Cohirsine - a novel isoquinolone alkaloid from

A novel alkaloid, cohirsine (1) was isolated from . Its structure has been investigated by extensive NMR studies including 2D NMR experiments. Its stereochemistry has been determined by 2D NOESY and NOE difference measurements.     

Trichocarpinine,a Novel Hetidine–Hetisine Type Bisditerpenoid Alkaloid from Aconitum tanguticum var. trichocarpum

Trichocarpinine ( 1 ), the first hetidine–hetisine type bisditerpenoid alkaloid, was isolated from the whole herbs of Aconitum tanguticum var. trichocarpum. Its structure was determined by a combination of spectroscopic techniques, including HR‐ESI‐MS and 1D‐ and 2D‐NMR experiments. Its plausible biogenetic pathway was proposed as well (Scheme).     

Schiglautone A, a new tricyclic triterpenoid with a unique 6/7/9-fused skeleton from the stems of Schisandra glaucescens

Schiglautone A (1), a unique 6/7/9-fused tricyclic carbon backbone triterpenoid, was isolated from the stems of Schisandra glaucescens. Its structure was determined on the basis of spectroscopic analysis and single-crystal X-ray crystallography. A hypothetical biosynthetic pathway of 1 was postulated.     

Triptowilfolide,a Novel Compound from Tripterygium wilfordii

A novel diterpenoid‐related compound, triptowilfolide ( 1 ), was isolated from the root bark of the Tripterygium wilfordii. Its structure was established by spectroscopic means.     

Hypertricone,a Constituent with a Novel Skeleton,Isolated from Hypericum geminiflorum

A novel compound containing an oxepane ring, hypertricone ( 1 ), was isolated from the leaves of Hypericum geminiflorum. Its structure, including the relative configuration, was elucidated from spectroscopic data and a computer‐generated plot for the 3D structure.     

Structure and synthesis of nectrisine, a new immunomodulator isolated from a fungus.

The structure of a novel immunomodulator, nectrisine (1), has been elucidated on the basis of chemical and spectroscopic evidence. Its absolute stereochemistry was predicted on the basis of the dibenzoate chirality rule and finally confirmed by a synthesis from D-glucose.     

Polystachyne F, a 5,10-seco-neoclerodane from Salvia polystachya

A new 5,10-seco-neoclerodane diterpene, polystachyne F (1), was isolated from the aerial parts of Salvia polystachya. Its structure was established on the basis of its spectroscopic properties and X-ray crystallographic analysis. Some correlations in the NOESY spectrum of 1 suggested the existence of a conformational equilibrium.     

A new flavonoid with a benzoic acid substituent from Selaginella uncinata

6-（5-Carboxyl-2-methoxyphenyl）-apigenin （1）, a new flavonoid, was isolated from the 60% ethanol extract of Selaginella uncinata （Desv.） Spring. Its structure was established by spectroscopic methods. Compound 1 represents the first example of the flavonoids possessing a benzoic acid substituent at C-6.     

Synthesis of a kind of geminal imidazolium ionic liquid with long aliphatic chains

A novel geminal imidazolium ionic liquid with long hydrocarbon group,1,4-bis(3-tetradecylimidazolium-1-yl)butane bromide was synthesized and an efficient synthesized method was introduced detailedly.Its structure was determined by FT-IR,~1H NMR and elemental analysis.     

The synthesis and fluorescence of a methoxy-phenyl substituted C_60-pyrrolidine derivative

A new 4-methoxyphenyl substituted C60-pyrrolidine derivative, C60(C10H13NO) (1), was prepared and its room-temperature fluorescence was studied. Its fluorescence intensity is three times stronger than that of C60. Its singlet energy was estimated to be 25 kJ/mol lower than that of C60. The fluorescence lifetime was determined to be 2.1+0.3 ns by using the frequency domain method. The fluorescence quenching by concentration and aromatic electron donor: N, N-dimethyl aniline (DMA) was investigated. Data show that its fluorescence could not be quenched by DMA.     

Erythrinarbine,a Novel nor-A ring Erythrina Alkaloid from Erythrina arborescens

ErythrinaarborescensRoxb.belongstoErythrinagenusofPapilionaceaefamilyplants,andiswidelydistributedintropicalandsubtropicalregionsoftheworld,aswellasinthesouthandsouth-westofChina'.AsaChinesefolkmedicine,itsrootandstemareusedtotreatrheumatismanddysentery'.TheErythrinaalkaloids,normallyaC.,tetracyclicspiroaminesystem,erythrinanel,arethecharacteristicconstituentsinErylhrinagenusandabout100erythrinaalkaloidshavebeensofarreportedfromthisgenusplants'-'.MostoftheseErythrinaalkaloidshaveatetrahydr…     

Marruboside,a new phenylethanoid glycoside from Marrubium vulgare L

A new phenylethanoid glycoside, marruboside, has been isolated from the aerial parts of Marrubium vulgare L. Its structure was established as 3,4-dihydroxy-beta-phenylethoxy-O-[beta-D-apiofuranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->3)]-[beta-D-apiofuranosyl-(1-->6)]-4-O-caffeoyl-beta-D-glucopyranoside, on the basis of spectroscopic evidence.     

