Based on the statistics of glacier area variation measured in the Chinese Tianshan Mountains since 1960, the response of glacier area variation to climate change is discussed systematically. As a result, the total area of the glaciers has been reduced by 11.5% in the past 50 years, which is a weighted percentage according to the glacier area variations of 10 drainage basins separated by the Glacier Inventory of China (GIC). The annual percentage of area changes (APAC) of glaciers in the Chinese Tianshan Mountains is 0.31% after the standardization of the study period. The APAC varies widely for different drainage basins, but the glaciers are in a state of rapid retreat, generally. According to the 14 meteorological stations in the Chinese Tianshan Mountains, both the temperature and precipitation display a marked increasing tendency from 1960 to 2009 at a rate of 0.34℃·(10a) −1 and 11 mm·(10a) −1 , respectively. The temperature in the dry seasons (from November to March) increases rapidly at a rate of 0.46℃·(10a) −1 , but the precipitation grows slowly at 2.3 mm·(10a) −1 . While the temperature in the wet seasons (from April to October) grows at a rate of 0.25 ·(10a) ℃ −1 , but the precipitation increases at 8.7 mm·(10a) −1 . The annual and seasonal climatic trends accelerate the retreat of glaciers.

Four new neo-clerodane diterpenoids, scutebarbatines W-Z (1-4), were isolated from the ethanol extract of Scutellaria barbata (Labiatae), and their structures were elucidated on the basis of extensive spectroscopic studies. In addition, the proposed structures of at least seven 13-spiro subtype neo-clerodanes: scutehenanine B (5), scutebarbatine G (6), 6-O-nicotinoylscutebarbatine G (7), barbatin A (8), 6,7-di-O-nicotinoylscutebarbatine G (9), 6-O-nicotinoyl-7-O-acetylscutebarbatine G (10), and scutebarbatine F (11), reported by Dai and co-workers from the same species, were incorrectly assigned and have been revised by reanalysis of the published NMR data.

Six new ent-pimarane diterpenoids, namely, ent-14beta,16-epoxy-8-pimarene-3beta,15alpha-diol (1), 7beta-hydroxydarutigenol (2), 9beta-hydroxydarutigenol (3), 16-O-acetyldarutigenol (4), 15,16-di-O-acetyldarutoside (5), and 16-O-acetyldarutoside (6), were isolated from the ethanol extract of Siegesbeckia orientalis. Their structures were elucidated on the basis of spectroscopic studies, and the absolute configuration of 1 was established by the modified Mosher's method. Furthermore, the structure of ent-12beta,16-epoxy-8-pimarene-2alpha,15beta,19-triol, recently isolated from the same plant, should be revised as ent-14beta,16-epoxy-8-pimarene-2alpha,15alpha,19-triol (10).

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