Spirosolan-3-ones

Spirosolan-3-one 3-Aminn-spirosnlanes 7.19 (deriv.) Two basic centres X S. hirsutum Dun. [syn. L. esculentum Mill, x L. hirsutum (Dun.) Macbride] ... 

Potato GAs usually belong to one of two structural types, either solanidanes or spirosolanes (Figure 14.3). Solanine and chaconine, both solanidanes, often comprise upwards of 90% of the total GA complement of domesticated potatoes, with chaconine often more abundant than solanine (Griffiths et al., 1997 Sotelo and Serrano, 2000). 

Solasodine (16a) is an important starting material for the preparation of 3/ -acetoxypregna-5,16-dien-20-one (17).18 Hydrogenation of the latter over Raney nickel gave the epimeric pregnenols (18a), which were converted (by standard reactions) into the amines (18b) and into the dimethylamino-pregnanes (19a) and (19b).17 The 3/ -amino-spirosolanes (20a), (20b), and (20c) have been prepared... 

The most significant chemical progress in the last 10 years is the finding that in addition to the long known alkaloids with spirosolane and solanidane skeleton there are a number of new ones which represent novel types of structure (II, IV, V). Extensive investigations have progressed further to establish the complete stereochemistry of the alkaloids as well as to confirm these statements by a number of new partial and total syntheses. 

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