A new clerodane-type diterpenoid lactone, scuterivulactone D, has been isolated from the whole plants of Scutellaria rivularis Wall. and the structure has been determined by means of 2-D NMR spectroscopy including the 1H-13C long-range shift correlation spectrum.
An antitumor morphinane alkaloid named sinococuline was isolated from the MeOH extract of Cocculus trilobus. Its structure was determined by spectroscopic analysis.
When (2-aminoalkoxy) trimethylsilane is activated by two intramolecular heteroatoms (oxygen and nitrogen), it undergoes metallation efficiently with t-butyllithium to yield α-silyl carbanion. This process is applicable to carbonyl methylenations.
The synthesis of 5-fluoroarachidonic acid (1) was achieved from the intermediate (E) -5, 6-dihydroxy-2-fluorohex-2-enoate 5, 6-acetonide (5). Incubation of 1 with human platelets yielded 5-fluoro-12-hydroxyeicosatetraenoic acid (5F-12-HETE, 2).
The structures of four new isoatisine-type alkaloids, spiramines A, B, C, and D, isolated from Spiraea japonica L. fil var acuminata Franch, were determined.