782494-69-3

Upstream product

• 145-13-1 Pregnenolone 
• 782494-67-1 (20R,22R)-3β-(tert-butyldimethylsilyl)oxycholest-5-ene-20,22-diol 
• 782494-65-9 (20R,22R,23R)-22,23-epoxy-3β-(tert-butyldimethylsilyl)oxycholest-5-en-20-ol 
• 782494-64-8 (20R,22Z)-3β-(tert-butyldimethylsilyl)oxycholesta-5,22-dien-20-ol 
• 115910-64-0 (20R)-3β-(tert-butyldimethylsilyl)oxycholest-5-en-22-yn-20-ol 
• 58701-45-4 3β-t-butyldimethylsilyloxy-pregn-5-en-20-one 
• 98-59-9 p-toluenesulfonyl chloride 
• 782494-68-2 (20R,22R)-20,22-isopropylidenedioxycholest-5-ene-3β-ol 
• 7154-75-8 4-methylpentyne 

Downstream Products

• 782494-70-6 Toluene-4-sulfonic acid (3S,5S,6S,8R,9S,10R,13S,14S,17S)-6-hydroxy-10,13-dimethyl-17-[(4R,5R)-2,2,4-trimethyl-5-(3-methyl-butyl)-[1,3]dioxolan-4-yl]-hexadecahydro-cyclopenta[a]phenanthren-3-yl ester 

Relevant academic research and scientific papers

Synthesis of ponasterone A derivatives with various steroid skeleton moieties and evaluation of their binding to the ecdysone receptor of Kc cells

A series of ponasterone A (PNA) derivatives with various steroid moieties were synthesized to measure their binding activity to the ecdysone receptors of Drosophila Kc cells. The activity of compounds was evaluated by determining the concentration required to give the 50% inhibition (IC50 in M) of the incorporation of [3H]PNA to Drosophila Kc cells. Compounds with no functional groups such as OH and C{double bond, long}O group in the steroid skeleton moiety were inactive. By the introduction of functional groups such as the OH and the C{double bond, long}O group in the steroidal structure, these compounds became active. Some compounds containing the A/B-trans ring fusion, which is different from that (A/B-cis) of ecdysteroids were also active. The oxidation of CH2 at 6-position to C{double bond, long}O, enhanced the activity 19 times, but the activity was erased by the reduction of oxo to OH group at 6-position. The activity was enhanced about 250 times by the conversion of A/B ring configuration from trans [(20R,22R)-2β,3β,20,22-tetrahydroxy-5α-cholestan-6-one: pIC50 = 4.84] to cis [(20R,22R)-2β,3β,20,22-tetrahydroxy-5β-cholestan-6-one: pIC50 = 7.23]. The latter cis-type compound which is the most potent among compounds synthesized in this study was equipotent to the natural molting hormone, 20-hydroxyecdysone, even though it is 1/50 of PNA.

Stereoselective synthesis of (22R)- and (22S)-castasterone/ponasterone a hybrid compounds and evaluation of their molting hormone activity

Two stereoisomers of a castasterone/ponasterone A hybrid compound, the (20R,22R) and (20R,22S)-isomers of 2α,3α,20,22-tetrahydroxy- 5α-cholestan-6-one, were synthesized stereoselectively and their binding activity to the ecdysteroid receptor was determined. From the concentration-response curve for the inhibition of the incorporation of tritiated ponasterone A into ecdysteroid receptor containing insect cells, the concentration (IC50) required to inhibit 50% of the incorporation of radioactivity into cells was evaluated. The IC50 values of the (22R)- and (22S)-isomers were determined to be 0.30 and 38.9 μM against Kc cells, respectively, indicating that the (22R)-isomer is about 100 times more potent than the corresponding (22S)-isomer. IC50 values of these compounds against lepidopteran Sf-9 cells were determined to be 0.36 and 12.9 μM, respectively. The molting hormonal effect was examined in a Chilo suppressalis integument system and the 50% effective concentration for the stimulation of N-acetylglucosamine incorporation into the cultured integument was determined to be 2.7 μM for the (22R)-isomer, while the (22S)-isomer was inactive. On the other hand, both isomers did not show brassinolide-like activity in the rice lamina inclination assay.