Pregnane aglycone

Holacurtinol (40) is a minor alkaloid. The mass-spectrum showed fragments attributable to successive losses of two molecules of HjO suggesting the presence of two hydroxyl groups. The NMR spectral data showed the presence of the same sugar unit (4-deoxy-4-amino-P-D-cymaropyranose) as in 37 and 39, while the pregnane aglycone portion was similar to that of... 

Osladine aglycone (5) has been synthesized from solasodine via dihydrosolasodine A (6), the triformyl derivative (7), and isoverazine (8)/The pregnane derivative (9) has been prepared from N -acetylsolasodine. Single-crystal X-ray diffraction studies on solasodine monohydrate are in progress. ... 

From this edible vegetable we were able to isolate two new saponins named as caratuberside A(24) and caratuberside B (25). Their aglycones belong to pregnane series of steroids. 

Asterosaponin A a steroid saponin (see Sapo-nins). The aglycon is 3p,6a-dihydroxypregn-9(ll)-en-20-one, which contains a pregnane ring system (see Steroids), and which is linked to 2 molecules each of 6-deoxy-D-glucose and 6-deoxy-D-galactose, and one... 

Pregnane Type Sapogenins/Saponins. 5a-Pregn-16-en-3P-ol-20-one was isolated from Solanum pimpinellifolium Jussl. sub nom. Lycopersicon pimpinellifo-lium (Jussl.) Mill, by Schreiber and Aurich (1966) and also by Bennett et al. (1967). The authors speculated that this aglycone could be a metabolite of the steroidal glycoalkaloid tomatine. Heftmann and Schwimmer (1972) added that... 

Aglycones may be sterols of the classical type or, more often, pregnane and nor-pregnane derivatives, which are imcommon in the marine environment. Most of these sterosides are cytotoxic and inhibit the development of sea... 

For example, hapaioside, a glycoside of oor-pregnane isolated from Cribrochalina olemda (see Chapter 19) and glycosides of astrophorid sponges, whose aglycone is a triterpene (see Chapter 19). 

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