Total Synthesis of Alvaradoins E and F, Uveoside, and 10-epi-Uveoside

Abstract

CHAPTER 2: METHODOLOGY IN ANTHRONE C-GLYCOSIDE SYNTHESIS 2.1 Introduction………………………………………………………..……………..……8 2.2 Alkylation of anthrones………..……………………………………………………....8 2.3 In-vitro biosynthesis of the C-glycosidic bond in aloin …………………...….………8 2.4 Total synthesis of cassialoin……………………………….…………………..……...9 CHAPTER 3: SYNTHESIS OF ALVARADOINS E & F, UVEOSIDE, AND 10-EPI-UVEOSIDE 3.1 Introduction…………………………………………..………....………………...…11 3.2 Objectives and retrosynthetic analysis ………...…………………………….………12 3.3 Synthesis of fragment 8……………………………………………………...………13 3.4 Synthesis of fragment 9a…………………………………………………….………13 3.5 Model studies for the formation of anthrone-C-glycoside……...…..……….………14 3.6 Formation of carboxylic acid intermediate ………………………………………….17 3.7 Conversion to anomeric acetate………………………………………….…………..18 3.8 Hydrolysis of isobutyrate and acetate esters…………………………………………20 vi 3.9 Completion of the synthesis of alvaradoins E and F…..……………………………..21 3.10 Completion of the synthesis of uveoside and 10-epi-uveoside……………...……...22 CHAPTER 4: CONCLUSION …………………………………….