Omithopus sativus

Metabolism of 24-epicastasterone and 24-epibrassinolide in cultured cells of tomato and Omithopus sativus 

24- epicastasterone. However, glucosylation of 24-epibrassinolide itself has not been found. 

Overall, epimerization of the 3a-hydroxyl and/or introduction of a hydroxyl group at C25 and C26 is critical for the metabolism of 24-epicastasterone and 24-epibrassinolide in tomato cells. In the rice lamina inclination assay, 25-hydroxy-24-epibrassinolide is tenfold more active than 24-epibrassinolide, but 26-hydroxy-24-epibrassinolide is less active. However, 25-hydroxy-24-epibrassinolide is hundred-fold less active in restoring the dwarf phenotype of the BR-deficient Arabidopsis mutants [72], Therefore, although the 

25- hydroxylation has been shown to be an important activation step in the biosynthesis of ecdysone and vitamin D3, this may not be the case in plants. The C25-hydroxylation is 

In Omithopus sativus cells, a to p epimerization of the 3-hydroxyl is quite important in the metabolism of 24-epicastasterone (Fig. 5) and 24-epibrassinolide (Fig. 6) because all the metabolites have a 3p-hydroxyl group [74-76], Thus 3,24-diepicastasterone is formed first and then metabolized through two different pathways which are not observed in tomato cells (Fig. 5). One is the acylation of the C3p-hydroxyl leading to a mixture of 

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Omithopus sativus (seed, shoots) Leguminosae Castasterone (3), 6-Deoxocastasterone (10), 24-Epicastasterone (13), 6-Deoxo-24-epicastasterone (33), 6-Deoxo-28-norcastasterone (34) 47,48... 

Two new brassinosteroids could be detected from the shoots of Omithopus sativus (see. Section 2). One of them, 6-deoxo-24-epicastasterone (33), was synthesized by us from 24-epicastasterone (13) via the corresponding thioacetal 70 and subsequent reductive elimination of the thioketal group by reaction with tri-n-butyltin hydride (BujSnH) in the presence of 2,2 -azabis-2 -methylpropionitrile (A1BN) (Scheme 8).48... 

Ri Cholesterol (C27) pY k°" 28-Nurcastasterone VsY Rs 28-Norbrassinolide Zea mays llen) [21] Omithopus sativus ( oot)f22] Lycopercicon esculentim (shoot) [23] (10 species)... 

Fig. 5. Metabolism of 24-epicastasterone in the cultured cells of tomato and Omithopus sativus. Identified as a glycoside(s) in tomato cells Identified as the free form in Omithopus cells...

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