Isolation and structural determination of new metabolites from Artemisia asiatica roots

Two new 2,2-dimethyl-chromene derivatives and the new pentaisovaleryl sucrose were isolated from the roots of Artemisia asiatica together with the known 1-(5-acetyl-2,4-dihydroxy-phenyl)-3-methyl-butan-1-one, 6-hydroxytremetone and (E)-coniferyl aldehyde. The structures of the compounds were elucidated by extensive 1D (1H, 13C and JMOD) and 2D (1H–1H COSY, HSQC, HMBC and NOESY) NMR studies and APCIMS and HRESIMS investigations. 6-Acetyl-3,7-dihydroxy-2,2-dimethyl-chromene and 6-acetyl-3-hydroxy-2,2-dimethyl-chromene are biogenetically related to 1-(5-acetyl-2,4-dihydroxy-phenyl)-3-methyl-butan-1-one and 6-hydroxytremetone as all having isoprenoid acetophenone origin. All the isolated compounds were described for the first time from this species; interestingly none of them are related to the metabolites identified from the extracts of the aerial part of the plant.