title: Synthesis and bioactivity evaluation of brassinosteroid analogs.
abstract: Four new analogs of 28-homocastasterone have been synthesized and completely characterized for the first time from stigmasterol. (22R, 23R,24S)-3beta-acetoxy-22,23-dihydroxy-5alpha-stigmastan+ ++-6-one (17), (22R,23R,24S)-3beta-bromo-22,23-dihydroxy-5alpha-stigmast an-6-one (18), (22R,23R,24S)-3beta-acetoxy-5,22, 23-trihydroxy-5alpha-stigmastan-6-one (20), and (22R,23R, 24S)-3beta-bromo-5,22,23-trihydroxy-5alpha-stigmastan-6-one (21), were obtained through a synthetic route based on regioselective Delta(5) epoxidation. Compounds 17 and 18, bearing a 5alphaH moiety, were prepared through a reductive opening of the 5beta,6beta epoxy precursor, and compounds 20 and 21, analogs with a 5alphaOH moiety were obtained by hydrolytic opening of a mixture of 5alpha,6alpha and 5beta,6beta epoxy precursors. Known compounds 19 and 22 were also obtained following the described synthetic routes, respectively. The new compounds were tested with the traditional auxin-like bioassay for brassinosteroids with 19 and 22 as standards. All compounds were comparatively evaluated for their inhibitory effect on the replication of DNA (HSV-1) virus.
authors.affiliation: Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria 1428, Buenos Aires, Argentina.
authors.forename: J A
authors.initials: JA
authors.lastname: Ramírez
authors.forename: O M
authors.initials: OM
authors.lastname: Teme Centurión
authors.forename: E G
authors.initials: EG
authors.lastname: Gros
authors.forename: L R
authors.initials: LR
authors.lastname: Galagovsky
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology*; D002522:Chlorocebus aethiops; D002778:Cholestanones / Q000138:chemical synthesis* / Q000494:pharmacology*; D018259:Herpesvirus 1, Human / Q000187:drug effects / Q000235:genetics; D007210:Indoleacetic Acids / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D008826:Microbial Sensitivity Tests; D013265:Stigmasterol / Q000494:pharmacology; D014709:Vero Cells / Q000821:virology
chemical_list: D000998:Antiviral Agents; D002778:Cholestanones; D007210:Indoleacetic Acids; D013265:Stigmasterol