Three new C_(21) steroidal glycosides from the roots of Cynanchum inamoenum

Three new C21 steroidal glycosides named inamoside E （1）, inamoside F （2） and inamoside G （3） were isolated from the roots of Cynanchum inamoenum （Maxim.） Loes. Their structures were determined by spectroscopic analysis, especially by ID and 2D NMR experiments.

Saponins-rich fraction of Calotropis procera leaves elicit no antitrypanosomal activityin a rat model

Objective:To examine thein vitroandin vivoanti-Trypanosoma evansi(T.evansi)activity ofsaponins-rich fraction ofCalotropis procera(cpsf)leaves as well as the effect of the fraction onthe parasite-induced anemia.Methods:A 60-minutes time course experiment was conductedwith various concentrations of the fraction using a 96-well microtiter plate technique,andsubsequently used to treat experimentallyT.evansiinfected rats at 100 and 200 mg/kg bodyweight.Index of anemia was analyzed in all animals during the experiment.Results:The cpsfdid not demonstrate anin vitroantitrypanosomal activity.Further,the cpsf treatments did notsignificantly(P>0.05)keep the parasites lower than the infected untreated groups.At the end ofthe experiment,allT.evansiinfected rats developed anemia whose severity was not significantly(P>0.05)ameliorated by the cpsf treatment.Conclusions:It was concluded that saponins derivedfromCalotropis proceraleaves could not elicitin vitroandin vivoactivities againstT.evansi.

Insignin A, A Novel C_21-Steroidal Aglycone from Biondia insignis

Insignin A, a new C21-steroidal aglycone having the rare 15,16-seco pregnane skeleton was isolated from the acidic hydrolysis part of the 95% EtOH extract of Biondia insignis. It's structure was identified to be 15R,16-epoxy-3?,14?,16?-trihydroxy-15,16-secopregn-5-ene-20-one based on the spectral data.

Floristic Account of the Asclepiadaceous Species from the Flora of Dera Ismail Khan District, KPK, Pakistan

In the present study an account is given of an investigation based on the results of the floristic research work conducted between 2005 and 2007 in Dera Ismail Khan District, north western Pakistan. The area was surveyed and 8 Asclepi- adaceous plant species were collected. These plant species are Calotropis procera (Aiton) W. T. Aiton. Caralluma edulis (Edgew.) Benth., Leptadenia pyrotecnica (Forssk.) Decne., Oxystelma esculentum (L. f.) R. Br., Pentatropis nivalis (J. F. Gmel.) D. V. Field & J. R. I. Wood, Pergularia daemia (Forssk.) Blatt.& McCann., Periploca aphylla Decne. and Stapelia gigantea N.E.Br. The study showed that five plants were used ethnobotanically in the area. All the plants were deposited as voucher specimens in the Department of plant sciences, Quaid-i-Azam University, Islamabad, for future references. Complete macro & microscopic detailed morphological features of the species have been discussed. Taxo- nomic key was developed to differentiate closely related taxa.

Recent advances in phytochemistry and pharmacology of C_(21) steroid constituents from Cynanchum plants

Cynanchum is one of the most important genera in Asclepiadaceae family, which has long been known for its therapeutic effects. In this genus, 16 species are of high medicinal value. The extracts of the root and/or rhizome parts have been applied in traditional Chinese medicines(TCM) for the prevention and treatment of various illnesses for centuries. C21 steroids, as the typical constituents of Cynanchum species, possess a variety of structures and pharmacological activities. This review summarizes the comprehensive information on phytochemistry and pharmacology of C21 steroid constituents from Cynanchum plants, based on reports published between 2007 and 2015. Our aim is to provide a rationale for their therapeutic application, and to discuss the future trends in research and development of these compounds. A total of 172 newly identified compounds are reviewed according to their structural classifications. Their in vitro and in vivo pharmacological studies are also reviewed and discussed, focusing on antitumor, antidepressant, antifungal, antitaging, Na+/K+-ATPase inhibitory, appetite suppressing and antiviral activities. Future research efforts should concentrate on in vitro and in vivo biological studies and structure activity relationship of various C21 steroid constituents.

