Two Novel Saponins from Lysimachia capillipes

We have isolated some flavones, lactone and two new saponins from Lysimachia capillipes1-3, now we continue to report the isolation and structural elucidation of two novel saponins, capilliposide C 1 and capilliposide D 2. Capilliposide C showed significant cytotoxic activity against human A2780 cells. The whole plant of Lysimachia capillipes was extracted with 95% and 50% EtOH, successively, and the extracts were combined and concentrated. The residue was chromatographed on silica gel res…     

(±)-Cryptamides A–D,Four Pairs of Novel Dopamine Enantiomer Trimers from the Periostracum Cicadae

Four pairs of novel dopamine enantiomer trimers, (±)-cryptamides A–D (1–4), and 10 pairs of previously described dopamine enantiomer dimers (5–14) were isolated from the Periostracum cicadae, the cast-off shell of the insect Cryptotympana pustulata. Aside from being pairs of enantiomers, the eight trimers were also elucidated to be regioisomers, most likely resulting from their mechanism of formation, [4 + 2] cycloaddition. The discovery of dopamine trimers is rarely reported when it comes to natural products derived from insects.     

Oligostilbenoids from Dipterocarpaceaeous Plants: A New Resveratrol Tetramer from Vateria indica and the Revised Structure of Isohopeaphenol

The investigation of phenolic constituents in Vateria indica afforded five resveratrol tetramers, vateriaphenols B and C, isohopeaphenol, hopeaphenol, and shoreaketone. Their structures and configurations were established by spectroscopic methods. The structure assigned to vateriaphenol C was found to be identical with the structure reported in the literature for the resveratrol tetramer isohopeaphenol. The structure of isohopeaphenol was revised and confirmed by spectroscopic evidences.     

Absolute Configuration of Resveratrol Oligomers Isolated from Hopea utilis

Phytochemical studies on a stem of Hopea utilis (Dipterocarpaceae) resulted in the isolation of two new resveratrol derivatives, namely hopeaside E ( 1 ; resveratrol trimer) and hopeaside F ( 2 ; resveratrol pentamer), together with ten known resveratrol derivatives, 3 – 12 . The structures of the new compounds were elucidated by spectroscopic analyses, including NMR experiments, and their absolute configurations were determined on the basis of a comparative configurational analysis using the β‐D ‐glucopyranosyl group and chiroptical data. The absolute configuration of (+)‐balanocarpol ( 3 ) was also determined by acid‐catalyzed skeletal conversion.     

Two New Oleanane Saponins from Anemone anhuiensis

Two new oleanane triterpene saponins, named as anhuienside C (1) and D (2), were isolated from the rhizomes of Anemone anhuiensis (Ranunculaceae). The structures of the new compounds were elucidated as 3-O-α-L-rhamnopyranosyl (1→ 2)-β -D-xylopyranosyl oleanolic acid 28-O-b -D-glucopyranosyl (1→ 6)-b -D-glucopyranosyl ester (1) and 3-O-β-D-xylopyranosyl oleanolic acid 28-O-α-L-rhamnopyranosyl (1→ 4)-β-D-glucopyranosyl (1→6)-β-D-gluco-pyranosyl ester (2), respectively.     

Metabolites with a Novel C30 Backbone from Marine Ciliates

Challenging questions are raised about the biosynthetic origin of vannusal A ( 1 ), a metabolite that is isolated from the tropical marine ciliate Euplotes vannus and contains an unusual C₃₀ backbone.     

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.     

Two Novel Nortriterpenoids from Gomphostemma parviflorum

Two new nortriterpenoids, gomphoparvin A ( 1 ) and B ( 2 ), together with five known compounds, were isolated from the AcOEt‐soluble MeOH extract of Gomphostemma parviflorum (whole plant). Their structures and relative configurations were elucidated mainly on the basis of 1D‐ and 2D‐NMR as well as MS analyses.     

Indole-substituted 2,4-diamino-5,8-dihydropyrido[2,3-d]pyrimidines from one-pot process and evaluation of their ability to bind dopamine receptors

A series of novel 7-indole substituted 2,4-diamino-5,8-dihydropyrido[2,3-d]pyrimidine analogous to the 2,4-diaminopteridine core were synthesized by the three-component one-pot cyclocondensation between 2,4,6-triaminopyrimidine, 3-(2-cyanoacetyl)indole and aromatic aldehydes. The reactions, which exhibited good performance, proceeded in EtOH using indium (III) chloride as catalyst under microwave irradiation, in short reaction times. On the basis of certain structural similarity of these compounds with known ligands of the D2 dopamine receptors (D2DR), the study of these compounds as possible ligands of dopamine D2 and D1 receptors was carried out. Three of them showed moderate affinity to D2-DR since the Ki D1/D2 ratio reached values of 40, 65 and 31 for compounds 4c, 4k and 4j, respectively. Finally, molecular modeling studies revealed stronger molecular interactions of such derivatives with the D2DR than with D1DR, what agrees with the experimental data, and gives an additional support to the observed selectivity to the D2DR.     

