Triumfettamide and Triumfettoside Ic,Two Ceramides and Other Secondary Metabolites from the Stems of Wild Triumfetta cordifolia A. Rich. (Tiliaceae)

Two new ceramides, triumfettamide ( 1 ) and triumfettoside Ic ( 2 ), characterized as (2R,6Z)‐2‐hydroxy‐N‐[(2S,3S,4R)‐1,3,4‐trihydroxyhexacosan‐2‐yl]heptadec‐6‐enamide and (2R)‐N‐{(1S,2R,3E,6Z, 9Z,12Z,15Z)‐1‐[(β‐D ‐glucopyranosyloxy)methyl]‐2‐hydroxyheneicosa‐3,6,9,12,15‐pentaen‐1‐yl}‐2‐hydroxytetradecanamide, respectively, were isolated from the stems of Triumfetta cordifolia A. Rich. besides eight known secondary metabolites identified as heptadecanoic acid, β‐sitosterol glucopyranoside, friedelin, lupeol, betulin, maslinic acid, 2‐hydroxyoleanolic acid and the mixture of stigmasterol and β‐sitosterol. Their structures were determined on the basis of spectroscopic methods as well as HR‐MALDI‐FT‐ICR‐MS analysis, chemical transformation, and by comparison of their physical and spectral data with those reported in the literature and with authentic specimens for some known compounds. Five pentacyclic triterpenoids, friedelin, lupeol, betulin, maslinic acid, and 2‐hydroxyoleanolic acid, have been isolated from Triumfetta genus for the first time.     

Two New Diterpenes from the Twigs of Cinnamomum cassia

Two new diterpene derivatives named cinnacasol ( 1 ) and cinnacaside ( 2 ) were isolated from the MeOH extract of the twigs of Cinnamomum cassia Blume . Their structures were identified based on physicochemical properties and spectroscopic‐data analyses such as IR, HR‐MS, and 1D‐ and 2D‐NMR, and by comparison with published values.     

Two New Antibacterial Anthraquinones from the Twigs of Cassia alata

Chemistry of Natural Compounds - Two new anthraquinones, 2,6-dimethyl-3-hydroxy-5-methoxyanthraquinone (1) and 2,5-dimethyl-6-hydroxy-3-methoxyanthraquinone (2), were isolated from the twigs of...     

A New Ceramide from the Ascomycete Tuber indicum

A new C-18 phytosphingosine derivative (1) was isolated from the fruiting bodies of Tuber indicum. Its structure was established as (2S,3S,4R,2′R)-2-N-(2′-hydroxytricosanoyl)-octadecan-1,3,4-triol by spectral and chemical methods.     

A New Ceramide from the Basidiomycetes Armillaria mellea

As one part of our study on the bioactive metabolites of the higher fungi in Yunnan Province, the chemical constituents of Armillaria mellea (Tricholomataceae) collected at Zhong Dian in Yunnan Province have been investigated. The present report deals with the structural elucidation of a new ceramide 1, named armillaramide, isolated from the AcOEt extract of the fruiting bodies of this fungus.Figure 1 The structure of armillaramide 1Compound 1, white amorphous powder, mp 113(117(C, [(] + …     

New Triterpenoid Fatty Acid Esters from the Small Twigs of Viburnum Odoratissimum

α‐Amyrin margarate ( 1 ), moretenyl margarate ( 2 ) and moretenyl palmitate ( 3 ), three triterpenoid fatty acid esters, have been isolated from the acetone extract of the small twigs of Viburnum odoratissimum in addition to the three known compounds, α‐amyrin palmitate ( 4 ), ursolic acid ( 7 ) and vibsanin‐K ( 8 ). The structures of compounds 1–3 were elucidated based on extensive spectroscopic analysis and alkaline hydrolysis. Preliminary pharmacological studies revealed that vibsanin‐K and ursolic acid exhibited significant cytotoxicity against human gastric (NUGC) and oral epidermoid (HONE‐1) tumor cells at a concentration of 50 μg/mL while compounds 1–3 were inactive.     

A New Ceramide from the Soft Coral Cladiella humesi Verseveldt

Ceramides are increasingly becoming important compounds because of their markedbiological activity. The 2000 International Gordon Research Conference on "Glycolipidand Sphingolipid Biology" will be held in May in italy. It has been recently found thatceramides inhibit Cholesteryl Ester Transfer Protein (CETP)'. Elevation in CETP leadsto atherosclerotic cardiovascular diseases2. A literature survey showed that ceramideswere antifungal', and some of these showed antimicrobial and cytotox…     

Alkaloids from the Twigs of Catharanthus roseus

Chemistry of Natural Compounds -     

Phlomisamide and Phlomisteriod: A New Ceramide and a New Stigmasterol Derivative from Phlomis cashmeriana

Phlomisamide ( 1 ), a new ceramide, and a new stigmasterol derivative, phlomisteriod ( 2 ), have been isolated from Phlomis cashmeriana. Their structures were elucidated by comprehensive analysis of their 1D‐ (¹H‐ and ¹³C‐NMR) and 2D‐NMR (COSY, HMQC, HMBC), and HR‐EI‐MS data.     

