Brassinolide-like activity of castasterone analogs with varied side chains against rice lamina inclination. Issue 17 (1st September 2017)

• Record Type: Journal Article
• Authors: Watanabe, Bunta; Yamamoto, Shuji; Yokoi, Taiyo; Sugiura, Airi; Horoiwa, Shinri; Aoki, Takanori; Miyagawa, Hisashi; Nakagawa, Yoshiaki
• Is Part Of: Bioorganic & medicinal chemistry. Volume 25:Issue 17(2017)
• Page Start: 4566
• Page End: 4578
• Publication Date: 2017-09-01
• Subjects: BL brassinolide -- BRI1 brassinosteroid-insensitive 1 -- CS castasterone -- ESI electrospray ionization -- Ms methanesulfonyl -- rt room temperature -- MM-PBSA Molecular Mechanics Poisson-Boltzmann Surface Area; Brassinolide -- Castasterone -- Brassinosteroid -- Rice lamina inclination -- Oryza sativa -- Molecular dynamics; Bioorganic chemistry -- Periodicals; Pharmaceutical chemistry -- Periodicals; Biochemistry -- Periodicals; Chemistry, Clinical -- Periodicals; Chemistry, Organic -- Periodicals; Chimie bio-organique -- Périodiques; Chimie pharmaceutique -- Périodiques; 615.19
• DOI: 10.1016/j.bmc.2017.06.012
• Languages: English
• ISSNs: 0968-0896

Abstract

Graphical abstract: Abstract: Brassinolide (BL) and castasterone (CS) are the representative members of brassinosteroid class of plant steroid hormone having plant growth promoting activity. In this study, eleven CS analogs bearing a variety of side chains were synthesized to determine the effect of the side chain structures on the BL-like activity. The plant hormonal activity was evaluated in a dwarf rice lamina inclination assay, and the potency was determined as the reciprocal logarithm of the 50% effective dose (ED50 ) from each dose-response curve. The reciprocal logarithm of ED50 (pED50 ) was decreased dramatically upon deletion of the C-28 methyl group of CS. The introduction of oxygen-containing groups such as hydroxy, methoxy, and ethoxycarbonyl was also unfavorable to the activity. The pED50 was influenced by the geometry of carbon-carbon double bond between C-24 and C-25 ( cis and trans ), but the introduction of a fluorine atom at the C-25 position of the double bond did not significantly change the activity. The binding free energy (Δ G ) was calculated for all ligand–receptor binding interactions using molecular dynamics, resulting that Δ G is linearly correlated with the pED50 .