Alnus sieboldiana

Alnusiin Alnus sieboldiana (S)-hexahydroxydiphenic acid linked 2,3 valoneic acid linked 4,6 99... 

From alnusin trimethyl ether (3,5,6,7-tetramethoxyflavone) (m.p. 112-112°5) (SM) refluxing in a mixture of 50% potassium hydroxide solution and ethanol for 20 h under nitrogen (50%). SM was prepared by methylation of alnusin (6-methoxy-3,5,7-trihydroxyflavone) (m.p. 239-241°). Alnusin was the main flavonoid isolated from Alnus sieboldiana (Betulaceae) [4971] ... 

Isol. from wood of Pinus spp. and Alnus sieboldiana and other plants. Used as ImAf soln. in EtOH for photometric detn. of U(K7) (2 405 nm, pH 5.5-9.5). Yellow prisms (EtOH). Sol. MeOH, EtOH. Mp 163°. Nadkami, D.R. et al, J. Chem. Soc., 1938, 1320 synth)... 

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