The syntheses of both enantiomers of phaselic acid (2-O-caffeoylmalate) are described. The previously unreported acetate-protected caffeic acid anhydride was used with appropriately protected malic acid derivatives as coupling partners to provide fully protected phaselic acid. Sequential unmasking of the protecting groups afforded phaselic acid in an acceptable overall yield. Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) to view the free supplemental file.
An Approach to the Chemotaxonomic Differentiation of Two European Dog's Mercury Species: Mercurialis annua L. and M. perennis L.
作者:Peter Lorenz、Sarina Duckstein、Jürgen Conrad、Matthias Knödler、Ulrich Meyer、Florian C. Stintzing
DOI:10.1002/cbdv.201100341
日期:2012.2
specific differences were observed for particular n-alkylresorcinol homologs. Finally, the investigation of H(2) O extracts by LC/MS/MS revealed the presence of depside constituents. Whereas, in M. perennis, a mixture of mercurialis acid (=(2R)-[(E)-caffeoyl]-2-oxoglutarate) and phaselic acid (=(E)-caffeoyl-2-malate) could be detected, in M. annua solely phaselic acid was found. By comparison with synthesized
Mercurialis annua和M. perennis是用于补充医学的药用植物。在目前的工作中,建立了允许通过化学标记化合物化学区分紫花念珠菌和多年生念珠菌的分析方法。除以前发表的化合物外,从GC / MS证实了从青蒿的草药部分获得的CH(2)Cl(2)提取物中吡啶-3-甲腈和烟酰胺的排他性存在。值得注意的是,吡啶-3-甲腈首次被鉴定为天然产物。CH(2)Cl(2)提取物通过聚酰胺的进一步色谱分离产生了MeOH馏分,该馏分表现出宽谱的侧链饱和正烷基间苯二酚。尽管两种植物的正烷基间苯二酚模式相似,对于特定的正烷基间苯二酚同源物观察到一些特定的差异。最后,通过LC / MS / MS对H(2)O提取物进行的调查显示,存在后代成分。而在百日咳杆菌中,可以检测到鱼尿酸(=(2R)-[((E)-咖啡酰]]-2-氧戊二酸)和相酸(=(E--咖啡酰-2-苹果酸)的混合物仅发现了M. annua的相酸
Subulatin, an Antioxidic Caffeic Acid Derivative Isolated from the<i>In Vitro</i>Cultured Liverworts,<i>Jungermannia subulata</i>,<i>Lophocolea heterophylla</i>, and<i>Scapania parvitexta</i>
The new caffeic acid derivative, subulatin (1), was isolated from in vitro cultured liverworts, Jungermannia subulata, Lophocolea heterophylla, and Scapania parvitexta. The structure of 1 involved two caffeic acids, D-glucose, and 2-carboxy-6-(1,2-dihydroxy-ethyl)-4,5-dihydroxy-5,6-dihydro-4H-pyran. The connectivity of those and the absolute stereochemistry of 1 were elucidated on the basis of spectroscopic