Study On Total Synthesis Of Natural Chalcone And Labdane Diterpenes

This thesis focuses on the study of the total synthesis of four chiral chalcones, three Benzopyran chalcones and one Labdane diterpenoid natural product Pacovatinin B. The thesis includes five parts as follows:1. The first chapter reviews the moleular structure, classification, biological activity and synthetic methods of chalcones briefly.2. First Enantioselective Synthesis of (±)Brosimacutins H and IThe enantioselective synthesis of natural (±)Brosimacutins H and I was achieved through protection of phenolic hydroxyl group, C-prenylation, sharpless asymmetric dihydroxylation, aldol condensation, Pd-C/H2 reduction and deportection starting from cheap 4-hydroxybenzaldehyde, 4-hydroxyphenoacetophenone,2,4-dihydroxybenzaldehyde,2,4-dihydroxyacetophenone.3. Total synthesis of three Benzopyran chalconesThe total synthesis of three Benzopyran chalcones was achieved through oxidation, reduction, friedel-crafts, benzopyran, protection of phenolic hydroxyl group, aldol condensation, deprotection starting from isovanillin,2,3-Dihydroxybenzaldehyde,2,5-Dihydroxybenzaldehyde.4. study on the biological activity of chalcones compoundsTested the antioxidant activity of compounds 1-3 by using DPPH·radical scavenging capacity to measure the antioxidant activity, then, compared with Vc, studied scavenging effect of three compounds on DPPH·, in order to provide reference datas for the antioxidative effect of chalcones.In addition, studied the antibacterial activity of compounds 1-3 with gram positive bacteria and gram negative bacteria by using the broth microdilution method.The result showeds that compounds 1-3 had good inhibition activity on these tow kinds of bacteria, the inhibitory effect of compounds 2 and 3 were obvious, they had a certain pharmacological application prospect.5. Total synthesis of Pacovatinin BThe synthesis of "Labdane" diterpenoid natural product Pacovatinin B was introduced.The total enantioselective synthesis of compound 10 was achieved in 8 steps from geraniol. The synthesis of the important precursor of "Labdane" diterpenoid Pacovatinin B was completed by using compound 10 as the raw material.All structure of new compounds were confirmed by 1H NMR,13C NMR and HRMS.