Study On The Sythesis And Characterization Of Guaiane Derivatives

Curcumol is one of the active ingredients of curcuma oil, a promising anticancer drug. Its functions are anti-tumor, anti-virus, anti-inflammatory and so on. Up to now, the reports of structure modification of curcumol by organic methods are rare.In this paper, the structure modification of curcumol at C-7 and 0-11 was studied. Exocyclic double bond oxidation was the first step of structure modification of curcumol at C-7. After hydrolysis of hemiketal and Michael addition reaction, enantiomers were generated. The products were complicated because the stable structure of curcumol had been broken by the hydrolysis of hemiketal.Via two-step reaction:exocyclic double bond oxidation, then oxygen bridges acylation within the seven-membered ring. Reaction product was purified by silica gel column chromatography. Compound 4 was characterized by IR, ESI-MS,*H NMR,13C NMR and 2D NMR (gCOSY, gHSQC, gHMBC) techniques. The 1H NMR and 13C NMR signals of compound 4 were assigned. Its structure was elucidated as 8-hydroxyl-12-isopropyl-2-methyl-tricyclo [6.2.2.01,5] dodecane-10-oxa-6,9-dione, a novel curcumol derivative.In our study, the structural modification of curcumol at C-7 was carried out by rearrangement, oxidation, ring-opening reaction. And we got 6,7-epoxide,7-carbonyl and 7-hydroxy derivatives, etc. Because of the intramolecular hydrogen bond between 7-carbonyl and 8-hydroxy, Michael addition reaction and amination reduction reaction were not finished. To solute this problem, the 8-hydroxy was protected first. Open the epoxide by lewis acid. Based on the data of NMR experiment, a thorough discussion of the epoxidation and ring opening reaction mechanism was proposed.