摘要:

A new flavonol glycoside characterized as quercetin 8-C-α-β-rhamnosyl (1→2) glucoside (1) together with quercetin 3-O-β-D-glucoside (2), quercetin 3-O-α-L-rhamnoside (3), quercetin (4) and kaempferol (5), have been isolated from the methanol extract of the leaves.

ISSN:1057-5634    

DOI:10.1080/10575639508043206

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Rosmarinic acid (α-O-caffeoyl-3,4-dihydroxy phenyllactic acid) is the main phenolic constituent (1.0–7.0 μmol/kg) present in methanolic extracts of the medium fromLavandula × intermediacell cultures which have been grown on agar gel containing Murashige & Skoog medium. In this medium, the concentration of FeSO4is 100 μmol/kg. Since rosmarinic acid yields a blue pigment upon reaction with FeSO4(λmax= 572 nm and ϵ572= 3,820 M−1cm−1at pH 6.0), this this pigment appears to be the main compound responsible for the blue colour which is secreted into the medium byLavandula × intermediacell cultures grown in the dark.

ISSN:1057-5634    

DOI:10.1080/10575639508043207

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The biosynthetic origin of all 19 carbon atoms of the phenyl-phenalenones was established by13C NMR analysis of hydroxyanigorufone, isolated from cultured roots ofAnigozanthos preissiiafter administration of13C labelled precursors. High incorporation of C-2 of [2-13C]acetate into the central carbon atom for the first time unambiguously proved the origin of this C1unit of phenylphenalenones.

ISSN:1057-5634    

DOI:10.1080/10575639508043208

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

A new dihydroxycembranolide, sandensolide has been isolated along with (+)-sinulariolide from the ethyl acetate extract of the soft coralSinularia sandensisVerseveldt. The structure and stereochemistry of the new compound was determined by its spectral data [UV, IR,1H &13C NMR, 2D NMR (1H-1H COSY) and Mass], chemical conversion and X-ray analysis.

ISSN:1057-5634    

DOI:10.1080/10575639508043209

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Novel indole alkaloids of the aspidosperma-type were obtained in minor amounts from the leaf extract ofTabernaemontana divaricata(double flower variety). The structures of these alkaloids were elucidated by spectral methods.

ISSN:1057-5634    

DOI:10.1080/10575639508043210

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Reaction of compound (4) with (5) give a mixture of the isomers (7) and (8) through the intermediate (1). Further conversions led through the oxo- (9), (10) and thioxo (11), (12) derivatives to (±)-19-ethoxycarbonyl-19-demethylvincadifformine (3), and (±)-18-methoxycarbonyl-D(14)-norvincadifformine (13). The preparation of the former compound constitutes the formal synthesis of (±)-12-demethoxy-N(1)-acetylcylindrocarine (2). Oxidative ring transformation of the latter gave (±)-21-methoxycarbony 1-D(18)-norapovincamine (14).

ISSN:1057-5634    

DOI:10.1080/10575639508043211

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The absolute configuration assignment of (-)-magnofargesin (1) was achieved by the isomerization of1to (+)-magnolin.

ISSN:1057-5634    

DOI:10.1080/10575639508043212

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

The new phenolic triterpenes, blepharodol (5) and 7α-hydroxy-blepharodol (6) were isolated fromMaytenus blepharodesand canarol (8), 7α-hydroxy-canarol (9), 7-hydroxy-6-oxoiguesterol (11), canaradial (12) and the triterpene methylene quinones iguesteroquinone (13) and 7α-hydroxy-7,8-dihydro-iguesterin (14) and were isolated fromMaytenus canariensis. Their structures were elucidated by means of1H and13C NMR spectroscopic studies, including homo and heteronuclear correlations, DEPT, COSY, HMQC and HMBC experiments. These products are intermediates in the biogenetic pathway of methylene quinone triterpenes.

ISSN:1057-5634    

DOI:10.1080/10575639508043213

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Two novel alkaloids, 1-oxo-1,2-dihydro-12-demethyl-12-hydroxyacronycine (1) and 2,3-dicarbomethoxy-1-methyl-4(1H)-quinolinone (3) have been isolated from the leaves ofSarcomelicope dogniensis. The biogenesis of this latter most probably involves oxidation of the A aromatic ring of a 1,2,3,4-tetra-O-subtituted acridone, such as melicopidine.

ISSN:1057-5634    

DOI:10.1080/10575639508043214

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor

摘要:

Starting from (-) vincadifformine (1), (+) 16-hydroxymethylgoniomitine (10), a derivative of the indole alkaloid (-)goniomitine (5), was synthesizedviathe rearranged compound3.

ISSN:1057-5634    

DOI:10.1080/10575639508043215

出版商:Taylor & Francis Group    

年代:1995

数据来源: Taylor