Two new spirostanol saponins, kingianoside I (1) and kingianoside K (2), corresponding to (3b,23S,25R)-23-hydroxy-12-oxospirost-5-en-3-yl 4-O-b-d-glucopyranosyl-b-d-galactopyranoside (1) and (3b,25R)-7-oxospirost-5-en-3-yl a-l-arabinofuranosyl-(1 ! 4)-[6-deoxy-a-l-mannopyranosyl-(1 ! 2)]-b-d-glucopyranoside (2), along with 13 known compounds, daucosterol, (25R)-kingianoside G, (25RS)-kingianoside A, pratioside D 1 , (25RS)-pratioside D 1 , (25S)-kingianoside C, kingianoside C, ginsenoside Rb 1 , saponins Tb and Pb, dioscin, gracillin, and saponin Pa, were isolated from the processed rhizomes of Polygonatum kingianum. The structures of the new compounds were elucidated by detailed spectroscopic analyses, including 1D-and 2D-NMR techniques, and chemical methods. Compound 2 contains a novel unusual spirostanol saponin aglycone. Ginsenoside Rb 1 and saponin Tb were isolated for the first time from the genus Polygonatum. The 13 known compounds were detected for the first time in the processed Polygonatum kingianum.Introduction. -The rhizomes of Polygonatum kingianum Coll. et Hemsl. (Liliaceae), one of the original plants commonly known as Huang-jing in traditional Chinese medicine, are used as a tonic remedy to treat lung troubles and ringworm [1]. Clinically, the processed (with yellow rice wine) products are routinely used since it is widely believed that this process would mitigate side-effects and enhance the effect of the tonic remedy.The chemical constituents of rhizomes of several Polygonatum species have been studied by several groups [2 -6], but no systematic study on the chemical constituents of the processed products has been reported so far. Previous phytochemical investigations on the fresh rhizomes of P. kingianum have resulted in the isolation of some steroidal saponins [7 -9]. Our preliminary phytochemical studies on processed P. kingianum indicated that the levels of certain steroidal saponins were higher in processed P. kingianum than those in fresh P. kingianum, whereas the levels of some other chemical constituents were decreased. In addition, the UPLC/MS profile of the processed P. kingianum revealed a few constituents that have not been reported before [10]. As a result, our detailed chemical investigation on steroidal saponins of the processed P. kingianum led to the isolation of two new steroidal saponins, along with 13 known compounds. Compound 2, kingianoside K, was found to possess a novel aglycone (with a C¼C bond at C(5) and an oxo group in the B ring on the aglycone)

The detailed NMR studies and full assignments of the 1H and 13C spectral data for two new furostanol saponins isolated from Agave sisalana leaves are described. Their structures were established using a combination of 1D and 2D NMR techniques including 1H, 13C, 1H-1H COSY, TOCSY, HSQC, HMBC and HSQC-TOCSY, and also FAB-MS spectrometry and chemical methods. The structures were established as (25S)-26-(beta-D-glucopyranosyl)-22 xi-hydroxyfurost-12-one-3beta-yl-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3)-O-[O-beta-D-glucopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl-(1-->4)-beta-D-galacto- pyranoside (1) and (25S)-26-(beta-D-glucopyranosyl)-22xi-hydroxyfurost-5-en-12-one-3beta-yl-O-alpha-L-rhamno- pyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->3)-O-[O-beta-D-glucopyranosyl-(1-->2)]-O-beta-D-glucopyranosyl- (1-->4)-beta-D-galactopyranoside (2).

A new furostanol saponin, sisalasaponin C (1), and a new spirostanol saponin, sisalasaponin D (2), were isolated from the fresh leaves of Agave sisalana, along with three other known steroidal saponins and two stilbenes. Their structures were identified as (3b,5a,6a,22a,25R)-3,26-bis (2), (3b,5a,6a,22a,25R)-22-methoxyfurostane-3,6,26-triyl tris-b-d-glucopyranoside, cantalasaponin-1, polianthoside D, (E)-and (Z)-2,3,4',5-tetrahydroxystilbene 2-O-b-d-glucopyranosides. The last three known compounds were isolated from the fresh leaves of Agavaceae for the first time. The structures of the new compounds were elucidated by detailed spectroscopic analysis, including 1D-and 2D-NMR experiments, and chemical techniques.

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