The 1H and 13CNMR spectra of some representative biflavonoids have been reinvestigated by proton-detected C-H correlation. Some assignments made in earlier publications are revised. Rules for the influence of one flavonoid moiety upon the chemical shift of the other’s protons are given.

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From Anacolia webbii the following five biflavonoids could be isolated: 2,3-dihydrophilonotisflavone, philonotisflavone, dicranolomin, 5′,3‴-dihydroxyamentoflavone and 5′,3‴-dihydroxyrobustaflavone. The compounds were identified spectroscopically.

. From Pilotrichella cuspidata the new biflavonoid 3′,3‴ -binaringenin was isolated. Its structure was elucidated spectroscopically.

In Plagiomnium cuspidatum the three new dihydrobiflavones 2,3-dihydro-5′-hydroxyam entoflavone, 2,3-dihydro-5′,3‴-dihydroxyamentoflavone and 2,3-dihydro-5′-hydroxyrobustaflavone were detected.