ISSN:
0170-2041
Keywords:
Teinemine and 22-isoteinemine
;
Etioline and 25-isoetioline
;
Solanum steroid alkaloids
;
Steroids
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The rare 16α-hydroxylated steroid alkaloids teinemine [(22S,25S)-22,26-epiminocholest-5-ene-3β,16α-diol, 8], 22-isoteinemine [(22R,25S)-22,26-epiminocholest-5-ene-3β,16α-diol, 10], etioline [(25S)-22,26-epiminocholesta-5,22(N)-diene-3β,16α-diol, 12], and 25-isoetioline [(25R)-22,26-epiminocholesta-5,22(N)-diene-3β,16α-diol, 21] are synthesized from the abundant spirosolane alkaloids tomatid-5-en-3β-ol [(25S)-22βN-spirosol-5-en-3β-ol, 1] and solasodine [(25R)-22αN-spirosol-5-en-3β-ol, 15], respectively. The crucial stages of these syntheses are the conversions of 1 or 15 into the N-protected (22S,25S)-, (22R,25S)-, and (22S,25R)-22,26-epimino-3β-hydroxycholest-5-en-16-ones 6, 7, and 18 as well as their reductions with sodium/ 2-propanol to the 16α-hydroxy compounds teinemine (8), 22-isoteinemine (10), and (22S,25R)-22,26-epiminocholest-5-ene-3β,16α-diol (19), respectively. By treatment with sodium methanolate the N-chloro derivatives 9 and 11 of 8 and 10 afford etioline (12). In an analogous manner, the N-chloro derivative 20 of 19 is converted into 25-isoetioline (21).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.199119910126
