Study On Bioactive Molecules-Oriented Catalytic Methodologies And The Synthesis Of β-Carbline-Type Natural Products

In modern organic synthesis, whether the synthesis of drug molecule, or construction of natural products, it is aim to develope the approaches of high selectivity, high rate, low pollution and atom economy. This makes it particularly important to develope good catalytic systems. Meanwhile, the systems often could shorten the reaction steps, which are opening up new practical routes for the synthesis of natural products and drug molecules. This thesis studied several types of catalytic methodology and the synthesis of several natural products with biological activity. This thesis includes the following three parts:Firstly, based on the review of the metal-catalyzed reactions of C(aryl)-S bond formation, it was studied the cross coupling reaction of aromatic heterocyclic thione and ArI derivatives. The reaction was performed using an inexpensive catalyst (CuI), readily available ligand (1,10-phenanthroline) under very mild basic conditions(K2C03). We obtained 36 aromatic heterocyclic sulfur ethers in good to excellent yields and chemoselectivity. The chemoselectivity of the reaction was confirmed by mass spectrometry and single crystal diffraction. It was deduced that the heterocyclic compounds could possess potential biological activity.Second, we first reported a highly enantioselective aza-Friedel-Crafts reaction of 2-naphthol with tosylimines catalyzed by a dinuclear zinc complex for the synthesis of optically active Betti base derivatives. A wide variety of aryl aldimine substrates and aliphatic aldimine could be employed successfully. In order to obtain Betti base, sodium/naphthalene in dry THF was used to deprotect Ts group and the (R)-Betti base could be obtained successfully.Finally, we explore the synthesis of tangutorine by enantioselective Aza-Friedel-Crafts reaction and asymmetry reduction reactions and the skeleton synthesis of several Maroline type of indol alkaloid by asymmetry Michael reaction. These synthetic routes are based organic catalysis in order to reflect the efficiency, specificity, environmentally friendly.