1721-57-9Relevant articles and documents
Synthesis of erythrodiol C-ring derivatives and their activity against Chlamydia trachomatis
Kazakova, Oxana,Rubanik, Liudmila,Lobov, Alexander,Poleshchuk, Nikolai,Baikova, Irina,Kapustina, Yuliya,Petrova, Anastasiya,Korzun, Tatyana,Lopatina, Tatyana,Fedorova, Alexandra,Rybalova, Tatyana,Polovianenko, Dmitri,Mioc, Marius,?oica, Codru?a
, (2021/09/16)
To develop new potential agents against Chlamydia trachomatis among oleanane type triterpenoids the synthesis, spectral and X-ray analysis as well as antimicrobial screening of C-12 oxygen and nitrogen derivatives of erythrodiol is presented. The reduction of methyl 3β-acetoxy-12-oxo-oleanoate with LiAlH4 led to isomeric erythrodiol 12β- and 12α-hydroxy-derivatives, their stereochemistry with respect to the position of hydroxyl-group at C-12 was determined based on the multiplets splitting patterns, the magnitude of the spin–spin interaction, and NOESY interactions. Methyl 3β-acetoxy-12-oxo-oleanoate was transformed to 12E-hydroxyimino- and 12E-methoxyimino-derivatives by the interaction with NH2OH?HCl or CH3ONH2?HCl, respectively. By Beckmann rearrangement with SOCl2 in dioxane 12E-oxime was converted to C-lactame and its following reduction with LiAlH4 in THF or dioxane led to erythrodiol C-azepanone or C-azepane derivatives. The structure 3-O,12-N-bis-acetyl-derivative of C-azepane-erythrodiol was confirmed by the single crystal X-ray analysis. Erythrodiol 12β-hydroxy- and C-azepane derivatives were found to be lead compounds with significant activity against C. trachomatis with MIC 1.56 and 3.125 μg/mL. Molecular docking was employed to suggest potential binding interaction, the tested compounds are likely to act as Cdu1 protein inhibitors while 12β-hydroxy-erythrodiol exhibited the highest affinity towards this respective target protein. These results indicated that C-ring oxygen and nitrogen erythrodiol derivatives might be considered for further research in the design of antibacterial agents against Chlamydia trachomatis.
Total syntheses of (+)-arisugacins F, G
Chen, Ping,Li, Yu,Tang, Yu,Wu, Hao
, (2020/07/20)
(+)-Arisugacin F and G are synthesized from commercially available oleanolic acid in 9 and 10 steps, respectively. This strategy features a AgOTf/Pd(PPh3)4-mediated cis/trans olefin isomerization and a highly convergent formal oxa-[3 + 3] cycloaddition between key α, β-unsaturated aldehyde and pyrone, which lays the foundation for efficient and concise synthesis of other natural products with similar terpenoid scaffolds.
Ursolic and oleanolic acid derivatives with cholinesterase inhibiting potential
Loesche, Anne,K?witsch, Alexander,Lucas, Susana D.,Al-Halabi, Zayan,Sippl, Wolfgang,Al-Harrasi, Ahmed,Csuk, René
, p. 23 - 32 (2019/01/04)
Triterpenoids are in the focus of scientific interest, and they were evaluated for many pharmacological applications among them their ability to act as inhibitors of cholinesterases. These inhibitors are still of interest as drugs that improve the life quality of patients suffering from age-related dementia illnesses especially of Alzheimer's disease. Herein, we prepared several derivatives of ursolic and oleanolic acid and screened them in Ellman's assays for their ability to inhibit acetylcholinesterase and/or butyrylcholinesterase, and for each of the active compounds the type of inhibition was determined. As a result, several compounds were shown as good inhibitors for acetylcholinesterase and butyrylcholinesterase even in a micromolar range. An ursolic acid derived hydroxyl-propinyl derivative 10 was a competitive inhibitor for butyrylcholinesterase with an inhibition constant of Ki = 4.29 μM, and therefore being twice as active as gold standard galantamine hydrobromide. The best inhibitor for acetylcholinesterase, however, was 2-methyl-3-oxo-methyl-ursoloate (18), acting as a mixed-type inhibitor showing Ki = 1.72 μM and Ki′ = 1.28 μM, respectively.
