GB1251740A - - Google Patents

Abstract

1,251,740. 22,23-Secosolanidanes. OSTERREICHISCHE STICKSTOFFWERKE A.G. 19 Dec., 1969 [27 Dec., 1968; 10 Feb., 1969], No. 62149/69. Heading C2U Novel compounds of Formula I (wherein X-Y represents a single bond (with 5α-H or 5#-H) or a double bond and A represents a carbonyl, dialkoxymethylene, alkylenedioxymethylene or α- or #-hydroxymethylene group and wherein a A<SP>4</SP>-double bond may be present when X-Y is a single bond and A is carbonyl, dialkoxymethylene or alkylenedioxymethylene) are prepared from compounds of Formula II or IV (wherein X-Y is as defined above, A<SP>1</SP> is as defined for A or can be α- or #-acyloxy-methylene, X- 1 is the anion of an organic or inorganic acid, and wherein a #<SP>4</SP>-double bond may be present as in Formula I) by oxidation with chromium trioxide and a tertiary heterocyclic base to give a compound of formula and, after converting any 3-oxo group in the latter to a dialkoxy or alkylenedioxy group, reducing these intermediates with a simple or complex alkali metal or alkaline earth metal hydride, and, when required hydrolysing any ketalized 3-oxo group in the product, Compounds II may be employed in admixture with the corresponding 22,23-saturated-16α-hydroxy compounds (VI), and compounds IV may be employed in admixture with the corresponding #<SP>16(N)</SP>-isomers (V). The oxidation reaction also oxidizes a 3-hydroxy group to an oxo group if no #<SP>5</SP>-double bond is present and may, if desired, be preceded by protective acylation of such a group. A 3-acyloxy group in compounds III is converted to a hydroxy group either during the aforesaid reduction reaction or in a previously performed hydrolysis step. Ketalization of 3-oxo compounds III is effected with alkanols or alkanediols and is accompanied by isomerization of any #<SP>4</SP>-double bond present to a #<SP>5</SP>-double bond and, possibly, by esterification of the carboxy group. Compounds II and IV are described in Specification 1,226,503. Compounds V and VI are described in Specification 1,215,258.