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Pentacordinated phosphoranes containing valine or iso-leucine residue (2-phenyl-2, 75-spiro[1,3,2-phenanthrodioxaphosphole-2,2'-1,3,2-oxazaphospholan]-5';-one)were synthesized through sequential two-step reactions, whereby the reaction products of phenyldichlorophosphine with N,O-bis(trimethylsilyl)valine or iso-leucine were followed by the addition of phenanthrenequione, and the crystals of 4a and 4b were obtained from benzene and hexane mixed solution. The x-ray structure of the crystals 4a and 4b revealed that they are distorted TBP, exhibiting R[subp] absolute configuration. The 31[subP] NMR spectra showed that the S[subp] diastereomer could transfer into the other one R[subp] that came out from the solution during crystallization. Correspondingly, when it was dissolved in solvents the Re diastereomer transferred into the other one S[subp], and the pair of diastereomers changed each other in solution at room temperature through a phosphonium carboxylate zwitterions intermediate. [ABSTRACT FROM AUTHOR]

Two new pterocarpenes were isolated from the roots of Hedysarum multijugum, and their structures were elucidated as hedysarimpterocarpene B (1) and hedysarimpterocarpene C (2) on the basis of spectroscopic data. [ABSTRACT FROM AUTHOR]

Three phenolic glucosides were isolated from Oxytropis myriophylla . On the basis of spectral analyses, their structures were elucidated as 2-methoxy-4-(3′-hydroxy- n -butyl)-phenol-1- O -β- d -glucopyranoside ( 1 ), syringin ( 2 ), 2-methoxy-4-(3′-hydroxy-propenyl)-phenol-1- O -β- d -glucopyranoside ( 3 ). Compound ( 1 ) is a new phenolic glucoside named myriophylloside A, the other two compounds are isolated from this plant for the first time. [ABSTRACT FROM AUTHOR]