Two New C-21 Steroidal Glycosides from the Stems of Stephanotis mucronata

Two new C-21 steroidal glycosides, mucronatosides M（1） and N（2）, were isolated from the stems of Stephanotis mucronata, together with one known compound stephanoside M（3）. On the basis of chemical evidence and extensive spectroscopic methods, including one-dimensional and two-dimensional NMR, the structures of the two new compounds were identified as 12-O-tigloyl-20-O-N-methylanthraniloyl sarcoslin 3-O-β-D-glucopyranosyl-（1→4）-6- deoxy-3-O-methyl-β-D-allopyranosyl-（→4）-β-D-cymaropyranosyl-（1→4）-β-D-cymaropyranoside （1）, and 12-O- cinnamoyl-20-O-nicotinoyl（ 2OS）-pregn-6-ene-3 β,5α,8βm12 β,14β,17β,20-heptanol 3-O-β-D-glucopyranosyl-（1→4）-6- deoxy-3-O-methyl-β-D-allopyranosyl-（1→4）-β-D-cymaropyranosyl-（1→4）-β-D-cymaropyranoside （2）.

Three New C_(21) Steroidal Glycosides from Roots of Cynanchum otophyllum

Objective To investigate the chemical structures of glycosides in the roots of Cynanchum otophyllum（Asclepiadaceae） and to find new glycosides. Methods The total glycosides in the roots of C. olophyllum were separated by silica gel column chromatography. The structures of the resulting compounds were determined by NMR and FAB-MS spectra. Results Three C21 steroidal glycosides were separated. Their structures were determined as caudatin 3-O-（4-O-methyl-β-D-cymaropyranosyl）-（1→4）-ɑ-D-oleandropyranosyl-（1→4）-β-D-glucopyranosyl-（1→4）-ɑ-L-rhamnopyranoside（1）, caudatin 3-O-β-D-digitoxopyranosyl-（1→4）-ɑ-D-oleandropyranosyl-（1→4）-β-Ddiginopyranosyl-（1→4）-β-D-glucopyranoside（2）, and caudatin 3-O-β-D-diginopyranosyl-（1→4）-ɑ-D-oleandropyranosyl-（1→4）-ɑ-D-oleandropyranosyl-（1→4）-β-Dglucopyranoside（3）, respectively. Conclusion Glycosides 1-3 are new compounds.

C_(21) Steroidal Glycosides from Acidic Hydrolysate of Cynanchum otophyllum

Objective To investigate the structures of compounds in the rhizome of Cynanchum otophyllum（Asclepiadaceae）, and to find new C21 steroidal glycosides. Methods The ethyl acetate extract from the rhizome was subjected to acidic hydrolysis and isolated by column chromatography; The structures of the purified compounds were determined by spectral methods. Literature search confirmed whether those compounds were of new structures. Results Three compounds were isolated and their structures were deacetylmetaplexigenin 3-O-β-D-oleandropyranosyl-（1→4）-α-D-oleandropyranosyl-（1→4）-α-D-oleandropyranoside（1）, deacetylmetaplexigenin 3-O-α-D-oleandropyranosyl-（1→4）-β-D-thevetopyranosyl-（1→4）-α-D-oleandropyranoside（2）, and deacetylmeta-plexigenin 3-O-β-D-cymaropyranosyl-（1→4）-α-D-oleandropyranoside（3）, respectively. Conclusion Compounds 1-3 are new compounds.

C_(21) Steroidal Saponins from Cynanchum otophyllum

Objective To study the chemical structures of saponins in the rhizome of Cynanchum otophyllum（Asclepiadaceae）, and to find new compounds. Methods The total saponins of the rhizome were separated by silica gel column chromatography. The chemical structures of obtained compounds were determined by NMR and FAB-MS spectra. Results Three C21 steroidal saponins were separated. Their structures were determined as caudatin 3- O-β-D-glucopyranosyl-（1 →4）-β- D-digitoxopyranosyl-（1 → 4）-β-D-digino- pyranosyl-（1 -4）-α-D-oleandropyranoside （1）, caudatin 3-O-β-D-oleandropyranosyl- （1→4）-α-D-oleandropyranosyl-（1→4）-α-D-oleandropyranoside （2）, and caudatin 3-O- β-D-glucopyranosyl-（1 →4）-α-D-oleandropyranosyl-（1 -4）-β-D-diginopyranosyl-（1→4）- α-D-oleandropyranoside （3）, respectively. Conclusion Saponins 1-3 are new compounds.