GB1380253A - Prosapogenins - Google Patents

Abstract

1380253 Prosapogenins from Ruscus aculedtus INVERNI DELLA BEFFA SpA 21 Jan 1972 [21 Jan 1971] 2874/71 Heading C2U [Also in Division A5] Novel compounds which may be hydrolysed to ruscogenin or neoruscogenin are obtained by subjecting saponins of Ruscus aculeatus L. to partial hydrolysis, in particular enzymatic hydrolysis, resulting in removal of a glycosidic group attached to the 26-carbon atom of the saponin. The compounds are generally isolated in the form of mixtures known as "prosapogenins" which may be hydrolysed to form mixtures of ruscogenin and neoruscogenin. Particular components of certain of the prosapogenins have the formulae wherein R is one of the groups Preferably the hydrolysis is performed by dissolving or suspending the saponins in an aqueous solvent, e.g. water or a mixture of water and alcohol, acetone or dioxan, adding a waterimmiscible solvent e.g. ethyl acetate, treating with a pure #-glycosidase, a mixture of enzymes or an enzyme complex having #-glycosidasic activity, and effecting the hydrolysis at a temperature of 20-60‹ C. and at a pH of 4-8, the prosapogenins being recovered from the water-immiscible solvent. The crude prosapogenins obtained may be used as a raw material for obtaining partially purified prosapogenins, for the preparation of a number of pure prosapogenins and also as a raw material from which the components of the individual prosapogenins may be isolated. The isolated or chromatographically identified prosapogenins are (a) desgluconuscin (prosapogenin R6) which is a mixture of 1-O-[O-α-L-rhamnopyranosyl - (1#2) - α - L - arabinopyranosyl]- spirosta - 5(6),25(27) - diene - 1#,3# - diol (I) and 1 - O - [O - α - L - rhamnopyranosyl - (1#2)- α - L - arabinopyranosyl] - 25R - spirost - 5(6)- ene-1#,3#-diol (II), from which mixture (I) is obtained pure by acetylation of desglucoruscin, separation of the acetyl derivatives of ((I and (II) by crystallization and chromatography, and hydrolysis of the pure acetyl derivative of (I); (b) desglucodesrhamnoruscin (prosapogenin R9) which is identical with desglucoruscin but with a residue of rhamnose absent, and which may be formed by heating desglucoruscin with acetic acid and separated into its pure components in the same manner as (I) and (II) are separated; (c) ruscin (prosapogenin R4), which is a mixture of 1 - O - [O - # - D - glucopyranosyl - (1#3). O - α - L - rhamnopyranosyl - (1#2) - α - L- arabinopyranosyl] - spirosta - 5(6),25(27) - diene- 1#,3# - diol(V) and the corresponding 25R- spirost-5(6)-ene-1#,3#-diol (VI), which may again be separated in the same way as (I) and (II) are separated; and (d) four further prosapogenins designated R5, R3, R7 and R8. The novel compounds are useful in the treatment and prevention of circulatory disorders (see Heading A5B).