19338-77-3Relevant academic research and scientific papers
Efficient synthesis of ponasterone A by recombinant Escherichia coli harboring the glycosyltransferase GTBP1 with in situ product removal
Li, Bingfeng,He, Xuejun,Fan, Bo,Chu, Jianlin,He, Bingfang
, p. 23027 - 23029 (2017/07/10)
A glycosyltransferase GTBP1 from Bacillus pumilus BF1 was isolated. Efficient production of ponasterone A was achieved by the recombinant E. coli/gtBP1 in a biphasic system with a molar yield of 92.7%. This in situ product removal provided the driving force for shifting the reaction equilibrium towards the synthesis of the product.
Dimeric ecdysteroid analogues and their interaction with the Drosophila ecdysteroid receptor
Harmatha, Juraj,Budesinsky, Milos,Vokac, Karel,Dinan, Laurence,Lafont, Rene
, p. 1229 - 1238 (2008/03/28)
Three structurally related specific ecdysteroid derivatives, 7,7′-dimers of 14-deoxy-8(14)-ene transformed 20-hydroxyecdysone, ponasterone A and ajugasterone C, were obtained by photochemical transformation. The structures of the dimeric ecdysteroids were identified mainly by NMR spectroscopy supported by MS and IR spectroscopy. Yields of the dimerisation products were dependent on the reactant concentrations and photoreaction conditions. Inert gas atmosphere supported high yields, whereas oxygen atmosphere fully prevented the dimer formation. All the three dimers retained a rather high agonistic activity at the ecdysteroid receptor in the Drosophila BII bioassay when compared with the relevant original ecdysteroids.
C-25 epimeric 26-haloponasterone A: Synthesis, absolute configuration and moulting activity
Yingyongnarongkul, Boon-Ek,Kumpun, Saowanee,Chimnoi, Nitirat
, p. 636 - 644 (2007/10/03)
A convenient synthesis of inokosterone has been accomplished. Inokosterone exists as two C-25 epimers, which could be separated from each other through their diacetonide derivatives. The absolute configuration of these compounds was determined. Two C-25 epimers of 26-chloroponasterone A were synthesized from the respective C-25 epimeric inokosterone. Two epimeric 26-bromo and 26-iodoponasterone A compounds were also synthesized. Moulting activity of these compounds was evaluated using the Musca bioassay, and it was found that the (25S)-26-halo analogues were more active than the corresponding (25R)-26-halo analogues. Among the 25S series, an increase in activity with an increase in size of the halogen atom was observed, indicating that the steric factor was more important than the electronic factor in binding of these ecdysteroid analogues to the receptor. On the other hand, a decrease in activity with an increase in size of the halogen atom was noted in the 25R series, suggesting that the steric factor was less important than the electronic factor. The results indicated that the configuration at C-25 and the substituent at C-26 have significant influences on the interaction of ecdysteroids with their receptor.
Stereoselective catalytic hydrogenation of Δ7-6-ketosteroids in the presence of sodium nitrite
Suksamrarn, Apichart,Tanachatchairatana, Tanud,Sirigarn, Chana
, p. 6033 - 6037 (2007/10/03)
Catalytic hydrogenation with Pd-C as a catalyst in the presence of sodium nitrite is a simple, convenient and high yielding stereoselective reduction of olefinic function of Δ7-6-ketosteroids to the corresponding dihydro analogues.
Ozonolysis of alkenes and study of reactions of polyfunctional compounds: LXVI. Ozonolysis and hydrogenation of diacetonides of 24,25- and 25,26-anhydro-20-hydroxyecdysones. Synthesis of ponasterone A
Odinokov,Savchenko,Nazmeeva,Galyautdinov,Khalilov
, p. 525 - 529 (2007/10/03)
Ozonolysis of 2,3:20,22-diacetonides of 24.25-and 25,26-anhydro-20-hydroxyecdysones afforded the corresponding ω-carbonyl derivatives. The hydrogenation of the mentioned dehydration products of 20-hydroxyecdysone acetonide yielded diacetonide of ponasterone A that provided ponasterone A and its 29,22-acetonide at hydrolysis.
