[Identification of alkaloids and flavonoids in all parts of Fritillaria thunbergii using LC-LTQ-Orbitrap MSn].

Alkaloids and flavonoids in flowers, flower buds, stems, leaves, and bulbs of Fritillaria thunbergii were identified by LC-LTQ-Orbitrap MSn.Alkaloids were identified by ACQUITY UPLC BEH C18（2.1 mm×50 mm, 1.7 µm ) chromatographic column with a mobile phase of 10 mmol•L⁻¹ ammonium formate-acetonitrile and gradient elution in positive MS scan mode.Meanwhile, flavonoids were analyzed by Agilent-Zorbax SB C18 (4.6 mm×250 mm, 5 µm) chromatographic column with a mobile phase of 0.2% acetic acid-acetonitrile and gradient elution in negative MS scan mode.Combined with literature reports, chemical constituents were identified and determined by accurate molecular weights and fragment ion peaks in the ESI-MS/MS spectra based on high resolution mass spectrometer.In all parts of F.thunbergii, 37 alkaloids including 7 alkaloids (zhebeininoside, peimisine, peimine, peiminine, ebeiedinone/puqiedinone, ebeiedine/ puqiedine, peimisine-N-oxide) were simultaneously analyzed.Moreover, 16 flavonoids including quercetin, kaempferol and their glycosides were identified.The results indicated that the aerial parts had the similar alkaloids as the bulbs on the whole.Meanwhile, it had a series of flavonoids undetected in the bulbs.Our results provided the scientific basis for the development and utilization of aerial parts of F.thunbergii.

New eudesmane-type sesquiterpenoids from the root bark of Pseudolarix kaempferi.

The phytochemical investigation of the root bark of Pseudolarix kaempferi yielded eight eudesmane-type sesquiterpenoids, including three new ones, 1α-hydroxyl-4(14)-en-ß-dihydroagarafuran (1), 1α, 2α-diacetoxy-8ß-isobutanoyloxy-9α-benzoyl oxy-15-ß-(ß-furancarbonyloxy)-4ß, 6ß-dihydroxy-ß-dihydroagarofuran (7), and 1α-acetoxy-2 α-furancarbonyloxy-8ß-isobutanoyloxy-9α-benzoyloxy-15ß-(ß-acetoxy)-4ß, 6ß-dihydroxy-ß-dihydroagarofuran (8). Herein the new compounds 7 and 8 were reported as a mixture. The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including UV, IR, NMR, and MS, and comparison with the literature data.

New isocoumarins and alkaloid from Chinese insect medicine, Eupolyphaga sinensis Walker.

Two new isocoumarins (1 and 2), a new alkaloid (3), and a known N-acetyldopamine dimer (4) were isolated from the ethyl acetate extract of Chinese insect medicine Eupolyphaga sinensis. Their structures were elucidated on the basis of detailed spectroscopic investigations, such as 1D- and 2D NMR spectroscopy, as well as by means of HR-MS. The structure of 1 was firmly confirmed by X-ray crystallography, and the absolute configuration was revealed by experimental and computational optical rotation analyses. Cytotoxicities of 1-4 were measured in vitro against 10 selected cancer cell lines.

The biosynthetic products of Chinese insect medicine, Aspongopus chinensis.

A new oxazole (1) was obtained from Chinese insect medicine Aspongopus chinensis, along with three known N-acetyldopamine derivatives (2-4). Their structures were determined on the basis of NMR and ESI-MS analyses. The possible biosynthetic pathways of the isolated compounds are discussed. Cytotoxicities of those compounds against 10 selected cancer cells were measured in vitro.