In a general survey on the seed-sa:ogenins of Camellia species, we have isolated from Camellia japonica L. three sapogenins, camelliagenin A, B, and C and established their structures as Ia, Ib and Ic, respectively (1). On the sapogenins of the other Japanese species of this genus, 2. sinensis 0. Kuntze (Thea sinensis L.) and 2. Sasanqua Thunb., only little was known (2,3) until the recent publications (4) by Yoshioka and his coworkers on the isolation and structure determination of two major sapogenins, theasapogenol A (IIa) and B (IIb) obtained from the seeds of the former plant. This paper prompted US to record the results of our investigation on the seed-sapogenins of both plants mentioned above and to present evidence for the assignment of structures III and XVII for the two new sapogenins, oamelliagenin D and E, isolated from both plants.
Ueda's method of isolation (3) followed by a silica gel chromatography afforded eight sapogenins (shown in Table ) from each Plant (5). Five of the sapogenins were found to be identical with Ia, Ib, Ic, IIa and IIb ( )s and all of our results from preliminary erperiments on the last two are compatible with the structures proposed (4,7).