From the leaves of Flindersia bourjotinna F. Muell. there were isolated sitosterol, triacontanol, lupeol, germanicol, germanicone, and four new triterpenoids, the bourjotinolones A, B, and C, and bourjotone. By chemical degradation and spectroscopic methods, the structures of these substances were shown to be 21,24-epoxy-23,25-dihydroxytirucall-7-en-3one, 23,24-dihydroxytirucalla-7,25-dien- 3-one, 25-chloro-23,24-dihydroxytirucall-7-en-3-one, and 25,26,27-trisnortirucall-7- ene-3,23-dione, respectively. Bourjotinolone C is almost certainly an artefact but bourjotinolone B and bourjotone are less likely to be. From biogenetic and N.M.R. spectral considerations, the absolute stereochemistry of the new triterpenes may be deduced.
The preparation of 3α,12α-bisdimethylamino-5β-cholane dimethiodide, 3α,12α-bisdimethylamino-5β-cholane dimethiodide, 3α,12α- bisdimethylamino-24-nor-5β-cholanedimethiodide, and 3α,12α- bisdimethylamino-24-nor-5β-cholanediethiodide, from deoxycholic acid are described. During this work it was found that attempted copper- quinoline decarboxylation of dehydrocholic acid gives rise to lactol formation, and that what had previously been considered to be 3α,12α- dihydroxy-5β-cholane is a mixture of this compound and 12α,24- dihydroxy-5β-cholane. Comparable selectivity of attack by methanesulphonyl chloride and toluene-p-sulphonyl chloride occurs with various polyhydric alcohols derived from bile acids, as evidenced from the products of reduction of the sulphonates with lithium aluminium hydride. With both 5α- and 5β-cholane derivatives, a C 3 equatorial hydroxyl group exhibits comparable reactivity to the terminal primary hydroxyl group, generated from the bile acid carboxylic group, towards both sulphonyl chlorides. With axial hydroxyl groups at C 7 and C 12, toluene-p-sulphonate formation is much more difficult than methane- sulphonate formation. Reduction by means of lithium aluminium hydride of equatorial sulphonate esters at C 7 and C 12 gives rise to a methylene group, but the axial sulphonates under the same conditions give the axial alcohol. The same clear distinction between equatorial and axial sulphonate esters is not observed at C 3 and C 6, but 17α- methanesulphonyloxy-5α-androstane gives 5α-androstane and the 17β- ester gives 17β-hydroxy-5α-androstane. Reduction of 12-oximino groups in both 5α- and 5β-cholanes with sodium and ethanol, hydrogen in the presence of a catalyst, or lithium aluminium hydride gives solely the 12α-amino compound.
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