Four Novel Diterpenoids from Crinipellis sp. 113

Four novel diterpenoids, namely (4β)‐4,4‐O‐dihydrocrinipellin A ( 1 ), (4β,8α)‐4,4‐O,8,8‐O‐tetrahydrocrinipellin B ( 2 ), crinipellin C ( 3 ), and crinipellin D ( 4 ), along with three known ones, (3β,4β)‐3,3‐C,4,4‐O‐tetrahydrocrinipellin A ( 5 ), (4β)‐4,4‐O‐dihydrocrinipellin B ( 6 ), and phlebiakauranol alcohol, were isolated from the fungal strain Crinipellis sp. 113. Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and by HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays with the novel compounds 1 – 4 were carried out, showing moderate activities against HeLa cells and no effects on the growth of tested bacteria or yeast.     

Two Novel Sesquiterpene Diglycosides from Dictamnus dasycarpus

TherootbarkofDicla));nuscl(I311'c'(I)pllsTurcz.(Chinesename"Bai-Xian-Pi")(Rutaceae)isatraditi0nalChinesemedicineusedtbrtreatment0fjaundice,coughandrheumatism.lthasaIs0beenwidelyusedt0treatsomeskindiseases1.lnourpreviouspapers.werep0rtedtl1eisolati0nandstructuredeterminati0n0fantifungalfuroquinolinealkal0idsandfivenovelsesquiterPeneglycosides=".Inac0ntinuati0n0fourinvestigationofchemicalco11sitituents0fthisplant,weidentifiedan0thertw0novelsesquiterpenediglycosidesnameddictamn0sidesFlandG2f…     

Two Novel Poly-Oxygen Bipyridine Alkaloids from Speranskia tuberculata

In a previous paper' we reported two optically active pyridine-2, 6 (l H. 3H)-dionealkatoids speranskalines A and B from SPeranskia luberculala (Bge.) (Euphorbiaceae)We report here the isolation and structural elucidation of two novel poly-oxygenbipyridine alkaloids named speranculatines A (l) and B (2) from this plant.The acetone (or methanol) extract of the air-dried whole plants of .q. IllhelT.lllaluwas subjected to column chromatography on St gel to afford a fraction. whichdemonstrate…     

Two Novel Antioxidative Stilbene Tetramers from Parthenocissus laetevirens

Laetevirenols F ( 1 ) and G ( 2 ), two novel stilbene tetramers with an unprecedented skeleton, were isolated from Parthenocissus laetevirens. Their structures were elucidated by spectroscopic analysis, including 1D‐ and 2D‐NMR experiments, and their possible biogenetic pathway was discussed. In addition, both compounds were determined to be potent singlet‐oxygen quenchers by electron paramagnetic resonance (EPR) experiments, which highlights their potential pharmacological applications in singlet oxygen mediated diseases.     

Two New Iridoids from the Roots of Valeriana officinalis

Valeriana officinalis is the official species used in Europe as sedatives and tranquilizers for centuries. Two new iridoids, volvaltrates C and D ( 1 and 2 ) were isolated from the ethanol extract as a mixture from the roots of V. officinalis. Their structures were elucidated by spectroscopic evidence including MS, 1D and 2D‐NMR spectra.     

Two New Diterpenoids from Hedychium forrestii

Two new labdane diterpenes isolated from the rhizomes of Hedychium forrestii were determined by spectroscopic evidence to be labda-8(17), 11, 13-trien-7β-hydroxyl- 15(16)-olide (1,hedyforrestin B) and labda-8(17), 11, 13-trien-7β,16-dihydroxyl-16(15)-olide (2, hedyforrestinC).     

Two New Xanthone Glycosides from Securidaca inappendiculata

Securidaca inappendiculata Hassk. is liana which distributed in the south of China. It is used in Guangxi folk medicine for the treatment of rheumatalgia, enterogastritis and inflammatory disease1. We report here the structure elucidation of two new xanthone glycosides, 3-O-b-D-gluco-pyranosyl-1,7-dihydroxy-2-methoxyxanthone (1) and 6-O-b- D-glucopyranosyl-1-hydroxy-4,7-dimethoxyxanthone (2), isolated from the stems of S. inappendiculata. OOOHOOHOCH3bDGlcAB 1 Compound 1 was obtai…     

Two New Sesquiterpenes from the Resin of Toxicodendron vernicifluum

A phytochemical investigation of the resin of Toxicodendron vernicifluum resulted in the isolation of two new sesquiterpenoids, toxicodenanes D ( 1 ), endowed with a new carbon skeleton, and E ( 2 ), along with six known sesquiterpenoids (Fig. 1). Their structures were determined by spectroscopic analysis, including 1D‐ and 2D‐NMR and mass spectrometry.     

Two Novel Neophysalins from Physalis alkekengi L. var. franchetii

Two novel neophysalins, named physalin W ( 1 ) and physalin X ( 2 ), were isolated from the EtOH extract of the aerial parts of Physalis alkekengi L. var. franchetii (Solanaceae). Their structures were determined mainly by spectroscopic techniques including 2D‐NMR (HMBC, HSQC, ¹H,¹H‐COSY, NOESY) and MS experiments.