Solanidane alkaloids

The first naturally occurring 3/S-amino-solanidane alkaloid, solanogantine (C27H46N2O), has been isolated from S. giganteum 27 This non-crystalline base was... 

Thus all the natural solanidane alkaloids such as ruhijervine (II) and isorubijervine (III) are proved to possess 22R NS configuration 10). 

The structural features of the solanum alkaloids are based on two primary skeletal configurations solanidane, with or without glycoside functionalities, as featured by the toxic and teratogenic steroidal alkaloids a-chaconine and a-solanine with the indolizidine type E-F ring (Figure 2.7a) and the spirosolane... 

In other studies, solanidane-induced teratogenicity was proposed to depend upon C-22 configuration, c/Fig, (10), and the teratogenicity of epimeric solanidanes was suggested to correlate with the direction in which the unshared pair of electrons on the nitrogen atom projects relative to the steroidal plane [S2]. Earlier structure - terata relations of plant steroidal alkaloids have been summarized [S3]. 

Appendix) is graphically emphasized in Fig. (11) with values of the relative teratogenic potency of individual steroidal alkaloids from Table 2 placed adjacent to their structural type. The variance in values for the jervanes, solanidanes, and spirosolanes primarily reflects the level of saturation at C-5, C-6 e.g., 100 vs. 40 for jervanes, 32 vs. 9 for solanidanes, and 6 vs. 4 for spirosolanes. In each instance the higher value... 

Like rubijervine it has two hydroxyls, but in this case one is secondary and the other primary. It also has a basic tertiary nitrogen and one double bond. Aside from the different location of one of the hydroxyls, the two alkaloids display considerable similarity in their reactions. Although the direct relation of isorubijervine to a Solarium alkaloid has not been achieved, there is little doubt that it represents another isomer of hydroxysolanidine. In the following discussion the formula (XV) of Sato and Jacobs (58) will be used. In this formula the primary hydroxyl, which has as yet not been definitely located, is placed on C-18 of the solanidane skeleton. (See addendum on p. 312.)... 

Torres MCM, Jorge RJB, Ximenes RM, Alves NTQ, Santos JVD, Marinho AD, et al. Solanidane and iminosalanidane alkaloids from Solanum campaniforme. Phytochemistry 2013 % 457-64. 

Steroidal alkaloids of the Solanaceae can therefore be divided into two categories based on the aglycone the solanidine- and the solasodine-type alkaloids. The basic skeleton of the former alkaloids is known as solanidane, and that of the latter alkaloids is known as a spirosolane skeleton. 

Thus, the C27-steroid alkaloids with C-nor-D-homo [14(13->-12)-abeo] ring system, that is, with a jervane (5) or cevane (6) skeleton, found in Liliaceae but until now not in Solanaceae, are not included they will be described exhaustively in another chapter of this volume by S. M. Kupchan. On the other hand, the tertiary Veratrum bases rubijervine, isorubijervine, and veralobine belong to the solanidanes and will be mentioned briefly in this chapter, but a detailed description of these alkaloids and their derivatives will also be given by S. M. Kupchan. 

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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