Total Synthesis Of Prostaglandin A And Its Derivatives

Protosappanin A is one of effective component of Caesalpinia sappan L which is traditional medicine plant.Many pharmacological activities of Protosappanin A have been reported:immunosuppressive effect,anticancer,Anti-inflammatory,antioxidant and other activities.Due to the fact that the natural sources of Protosappanin A in Caesalpinia sappan L is very little,Protosappanin A was difficult to be extracted,and total synthesis has not been reported to date,so Protosappanin A can't satisfy Pharmacological research's needs.So In this paper,the total synthesis of Protosappanin A was researched,and three total-synthetic routes of Protosappanin A was designed.The total synthesis of Methylation of Protosappanin A have been achieved for the first time by the first and second method respectively,and the first method was researched intensively.In the first method,Methylation Protosappanin A was prepared,using catechol and 3-Methoxyphenol as raw materials,via methylation,bromination,boronization,intermolecular-Suzuki coupling,cyclization,addition,reduction and Tiffeneau-Demjanov rearrangement reaction total 8 steps in 21%overall yield.In the second method,Methylation Protosappanin A also was prepared,using catechol and 3-Methoxyphenol as raw materials,via methylation,bromination,acetylation,?-bromination,condensation,intramolecular-Suzuki coupling,addition,reduction and Tiffeneau-Demjanov rearrangement reaction total 9 steps in 2.2%overall yield.Otherwise in this paper the demethylation of Methylation Protosappanin A was researched preliminary.In the process for synthesis of Protosappanin A,28 new compounds was prepared,including 8 bromobenzene derivatives,11 Diphenyl derivatives,5 seven-member heterocyclic ring compound derivatives,2 phenylboronic acid derivatives,1 eight-member heterocyclic ring compound and 1 benzofuran-3(2H)-one compound.And the structure of these products have been identified by 1HNMR and 13CNMR spectra.