摘要:

The rhizomes ofHedychium coronarium(Zingiberaceae) have yielded two new diterpenes which have been identified by spectroscopic methods, notably long-range heteronuclear coupling (HMBC). Coronarin-D methyl ether is a labdane diterpene typical of those previously isolated from this species. The second compound, identified as 14,15,16-trinorlabda-8(17),11-(E)-dien-13-al, appears to be an unusual trinorditerpene catabolite which could be formed by degradation of the normal labdanes produced by this species.

ISSN:1057-5634    

DOI:10.1080/10575639308043856

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Three new sesquiterpenoid lactones (1-3) of the germacrane and elemane classes have been isolated from the Mediterranean octocoralMaasella edwardsi. The structure determinations were accomplished by spectroscopic analysis and supported by molecular mechanics and dynamics calculations.

ISSN:1057-5634    

DOI:10.1080/10575639308043857

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The dienone (3β,15-dimethoxy-5,8-labdadien-7-one), obtained from 7-labdadien-3β,15-diol, is transformed into a phenol by aromatization of ring B. By a cross-coupling reaction catalyzed by Pd(0) the phenol triflate affords fregenedadiol dimethyl ether.

ISSN:1057-5634    

DOI:10.1080/10575639308043858

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

A novel quinolone derived alkaloid of the phenanthridine type, phenaglydon (2), has been isolated from the lipophilic leaf extract ofGlycosmis cyanocarpa(Rutaceae) together with schinifoline (1), a prenylated 2-quinolinone characterized by a diene grouping in the side chain. Both structures have been elucidated on spectroscopic evidence. In the case of phenaglydon the proposed structure has additionally been confirmed by synthesis. The co-occurrence of these alkaloids suggests close biogenetic connections between the two compounds.

ISSN:1057-5634    

DOI:10.1080/10575639308043859

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In the course of synthesizing deethylcatharanthine (lc), treatment of the indolyl-acetyl derivative (4c) with AgBF4resulted in interesting rearranged products (7), (8) and (9).

ISSN:1057-5634    

DOI:10.1080/10575639308043860

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Variabilin (1), an antimicrobial furanosesterterpene, has been isolated from an Okinawan marine spongeAmphidmedonsp. and its absolute stereochemistry at the C-18 position was determined asSby synthesis of a degradation product of1.

ISSN:1057-5634    

DOI:10.1080/10575639308043861

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

The steroid ergosta-4, 6, 8 (14), 22-tetraen-3β-ol is formed, presumably enzymatically from ergosterol, in injured specimens of the edible mushroomMarasmius oreades.

ISSN:1057-5634    

DOI:10.1080/10575639308043862

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Two novel sulphated polyhydroxysteroids,1, possessing potent cytotoxic activity, and2, which proved to be cytoprotective against HIV-1, have been isolated from the Antarctic ophiuroidOphiosparte gigas, together with the known tetrol disulphated3. The structures of1and2have been determined to be cholest-5-ene-2α,3α,4β, 21-tetraol 3, 21-disulphate and cholest-5-ene-2β,3α, 21-triol 2, 21-disulphate, respectively.

ISSN:1057-5634    

DOI:10.1080/10575639308043863

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

In addition to neoliacine and neoliacinic acid previously reported, three new germacranolides, named neoliacinolide A, B, and C, were isolated from the leaves ofNeolitsea aciculataKoidz., and their structures were elucidated by spectroscopic analysis.

ISSN:1057-5634    

DOI:10.1080/10575639308043864

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor

摘要:

Two novel natural products, both glucosides with unusual aglycones, have been isolated from the fruits ofAmmi majusL. Their structures were elucidated by 1D and 2D NMR techniques and other spectroscopic evidences.

ISSN:1057-5634    

DOI:10.1080/10575639308043865

出版商:Taylor & Francis Group    

年代:1993

数据来源: Taylor