A Middle Eocene lowland humid subtropical "Shangri-La" ecosystem in central Tibet.

Tibet's ancient topography and its role in climatic and biotic evolution remain speculative due to a paucity of quantitative surface-height measurements through time and space, and sparse fossil records. However, newly discovered fossils from a present elevation of ∼4,850 m in central Tibet improve substantially our knowledge of the ancient Tibetan environment. The 70 plant fossil taxa so far recovered include the first occurrences of several modern Asian lineages and represent a Middle Eocene (∼47 Mya) humid subtropical ecosystem.

A new furostanol saponin from Asparagus cochinchinensis.

A new furostanol saponin, (25S)-26-O-β-D-glucopyranosyl-5β-furost-20(22)-en-3β, 15β,26-triol-3-O-[α-L-rhamnopyranosyl-(1-4)]-β-D: -glucopyranoside, namely, aspacochioside D (1) were isolated from Asparagus cochinchinensis (Lour.) Merr, along with three known saponins, aspacochioside C (2), (25S)-5β-spirostan-3β-yl-O-[O-α-L-rhamnopyranosyl-(1-4)]-β-D-glucopyranoside (3), and pseudoprotoneodioscin (4). The structure of 1 was elucidated on the basis of chemical reactions and spectral analysis (IR, GC, ESI-MS, (1)H-NMR, (13)C-NMR, DEPT, HMBC, HMQC and NOESY).

Lignans from Trachelospermum jasminoides.

Seven lignans having a diarylhydroxybutyrolactone skeleton were isolated from the leaves and stems of Trachelospermum jasminoides (Lindl.) Lem. Their structures were elucidated to be nortrachelogenin 8' -O-beta-D-glucopyranoside (1), nortrachelogenin 5'- C- beta-D-glucopyranoside (2), trachelogenin amide (3), nortracheloside, trachelogenin, tracheloside, and trachelogenin 4'- O- beta-gentiobioside, respectively, on the basis of spectroscopic analyses.

[Studies on chemical constituents of Ervatamia hainanensis].

Objective: To study the chemical constituents of Ervatamia hainanensis.

Method: The compounds were separated and purified by column chromatography with silica gel, and identified by IR, MS, NMR and 2D-NMR.

Result: Five compounds were identified as I (isolariciresinol 9-O-beta-D-glucopyranoside), II (cycloartenol), III (beta-amyrin acetate), IV (beta-sitosterol), V (daucosterol), respectively.