ASSTRACT.-A new molluscicidal spirostanol glycoside has been isolated from an EtOH extract of the inflorescence of Yucca alogolia and characterized as 3-O-[a-~-rhamnopyranosyl ( 1~3>a-~-arabinopyranosyl( 1~3)-~-~-xylopyranosy1( 1~3>~-~-glucopyranosyl)-2 5R, 5a-spirostan-2a,3~diol[l] with the help of fabms and 'H-and "C-nmr spectra. Yurca aloifoolia L. (Agavaceae) is an ornamental plant, and many steroidal sapogenins have been reported from it (1-3). A literature survey showed that no phytochemical work has been reported from the inflorescence of this plant. Here, we report a new spirostanol glycoside from the EtOH extract of the inflorescence of this plant. obtained from the inflorescence of Y. aloifolia afforded compound 1. Its ir spectrum showed absorptions at 981, 926, 901, and 864 cm-' (spiroketal moiety), with the absorption at 901 cm-' being of greater intensity than at 926 cm-' which is characteristic of the 25R stereochemistry (4). Acidic hydrolysis furnished gitogenin and D-glucose, D-xylOSe, L-arabinose, and L-rhamnose (pc). A mol wt of 1004 was established by the appearance of [MI+ in the fabms, Repeated cc of the saponin mixture I OH / and peaks at 858 {M -146(deoxyhexose -H20)7+, 726 {M -(146 + 132)]+, 594 [M -(146 + 132 + 132)]+, and 432 & I -(146 + 132 + 132 + 162)1+ indicated the sugar sequence to be deoxyhexosyl-pentosyl-pentosyl-hexosyl-gitogenin. Interglycosidation points were elucidated by the permethylation studies. The permethylate was obtained by Hakomori's method ( 5 ) and on hydrolysis afforded 2,3,4-tri-O-rnethyl-~-rhamnose, 2,4-di-0-methyl-L-arabinose, 2,4di-O-rnethyl-~-xylose, and 2,4,6-tri-O-methyl-~glu-cose. Partial hydrolysis of 1 afforded gitogenin and prosapogenins PS PS,, and PS,. Confirmation of the glycoside sequence was obtained by the hydrolysis of permethylates of these prosapogenins. The permethylate of PSI on hydrolysis gave 2,3,4,6-tetra-O-methyl-~-glucose; PS, afforded 2,4,6-tri-O-methyl-D-glucose and 2,3,4,-tri-O-methyl-D-0 w H O W OH