Hecogenin steroids

The two major types of steroidal sapogenin are diosgenin and hecogenin. Steroidal saponins are used in the commercial production of sex hormones for clinical use. For example, progesterone is derived from diosgenin. 

Corbiere, C., Liagre, B., Bianchi, A., Bordji, K., Dauca, M., Netter, P. and Beneytout, J.L. (2003) Different contribution of apoptosis to the antiproliferative effects of diosgenin and other plant steroids, hecogenin and tigogenin, on human 1 547 osteosarcoma cells. International Journal of Oncology 22(4), 899-905. 

The addition of hydrogen to hindered ketones usually occurs preferentially from a less hindered side and the stereochemistry is less influenced by the nature of solvents than in the cases of unhindered ketones, as generalized in ASB rules 1 and 2. According to these rules, the axial alcohols are formed predominantly in the hydrogenation of hindered cyclohexanones under both acidic and neutral (or alkaline) conditions. The ABS rule, however, is oversimplified, as pointed out by Dauben et al.,180 since the addition of hydrogen from a less hindered side does not always give axial alcohols as in the cases of 5a-cholestan-l-one (28)181 and the 12-oxo steroid 29 (hecogenin),182 where... 

The seminal work on steroid analyses using chiroptical detection was done by Djerrasi by the determination of hecogenin acetate in the presence of tigonenin acetate.Every steroid is chiral and therefore amenable to polarimetric detection after chromatographic separation. Chromophores are fairly uncommon, and analysis by ORD or CD is therefore less suitable. The only unsaturation in the cholesterol molecule, for example, is the isolated A -double bond, which has an absorbance maximum at 205 nm. Unsaturation coupled with chirality provides some selectivity, as ably demonstrated by the work of Potapov for analogs of progesterone Even simpler than that is the direct discrimination between the ketosteroids testosterone and dihydrotestosterone, which have opposite signs in methylene chloride solution (Fig. 6). 

HECOGENIN Hecogenin is a steroidal sapogenin, which can be obtained from the waste juice from the preparation of sisal from the leaves of A a-ve sisalana (Engelm.)... 

The press juice is fermented in open barrels, and air is blown through the juice. 0.5% phenol is added to precipitate the crude hecogenin, which is filtered and dried and sent to the steroid factory, where the existing keto-group in the 12-position can be transferred via bromination to the 11-position... 

Due to the common occurrence of steroids in Nature, there is not much need to synthesize the steroid skeleton from simple substrates. Therefore, the use of phosphonates in syntheses involving this class of compounds, concerns mostly modifications of the steroid pool, like in the case of the conversion of 17-oxo-steroids to 20-ketosteroids and progesterone as well as construction of the South steroid subunit of cephalostatin 1 from hecogenin acetate. 

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