Compound representatives of a new type of triterpenoid from Aglaia odorata

[structure: see text] A novel triterpenoid, 21,25-cyclodammar-20(22)-ene-3beta,24alpha-diol, has been isolated from Aglaia odorata. Its structure was elucidated on the basis of 1D- and 2D-NMR and MS spectra and then confirmed by X-ray diffraction. It represents a new type of natural five-membered-ring triterpenoid, named cyclodammarane. Its possible biopathway was that squalene-2,3;22,23-diepioxide was directly cyclized to form 24,25-epoxydammar-20(21)-en-3-ol, followed by protonation of the remaining 24,25-epoxide and the cation attacking 21(20) methylene to generate the E ring.     

Colubricidin A, a novel macrolide antibiotic from a Streptomyces sp.

A new 34-membered macrolide antibiotic, colubricidin A (1), was isolated from the fermentation broth of a new streptomyces species. Its structure was elucidated on the basis of analysis of the spectroscopic data and chemical degradation. It was identified as a glycomacrolide with an unprecedented aromatic chromophore. Colubricidin A showed excellent activity against Gram-positive bacteria.     

Fibrarecisin, a novel triterpenoid from Fibraurea recisa with antitumor activity

Fibrarecisin (1), a novel triterpenoid, was isolated from chloroform extract of the stem bark of Fibraurea recisa Pierre. Its structure was elucidated by spectroscopic methods. Compound 1 exhibited significant antitumor activity in vitro against A-549 cancer cell at 10 microM by SRB and MTT methods.     

Codonopiloneolignanin A,a polycyclic neolignan with a new carbon skeleton from the roots of Codonopsis pilosula

A neolignan codonopiloneolignanin A(1) with a novel 2,9:2',9:7,7'-tricyclo-8,'-neolignane skeleton was isolated from an aqueous extract of the Codonopsis pilosula roots. Its structure including the absolute configuration was elucidated by extensive spectroscopic analysis, including 2D NMR and electronic circular dichroism calculation. The proposed biosynthetic pathway of compound 1 is also discussed.     

Ursethoxy acid,a new triterpene from Lantana camara

A new pentacyclic triterpene, named ursethoxy acid (1) was isolated from the aerial parts of Lantana camara Linn. Its structure has been elucidated as 3,25-epoxy-3alpha-ethoxy-urs-12-en-28-oic acid through extensive 1D- and 2D-NMR (COSY-45, NOESY, J-resolved, HMQC and HMBC) studies.     

A DTTA-ligated uridine-quantum dot conjugate as a bimodal contrast agent for cellular imaging

A uridine-quantum dot conjugate, a contrast agent for multimodal imaging, was synthesized. Its T(1) relaxivity was 655 and 571.2 mM(-1) s(-1) per particle at 36 °C in phosphate buffered saline at 60 and 200 MHz, respectively. In vitro multimodal images confirmed its uptake by RAW 264.7 cells.     

2,3'-Dihydroxycanthaxanthin, a new carotenoid with a 2-hydroxy-4-oxo-beta-end group from the hermit crab, Paralithodes brevipes

A new carotenoid with a 2-hydroxy-4-oxo-beta-end group was isolated from the hermit crab, Paralithodes brevipes, as a minor component. Its structure was determined to be 2,3'-dihydroxy-beta,beta-carotene-4,4'-dione (1) by spectral data and the compound was named 2,3'-dihydroxycanthaxanthin. Chiral resolution of 1 by HPLC using a chiral column provided two stereoisomers, 1a and 1b. The 3'R and 3'S chirality were determined for 1a and 1b, respectively, by CD spectra.     

Secoeuphoractin,a minor diterpenoid with a new skeleton from Euphorbia micractina

A minor diterpenoid with a novel carbon skeleton,secoeuphoractin(1),was isolated from an ethanol extract of the roots of Euphorbia micractina.Its structure including the absolute configuration was determined by extensive spectroscopic studies,especially by 2D NMR and CD data analysis,in combination with a plausible biosynthetic pathway associated with co-occurring diverse diterpenoids.This compound showed activity against HIV-1 replication with an IC_(50) value of 1.76 ± 0.61 μmol/L.