Synthesis and structural determination of new brassinosteroid 24-nor-5α-cholane type analogs
Oyarce, Jocelyn (Universidad Técnica Federico Santa María. Departamento de Química. Chile)
Aitken, Vanesa (Universidad Técnica Federico Santa María. Departamento de Química. Chile)
González, César (Universidad Técnica Federico Santa María. Departamento de Química. Chile)
Ferrer, Karoll (Departamento de Química. Universidad Técnica Federico Santa María. Chile)
Olea, Andrés F. (Universidad Autónoma de Chile. Instituto de Ciencias Químicas Aplicadas)
Parella Coll, Teodor (Universitat Autònoma de Barcelona. Servei de Ressonància Magnètica Nuclear)
Espinoza Catalán, Luis (Universidad Técnica Federico Santa María. Departamento de Química. Chile)

Date:	2019
Abstract:	Natural brassinosteroids possess a 22R, 23R configuration that appears essential for biological activity. It is, therefore, interesting to elucidate if the activity of brassinosteroids with a short side chain depends on the C22 configuration. Herein, we describe the synthesis of new brassinosteroids analogs with 24-norcholane type of side chain and R configuration at C22. The initial reaction is the dihydroxylation of a terminal olefin that leads to S/R epimers. Three different methods were tested in order to evaluate the obtained S/R ratio and the reaction yields. The results indicate that Upjohn dihydroxylation is the most selective reaction giving a 1. 0:0. 24 S/R ratio, whereas a Sharpless reaction leads to a mixture of 1. 0:0. 90 S/R with 95% yield. Using the latter mixture and following a previous reported method, benzoylated derivatives and both S and R brassinosteroids analogs were synthesized. All synthesized compounds were completely characterized by NMR spectroscopy, and HRMS of new compounds are also given. In conclusion, a synthetic route for preparation of new analogs of brassinosteroids of 24-norcholane type and R configuration at C22 were described. It is expected that this will help to elucidate if a configuration at C22 is a structural requirement for hormonal growth activity in plants.
Grants:	Ministerio de Economía y Competitividad PGC2018-095808-B-I00
Rights:	Aquest document està subjecte a una llicència d'ús Creative Commons. Es permet la reproducció total o parcial, la distribució, la comunicació pública de l'obra i la creació d'obres derivades, fins i tot amb finalitats comercials, sempre i quan es reconegui l'autoria de l'obra original.
Language:	Anglès
Document:	Article ; recerca ; Versió publicada
Subject:	Synthesis ; Brassinosteroid ; Analogues ; 24-nor-5α-cholane
Published in:	Molecules, Vol. 24, Issue 24 (December 2019) , art. 4612, ISSN 1420-3049

DOI: 10.3390/molecules24244612
PMID: 31861056

14 p, 1.8 MB

The record appears in these collections:
Articles > Research articles
Articles > Published articles