Labdane diterpenes from an acacia species

Five New Diterpenoids, Viteagnusins A-E, from the Fruit of Vitex agnus-castus

“…Furthermore, the 13 C-NMR data of 3 were different from those of 9 and the 13-epimer of 9. 20) Consequently, the structure of 3 was concluded to be (rel 5S,8R,9S,10S)-8,13-dihydroxy-14-labden (Fig. 1).…”

Ptychantins from the Liverwort Ptychanthus Striatus

“…Likewise, the 13 C NMR data of C-13 and C-8 at d C 72.2 and 72.6 ( Tables 1 and 2), while only two acetoxyl groups observed. The HMBC and NOESY spectra again provided clues for the acetoxyl groups at C-1 and C-11 and hydroxyl groups at C-6 and C-7.…”

“…Again the identity to ptychantin I was confirmed by comparisons with authentic spectra. 10 Since the NMR spectral data of both ptychantins G and I were not reported in the literature, their 13 C NMR data were compiled in The IR spectrum of 8 showed the presence of a hydroxyl group (n max 3438 cm -1 ) which was placed at C-3 according to the subsequent HMBC measurement. The assignment of the other three acetoxyl groups at C-1, C-6 and C-11 were also deduced from HMBC experiment.…”

Two Labdane Diterpene and Megastigmane Glycosides from Aquilegia hybrida

“…2). Meanwhile, the B ring and the side chain of the aglycon moiety were superimposable on that of sclareol 9) (13S-type) or 13-epi-sclareol 9) (13R-type). A comparative study of the 13 C-NMR (CDCl 3 , Table 1) spectrum of 1 with that of sclareol (13S-type) revealed identical signals due to C-13, C-14, C-15, and C-16 on the side chain.…”