Undescribed chalcone and stilbene constituents from Lysimachia baviensis and their anti-inflammatory effect.

The chemical composition and anti-inflammatory activity of the endemic Lysimachia baviensis were investigated for the first time in this study. A phytochemical fractionation of the methanol extract of L. baviensis resulted in the isolation of a new stilbene (bavienside A, 1) and two new chalcone glycosides (baviensides B and C, 2 and 3). Their structures were elucidated via the interpretation of NMR and HRESIMS spectroscopic data. Compounds 1-3 strongly inhibited the production of nitric oxide in LPS-induced RAW264.7 cells with the IC50 values of 6.23, 2.86 and 3.51 µM, respectively. The C-acetylstilbene and carbomethyl chalcone structures in compound 1 and 3 were found for the first time from natural source and could be important markers for chemotaxonomy of Lysimachia baviensis.

Chevalierinol A and B, two new neolignan sesquiterpenoids from Magnolia chevalieri.

Two new neolignan sesquiterpenoids, chevalierinol A (1) and chevalierinol B (2), were isolated from the ethyl acetate extract of Magnolia chevalieri leaves, together with twelve known compounds (3-14). Their structures were elucidated by analysis of spectroscopic data including 1D, 2D and mass spectra and compared with the reported data. Compounds 1, 3, 4, 6, 7, 10 were evaluated for their inhibitory effect against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 macrophage cells.

Premna vietnamensis (Lamiaceae, Premnoideae), a distinct new species from the Central Highlands of Vietnam.

Premna vietnamensis, a distinct new species which is endemic to Gia Lai Province in Central Highlands of Vietnam, is described and illustrated. It is characterized by its calyx tube bearing a semi-globose fleshy appendage, which has not been reported before from all known congeneric taxa, as well as from the Lamiaceae. A phylogenetic analysis of the whole Lamiaceae based on a sampling including representatives from all 12 currently recognized subfamilies confirmed the placement of this new species within Premna of the Premnoideae. Morphologically and geographically, P. vietnamensis is most similar to P. stenobotrys, but differs significantly in many aspects.

Evolution of sexual systems and growth habit in Mussaenda (Rubiaceae): Insights into the evolutionary pathways of dioecy.

Dioecy is a rare sexual system that is thought to represent an "evolutionary dead end". While many studies have addressed the evolution of dioecy and/or its relationship with the evolution of the woody habit, few have explored the relationship between dioecy and climbing habit, and their effects on diversification rates. Here, we study the evolution of sexual systems and growth habit in Mussaenda (Rubiaceae) using a robust phylogeny of the genus based on eight plastid regions and a broad sampling of taxa (92 of the 132 species were sampled). A time-calibrated tree was constructed to estimate diversification rates in different clades and its correlates with focal characters. More specifically, we assess evolutionary correlations between dioecy and climbing habit and their respective influences on diversification rates. Ancestral character state reconstructions revealed that distyly is the most likely ancestral state in Mussaenda. Distyly has subsequently given rise to dioecy, short-styled floral monomorphism, and long-styled floral monomorphism. Dioecy has evolved independently at least four times from distyly, and has reversed to homostylous hermaphroditism at least twice, which does not support the "evolutionary dead end" hypothesis. A significant correlation between the evolution of dioecy and climbing growth form was found in Mussaenda. It is possible that a strong association between high net diversification rates and dioecy may exist in Mussaenda, but no association was found with climbing habit.

Integrated Analysis of the Wood Oil from Xanthocyparis vietnamensis Farjon & Hiep. by Chromatographic and Spectroscopic Techniques.

In order to get better knowledge about the volatiles produced by Xanthocyparis vietnamensis, a species recently discovered in Vietnam, its wood oil has been analyzed by a combination of chromatographic (GC, CC) and spectroscopic (GC-MS, (13)C-NMR) techniques. Forty components that accounted for 87.9% of the oil composition have been identified. The composition is dominated by nootkatene (20.7%), 11,12,13-tri-nor-eremophil-1(10)-en-7-one (17.2%), γ-eudesmol (5.1%), nootkatone (4.7%), valencene (3.5%) and 13-nor-eremophil-1(10)-en-11-one (2.6%). The structure of two new compounds-10-epi-nor-γ-eudesmen-11-one and 12-hydroxy-isodihydroagarofuran-has been elucidated, while 11,12,13-tri-nor-eremophil-1(10)-en-7-ol is reported as a natural product for the first time. The composition of X. vietnamensis wood oil varied drastically from those of leaf oils, dominated by hedycaryol (34.4%), phyllocladene (37.8%) or by pimara-6(14)-15-diene (19.4%).