51576-10-4Relevant academic research and scientific papers
SYNTHESIS OF GIBBERELLINS FROM STEVIOL USING THE FUNGUS GIBBERELLA FUJIKUROI
Gianfagna, Thomas,Zeevaart, Jan A. D.,Lusk, William J.
, p. 427 - 430 (1983)
Steviol (ent-13-hydroxykaur-16-en-19-oic acid) was synthesized from steviol acetate norketone (ent-13-acetoxy-16-oxo-17-norkauran-19-oic acid) by the Wittig reaction using (methyl-d3)triphenylphosphonium bromide.A mixture of steviol analogs was produced containing from one to four 2H/molecule. Steviol was fed to strain LM-45-399 the fungus Gibberella fujikuroi which was grown on synthetic medium (ICI, 0percent N) in the presence of the growth retardant CCC. GA1, GA18, GA23 and GA53 were isolated from the fungal medium after 4 days.This strain converted steviol to 13-hydroxy GAs in the highest yields of the four Gibberella strains tested, and in amounts suitable for metabolic studies with higher plants. Key Word Index - Gibberella fujikuroi; fungi; gibberellin biosynthesis; 2H-labelled; GC/MS; GA1; GA18; GA23; GA53; steviol.
Synthetic study on the relationship between structure and sweet taste properties of steviol glycosides
Upreti, Mani,Dubois, Grant,Prakash, Indra
, p. 4186 - 4196 (2012)
The structure activity relationship between the C16-C 17 methylene double bond on the aglycone of steviol glycosides and the corresponding impact on their sweet taste has been reported here for the first time. It has been observed that converting stevioside and rebaudioside A to their corresponding ketones by switching the doubly bonded methylene on C-17 for a ketone group actually removes the sweet taste properties of these molecules completely. Regenerating the original molecules tends to restore the sweet taste of both the steviol glycosides. Thus this C16-C 17 methylene double bond in rebaudioside A and stevioside can be regarded as a pharmacophore essential for the sweetness property of these molecules.
Synthesis and biological evaluation of novel exo-methylene cyclopentanone tetracyclic diterpenoids as antitumor agents
Li, Jing,Zhang, Dayong,Wu, Xiaoming
supporting information; experimental part, p. 130 - 132 (2011/02/28)
The structure of exo-methylene cyclopentanone, which exists in nature tetracyclic diterpenoids products, has been proved to be an innate group for the treatment of cancer and inflammation. In this letter, four different scaffolds of tetracyclic diterpenoi
Synthesis of ent-kaurane diterpene monoglycosides
Chaturvedula, Venkata Sai Prakash,Klucik, Josef,Upreti, Mani,Prakash, Indra
scheme or table, p. 8402 - 8409 (2011/12/15)
Synthesis of two ent-kaurane diterpene glycosides, steviol 19-O-β-D-glucopyranosiduronic acid (steviol glucuronide, 5), and 13-hydroxy ent-kaur-16-en-19-oic acid-β-D-glucopyranosyl ester (7) has been achieved from a common starting material, steviol, usin
GIBBERELLINS IN SEEDS OF HELIANTHUS ANNUUS
Hutchison, Michael,Gaskin, Paul,MacMillan, Jake,Phinney, Bernard O.
, p. 2695 - 2702 (2007/10/02)
Fourteen gibberellins (GAs) have been identified in seeds of Helianthus annuus.They comprise the previously known GA1, GA4, GA19, GA20 and GA45 and nine new 15β-hydroxyGAs.Of the new GAs, 15β-hydroxyGA20 and 15β-hydroxyGA1 have been previously synthesized chemically from GA3 and are now assigned the numbers GA67 and GA72.The structures of 15β-hydroxyGA15, 15β-hydroxyGA24 and 15β-hydroxyGA25 were established by their formation from the incubation of ent-15α-hydroxykaur-16-en-19-oic acid with cultures of Gibberella fujikuroi, mutant B1-41a; these new Gas have been respectively assigned the numbers, GA64, GA65 and GA66.The remaining four GAs have been tentatively assigned the structures, 15β-hydroxyGA17, 15β-hydroxyGA19, 15β-hydroxyGA44 and 15β-hydroxyGA53 on the basis of the mass spectra of their MeTMSi derivatives.Abscisic acid, trans-abscisic acid, dihydrophaseic acid, dioxindole-3-acetic acid, ent-7α,16α,17-trihydroxy-16αH-kauranoic acid and ent-7α,16β,17-trihydroxy-and ent-6α,7α,16β,17-tetrahydroxy-16βH-kauranoic acids have also been detected in seeds of Helianthus annuus by capillary GC-MS.From the incubation of ent-15α-hydroxykaur-16-en-19-oic acid with Gibberella fujikuroi, mutant B1-41a, ent-7α,15α-dihydroxykaur-16-en-19-oic acid and 7β,15β-dihydroxykaurenolide have been isolated.Key Word Index - Helianthus annuus; Compositae; sunflower; native gibberellins; new 15β-hydroxygibberellins; microbiological conversion of ent-15α-hydroxykaur-16-en-19-oic acid; Gibberella fujikuroi; mutant B1-41a.
Metabolism of Steviol and Its Derivatives by Gibberella fujikuroi
Murofushi, Noboru,Shigematsu, Yoshio,Nagura, Shigehiro,Takahashi, Nobutaka
, p. 2305 - 2312 (2007/10/02)
Steviol (ent-13-hydroxykaur-16-en-19-oic acid is metabolized by Gibberella fujikuroi in the presence of inhibitors of gibberellin biosynthesis, such as quaternary ammonium salt-type growth retardants, to afford 7β-hydroxy- and 6β,7β-dihydroxysteviol, gibberellins A1, A18, A19, A53 and 7β,13-dihydroxykaurenolide.Steviol acetate (ent-13-acetoxykaur-16-en-19-oic acid) is also metabolized to the 6β,7β-dihydroxy-derivative and to the 13-acetyl derivatives of gibberellins A17 and A20 and steviol methyl ester (methyl ent-13-hydroxykaur-16-en-19-oate) into the monohydroxy-, dihydroxy- and hydroxyoxo-derivatives.These results indicate a low substrate specificity of the enzymes in the fungus and provide a useful preparative methodology of several important plant gibberellins carrying the 13-hydroxyl group.
