The chemistry and biochemistry of Spiraea japonica complex.

The characteristic components of Spiraea japonica complex, which consists of seven varieties, are the hetisine- and atisine-type diterpene alkaloids, and the atisane-type diterpenes. From this complex, 20 hetisines, 37 atisines and 7 diterpenes were isolated during 1964-2001, including the observations of the isomerization of spiraea diterpene alkaloids having the oxazolidine ring and the interconversion of the oxazolidine rings, the configuration of the oxygen substitution at C-15 of the atisine-type alkaloids, and the interconversion relationship between the two main subtypes of the hetisine-type alkaloids. The chemotaxonomy based on structures of the reported diterpene alkaloids were suggested. The studies on the anti-inflammation, anti-platelet aggregation and neuroprotective bioactivities of the alkaloids from S. japonica var. acuta were reviewed as well.