Sterols. LXXXVIII. Pregnanediols from Sarsasapogenin

Abstract

In a recent communication1 we reported the successful conversion of sarsasapogenin to pregnanediol-3(a),20(a). The fact that this transformation can be accomplished by simple reactions in good yields makes sarsasapogenin one of the cheapest and most practical sources of pregnane derivatives from which it is possible to prepare progesterone, testosterone and desoxycor-

A Simple Efficient Process for the Synthesis of 16-Dehydropregnenolone Acetate(16-Dpa)–A Key Steroid Drug Intermediate from Diosgenin

“…are synthesized from 16-dehydropregnenolone acetate (16-DPA) 1, barring a few which are obtained by total synthesis. The plant origin compounds solasodine 2 and its oxygen analogue diosgenin 3 ( Figure 1) are the two main ingredients from which 16-DPA is generally synthesized [4][5][6][7][8][9][10][11][12][13][14][15]. Due to the favorable climatic condition of North East region of India, diosgenin yielding dioscorea species of plants, viz., D. compositae and D. floribunda grow abundantly in the region which led us to investigate commercial exploitation of these plants through large scale production of 16-DPA starting from diosgenin.…”

“…Synthesis of 16-dehydropregnenolone acetate (16-DPA) 1 from solasodine 2 and diosgenin 3 has been reported by several workers in various literatures [4][5][6][7][8][9][10][11][12][13][14][15]. For the conversion of this spirostanic compound, diosgenin (22-iso-5-spirostane-3β-ol) into 16-DPA (3β-acetoxy-pregn-5,16-diene-20-one) 1, it must be isomerized first to furostenol derivative pseudodiosgenin diacetate (3β,26-diacetoxyfurosta-5,20(22)-diene) 4, through acetolysis (Figure 2), which on subsequent oxidation of the 20(22) enolic double bond followed by hydrolytic degradation furnishes 16-DPA [4][5][6][7][8][9][10][11][12][13][14][15].…”

“…For the conversion of this spirostanic compound, diosgenin (22-iso-5-spirostane-3β-ol) into 16-DPA (3β-acetoxy-pregn-5,16-diene-20-one) 1, it must be isomerized first to furostenol derivative pseudodiosgenin diacetate (3β,26-diacetoxyfurosta-5,20(22)-diene) 4, through acetolysis (Figure 2), which on subsequent oxidation of the 20(22) enolic double bond followed by hydrolytic degradation furnishes 16-DPA [4][5][6][7][8][9][10][11][12][13][14][15]. Chemical transformations of spirostanic compounds also find importance towards the synthesis of plant growth promoting substances including ecdysteroids and some furostenols having significant phytotoxicity [18].…”

“…Chemical transformations of spirostanic compounds also find importance towards the synthesis of plant growth promoting substances including ecdysteroids and some furostenols having significant phytotoxicity [18]. Marker's degradation is the earliest known process for converting diosgenin into 16-DPA [5][6][7].…”

Keto-Steroids, I Conversion of Diosgenin to 6 β-Methylpregn-4-ene-6 α,20-diol-3,16-dione

“…Diosgenin is converted by Marker degradation [1] to all types of adrenocortical and sex hormones through its transformation to the intermediate compound. pregna-5,16-diene-3/3-ol-20-one.…”