Alkaloids from stems of Ervatamia yunnanensis

Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis. Among them, yunnanensine (I) is new. The other five are known alkaloids, namely: 19,20-E-vallesamine (II), 19s-heyneanine (HI), ibogaine (IV), ibogamine (V), coronaridine (VI). The structural elucidation of the alkaloids was based on spectral means.     

Two New Oxindole Alkaloids from Ervatamia yunnanensis

ErvalanIiaYunnanensiSTsianghasbeenusedasafolkmedicineinChinaforthetreatmentofhypertensi0n'.Aspart0fourc0ntinuingpr0gramonthestudyofplant-derivedbioactivecomp0unds,thechemicaIconstituents0fE.yunnanensI1vgrowinginYunnanwereinvestigated.Intheprevi0uspaper,werep0rtedthestructuresofind0lealkal0ids;l9S-hydr0xy-tacamine,tabernaemontanine,l7-demethoxy-c0rynoxineB,l7-demethoxy-hydr0c0rynoxineB,20-epi-ervatamine,19,2O-dehydroervatamine,includinganewone,l9S-hydroxy-16-epi-tacaminefr0mthisspecies'.T…     

Indole Alkaloids from the Roots of Ervatamia hainanensis

Evratamia hainanensis Tsiang, is distributed in the mountain and forest regions of 100-500 metres height in the southern part of China. Its root has been used for the treatment of stomachache, dysentery, rheumatic arthritis, hypertension and virus hepatit…     

Alkaloids from Stems of Ervatamia yunnanensis (II)

The non-alkaloid chemical constituents, which were isolated from the stems of Ervatamia yunnanensis Tsiang (Apocynaceae), have been reported in previous paper 1. As a part of our continuing research on the isolation of active compounds for anti-addictive …     

A new stereoisomer of stemmadenine alkaloid from Tabernaemontana heyneana

A new alkaloid, 15‐β‐stemmadenine, was isolated from the fruits of Tabernaemontana heyneana Wall. from the ethanolic extract. The complete ¹H and ¹³C NMR assignments of the compound were carried out using COSY, HMQC and HMBC. Stereochemistry at C‐15 and C‐16 was established using ROESY and temperature‐dependent ¹H NMR studies. Copyright © 2002 John Wiley & Sons, Ltd.     

Biotransformation of Valdecoxib by Plant Cell Cultures

Valdecoxib is a new anti-inflammatory drug that is highly selective for inhibition of the inducible form of cyclooxygenase (COX-2). In the present study, biotransformation of valdecoxib was investigated in cell cultures of five medicinal plants, viz., Catharanthus roseus, Azadirachta indica, Capsicum annuum, Ervatamia heyneana, and Nicotiana tabacum. Identification of the biotransformed products was carried out by using high-performance liquid chromatography coupled with diode array detection and liquid chromatography–tandem mass spectrometry analysis. All the cultures transformed valdecoxib into more polar compounds, and C. roseus also produced one unknown compound that is less polar than the substrate. The reactions performed by these plant cell cultures include hydroxylation, methylation, and demethylation. Optimization studies were performed to investigate the effect of the day of extraction and substrate concentration on biotransformation.     

Two New Norisoprenoid Derivatives from the Red Alga Gymnogongrus flabelliformis

Gymnogongrus flabelliformis Hav. is a red alga belonging to Phyllophoraceae family (Gigartinales order), and widely distributed along the coast of China Sea1. Up to now no chemical constituent of this species has been reported. As a part of our program to assess systematically the chemical and biological diversity of seaweeds distributed in China Sea2-4, the red alga G. flabelliformis was collected along the coast of Qingdao, Shandong Province. We report herein the isolation and structural…     

Alkaloids from Stems of Ervatamia yunnanensis （Ⅱ）

Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis. Among them, 10-hydroxy-19, 20-dihydroisositsirikine （I） is new. The other five are known alkaloids, namely： matrine （Ⅱ）, 19, 20-dihydroisositsirikine （Ⅲ）, 19-s-voacangarine （Ⅳ）, 1 l＇-methoxyl-19s- heyneanine （Ⅴ）, conodurine （Ⅵ）. The structural elucidation of the alkaloids was based on spectral means.     

Flabelliformides A and B,Two Novel Indole Alkaloids from Ervatamia flabelliformis

Flabelliformides A ( 1 ) and B ( 2 ), containing a novel C₂₀ indole core, have been isolated from the stems of Ervatamia flabelliformis. The structures of 1 and 2 were elucidated on the basis of spectral analysis and X‐ray crystallography.