari

Liriope muscari (Decn.) Bailey (Liliaceae) is a folk medicinal plant used as a substitute of Ophiopogon japonicus (Thunb.) Ker-Gawl., mainly distributing in Quanzhou, Fujian Province, China1. Previously, we reported the isolation and identification of two…     

Two New Steroidal Glycosides from Caryopteris terniflora

Two new steroidal glycosides were isolated from the Chinese medicinal plant Caryopteris terniflora. The spectroscopic and chemical evidences revealed that their structures tobe 6-(β-sitosteroyl-3-O-β-glucopyranosidyl) hexacosanate 1 and 6‘-(stigmasteroyl-3-O-β-glucopy-ranosidyl) linolenate 2, respectively.     

Two New Steroidal Saponins from Diuranthera inarticulata

There are only three species in the genus Diuranthera (Liliaceae), which is endemic in the southwest of China1. Four steroidal saponins, diuranthosides A-C and chloromalo-side A were isolated from the fresh roots of D. major. This paper deals with the structure elucidation of two new steroidal saponins, diuranthosides D and E, which were isolated from the methanolic extract of whole plant of D. inarticulata Wang et K. Y. Lang.Diuranthoside D (1), [(]-38 (c 0.08, pyridine), afforded galac…     

Two New Furostanol Glycosides from Asparagus cochinchinensis

Two new furostanol oligoglycosides named as aspacochioside A(1)and B(2) were isolated from the roots of Asparagus cochinchinensis (Lour.)Merr..Their structures were clucidated to be 3-O-[{α-L-rhamnopyranosyl-(1→4）}{β-D-glucopyranosyl}]-26-O-[β-D-glucopy-ranosyl]-(25S)-5β-furostane-3β，22α，26-triol 1 and 3-O-[{α-L-rhamnopyranosyl-(1→4）}{β-D-glu-copyeransoyl}]-26-O-[β-D-glucopyranosyl]-22α-methoxy-(25S)-5β-furostane-3β，26-diol 2 on the basis of spectroscopic techniques and chemical methods.     

Two New Chromone Glycosides from Selaginella uncinata

Two new chromone glycosides,5-hydroxy-2,6,8-trimethylchromon-7-O-β-D-gluco-pyranoside,named uncinoside A;5-acetoxy-2,6,8-trimethylchromone-7-O-β-D-glucopyranoside, named uncinoside B,and a known chromone compound named 8-methyl eugenitol were isolated from Selaginella uncinate. Their structures were elucidated by spectra analysis of FAB-MS,1D NMR and 2D NMR including ^1H NMR,^13C NMR,HMQC,HMBC and single-crystal X-ray diffraction techniques.     

Two New Pyrrolizidines from Ligularia lankongensis

Two new pyrrolizidines named lankongensisine A (1), B (2) were isolated from the roots of Ligularia lankongensis collected in Lijiang, Yunnan, and their structures were established by spectroscopic analysis.     

Two New Natural Methoxyflavonoids from Leaves of Murraya paniculata(L.) Jack

Two new natural methoxyflavonoids and two known methoxyflavonoids were isolated from the ethanol fraction of the leaves of Murraya paniculata(L.) Jack. The two new natural methoxyflavonoids were elucidated as 2'-hydroxy-3,4,5,3',4',6'-hexamethoxychalcone(1) and 6,7,8,3',4'-pentamethoxyflavanone(2) on the basis of ¹³C NMR and mass spectra. The two known methoxyflavonoids were identified as 3'-hydroxy-5,7,4'-trimethoxyflavone(3) and 2'-hydroxy-3, 4, 4', 6'-tetramethoxychalcone(4).     

Three New C21 Steroidal Glycosides from the Roots of Cynanchum komarovii Al.Iljinski

Three new C21 steroidal glycosides named komaroside A, komaroside B, komaroside C were isolated from the ethanolic extract of the roots of Cynanchum komarovii Al.Iljinski(Asclepiadaceae), their structures were determined by physiochemical and spectroscopic analysis.     

南海短足软珊瑚Cladiella sp.中两个新孕甾醇苷的分离

从短足软珊瑚Cladiella sp．中,分离得到3个甾类化合物：孕甾-5,20-二烯-3β-醇-3-O-α-L-吡喃岩藻糖苷(1)、孕甾-5,20-二烯-3β-醇-3-O-β-D-吡喃木糖苷(2)和(22E,24R)-麦角甾-7,22-二烯-3β,5α,6β-三醇(3),其中1和2为新化合物．孕甾醇苷具有抗早孕和抑制肿瘤细胞生长活性．     

Two New ent—Kaurane Diterpenoids from Isodon japonica

Two new ent-kauranoids,named maoyecrystals A (1) and B(2),were isolated from the EtOAc extract of the dried leaves of Isodon japonica (Burman f.) Hara collected in Tongbai mountains ,Henan Province,Their structures were determined on the basis of spectral data,especially by 2D NMR.     

Two New C—21 Steroidal Glycosides from Cynanchum aurichulatum

Two new C-21 steroidal glycosides, cynanauriculoside I and cynanauriculoside Ⅱ, were isolated from the roots of Cynanchum aurichulatum. Their structures were established using spectroscopic methods including one and two-dimensional NMR.     

Two New Glycosides from the Roots of Ranunculus ternatus

Two new glycosides named as ternatoside A 1 and ternatoside B 2 were isolated from the roots of Ranunculus ternatus, the structures were determined by 1D and 2D NMR, ESI-MS techniques, and chemical methods.