Alnus japonica

Alnus japonica (Thunb.) Steudel A. japonica (Thunb.) Steudel var. koreana Callier Ce Yan (Japanese alder) (leaf, bark) Alpha-amyrin, betulinic acid, glutin-5-en-3-ol, heptacosane, lupenone, taraxerol.48-50 Antitumor. 

Alnus japonica (Thunb.) Steudel, A. japonica (Thunb.) Steudel var. koreana Callier... 

Aleurites fordii, Alnus japonica, Cirsium chinense, C. japonicum, Pedicularis resupinata Sambucus formosana Antiaris toxicaris Antiaris toxicaris... 

Litchi chinensis, Pueraria montana, P. thunbergiana Ficus carica, Dioscorea opposita Alnus japonica... 

Adenophora triphylla, A. verticillata, Alnus japonica, Firmiana simplex... 

Ullmann reaction (4, 33-34). Semmelhack et al.1 recorded details of the coupling of aryl and vinyl halides with Ni(0) complexes, (COD)2Ni or Ni[P(C6H5)3]4. This reaction was used for the first synthesis of almusone (3), an antileukemic lignan obtained from the wood of Alnus japonica Steud. In the case of ort/io-substituted aryl iodides such as 1, reduction becomes a competing reaction and the yields are only moderate. In fact o,o-disubstituted aryl halides cannot be coupled under these conditions. Deliberate addition of a proton source increases formation of the reduction product. Acetic or trifluoroacetic acid are useful for this purpose. Added triphenyl-phosphine also promotes reduction. 

From Alnus species i.e. varieties of alder, containing also a large variety of open chain diarylheptanoids (7-21), some biaryl type macrocyclic compounds have also been isolated. In Alnus japonica Steud. indigeneous in Japan Nomura et al. found four diphenols of this kind. The constitution of alnuson (80) and alnusoxide (81) was elucidated in 1975 (20), while alnusdiol (82) and its oxidation product, alnusonol (83) were characterized in 1981 (17). It was observed that 81 could only be isolated from the dried plant and may be therefore an artefact. Alnusdiol was optically active and therefore a trans-diol but its absolute configuration remained unknown. 

Nomura M, Tokoroyama T 1975 Further phenolic components from Alnus japonica Stend. J Chem Soc Chem Commun 316-317... 

Nomura M, Tokoroyama T, Kubota T 1981 Bisarylheptanoids and other constituents from wood of Alnus japonica. Phytochemistry 20 1097-1104... 

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