Tanacetamide D: A New Ceramide from Tanacetum artemisioides

One new ceramide (=long‐chain base linked to a fatty acid via an amide bond), tanacetamide D ( 1 ), was isolated from Tanacetum artemisioides. Besides this, the two known constituents 5‐demethylnobiletin ( 2 ) and 5‐hydroxy‐3,6,7,8,3′,4′‐hexamethoxyflavone ( 3 ) were isolated for the first time from this species. The structure elucidation of the isolated compounds were based primarily on 2D‐NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple‐quantum coherence (HMQC), heteronuclear multiple‐bond correlation (HMBC), and nuclear Overhauser effect spectroscopy (NOESY) experiments.     

Citropremide and Citropridone: A New Ceramide and a New Acridone Alkaloid from the Stem Bark of Citropsis gabunensis

The structure elucidation and complete ¹H‐ and ¹³C‐NMR assignments are reported for two new compounds: the ceramide citropremide ( 1 ), and the acridone alkaloid citropridone ( 2 ). Both of these secondary metabolites were isolated from the stem bark of Citropsis gabunensis. High‐resolution mass, IR and UV spectrometry, and NMR experiments including COSY, HMQC, and HMBC were used for the determination of the structures and NMR spectral assignments.     

Limonoids from the Twigs and Leaves of Chukrasia tabularis

Seven new limonoids, tabularisins J–P ( 1 – 7 , resp.), together with eight known compounds, were isolated from the twigs and leaves of Chukrasia tabularis. Their structures were determined primarily by spectroscopic methods. The potassium channel blocking activities of some of these isolates were evaluated, and a few of them exerted significant activities on the delayed rectifier (I_K) K⁺ current.     

Three New Derivatives and Others Constituents from the Roots and Twigs of Trilepisium madagascariense DC

Three new compounds, trilepisflavene ( 1 ), trilepisdepsidone ( 2 ), and daturadiol stearate ( 3 ), together with nine known compounds, 2‐hydroxy‐4‐[(4‐hydroxy‐2‐methoxy‐6‐methylbenzoyl)oxy]‐6‐methylbenzoic acid ( 4 ), lichexanthone ( 5 ), naringenin ( 6 ), 3′,4′,5,7‐tetrahydroxyflavanone ( 7 ), 2‐hydroxybenzoic acid ( 8 ), methyl 2,4‐dihydroxy‐6‐methylbenzoate ( 9 ), β‐amyrin ( 10 ), eurothridiol palmitate ( 11 ), and β‐sitosterol ( 12 ), were isolated from the AcOEt extract of the twigs and the roots of Trilepisium madagascariense. Acetylation of eurothridiol palmitate was carried out and a new acetylated derivative ( 13 ) was obtained. The structures of the isolated and acetylated compounds were elucidated on the basis of spectroscopic analysis. Antimicrobial activity of all these compounds was evaluated using Mueller–Hinton broth (MHB) and Mueller–Hinton agar (MHA) method. Trilepisdepsidone , 2‐hydroxy‐4‐[(4‐hydroxy‐2‐methoxy‐6‐methylbenzoyl)oxy]‐6‐methylbenzoic acid, 3′,4′,5,7‐tetrahydroxyflavanone, and naringenin exhibited moderate to weak antimicrobial activity.     

Alkaloids from the Twigs and Leaves of Daphniphyllum macropodum

Three new alkaloids, macrodumines A–C ( 1 – 3 , resp.), along with ten known analogs, were isolated from the twigs and leaves of Daphniphyllum macropodum. Their structures were elucidated on the basis of spectroscopic methods. The 11‐OH configuration of the known alkaloid hydroxydaphgraciline ( 4 ) was assigned as α for the first time by comparing the NMR data with those of macrodumine C ( 3 ).     

Hemislin B Glucoside,a New Lignan from Hemistepta Lyrata

From the ethanolic extract of the whole plant of Hemistepta lyrate Bunge., a new lignan, named hemislin B glucoside,has been isolated and identified as α-(trans-3-methoxy-4-O-β-D-glucopyranosylbenzylidene)-β-(3,4-dimethoxybenzyl)-γ-butyrolactone. Its structure has been established on the basis of UV,IR,FABMS,^1H-NMR,^13C-NMR,HMQC and HMBC spectral analysis.