Robtin

Journal of the Korean Wood Science and Technology,2000,28(3):52-61.

Extractives of the Wood of Black Locust and the Bark of Poplar as Decay-Resistant Hardwood Tree Species.[Reference: WebLink]

METHODS AND RESULTS:
Black locust(Robinia pseudoacacia) and poplar(Populus alba glandulosa) trees were collected, extracted with acetone-(7:3, v/v) after drying, fractionated with hexane, chloroform and ethylacetate, and freeze dried to get some brown powder. Each fraction of the powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-hexane mixture as eluting solvents.
CONCLUSIONS:
The wood extractives of black locust contained (+)-leucorobinetinidin as flavan, Robtin as flavanone and dihydrorobinetin as flavanonol, and robinetin as flavonol. The poplar bark extractives contained various kinds of phenolic compounds : (+)-catechin as flavan, naringeoin, eriodictyol, sakuranetin, aromadendrin and taxifolin as flavanonol, salireposide as salicin derivative, and minor compounds such as aesculin and p-coumaric acid. However, aesculin has not been reported as a constituent of the poplar bark in Korea yet. NMR and FAB-MS analyses were done to elucidate the structures of isolated phenolic constituents.