ThepresentreviewdescribesresearchonnovelnaturalisoquinolinealkaloidsandtheirN-oxidesisolatedfromdifferentplantspecies.Morethan200biologicalactivecompoundshaveshownconfirmedantimicro-bial,antibacterial,antitumor,andotheractivities.Thestructures,origins,andreportedbiologicalactivitiesofaselectionofisoquinolineN-oxidesalkaloidsarereviewed.WiththecomputerprogramPASSsomead-ditionalSAR(structure–activityrelationship)activitiesarealsopredicted,whichpointtowardnewpossibleapplicationsofthesecompounds.ThisreviewemphasizestheroleofisoquinolineN-oxidesalkaloidsasanimportantsourceofleadsfordrugdiscovery.

Plants produce many secondary metabolites, which reveal biological activity [...]

Huperzine A (HupA), isolated originally from a traditional Chinese medicine Qiang Ceng Ta, whole plant of Huperzia serrata (Thunb. ex Murray) Trev., a member of the Huperziaceae family, has attracted intense attention since its marked anticholinesterase activity was discovered by Chinese scientists. Several members of the Huperziaceae (Huperzia and Phlegmariurus species) have been used as medicines in China for contusions, strains, swellings, schizophrenia, myasthenia gravis and organophosphate poisoning. HupA has been marketed in China as a new drug for Alzheimer's disease (AD) treatment and its derivative ZT-1 is being developed as anti-AD new drug candidate both in China and in Europe. A review of the chemistry, bioactivities, toxicology, clinical trials and natural resources of HupA source plants is presented.

A simple and efficient HPLC-DAD (225 nm) method was developed and validated for the simultaneous determination of limonin and six key alkaloids (evodiamine, rutaecarpine, 1-methyl-2-undecyl-4(1H)-quinolone, evocarpine, 1-methy-2-[(6Z,9Z)]-6,9-pentadecadienyl-4-(1H)-quinolone, and dihydroevocarpine) in Evodia rutaecarpa (Juss.) Benth, which has been widely used as one of the Traditional Chinese Medicines. The chromatographic separation was carried out on a Hypersil BDS C18 column, and gradient elution was employed with a mobile phase containing acetonitrile and water. Contents of the analytes in 18 batches of samples were analyzed by ultrasonic extraction with ethanol and water mixture (80 : 20, v/v) followed by HPLC analysis. Separation of the seven analytes was achieved within 60 min with good linearity (r > 0.999). The RSD of both the intraday and interday precision was below 1.85%. The accuracy at different concentrations was within the range of 97.91 to 100.49%. Hierarchical ...