Studies On The Synthesis Of Natural Products Containing1,3-diol Subunits Using Inexpensive And Readily Available Chiral Building Blocks

This MS degree thesis centers on the construction of the1,3-diol subunits in natural products using enantiopure epoxy chiral building blocks (S)-1-((R)-2,2-dimethyl-1,3-dioxolan-4-yl)-2-((S)-oxiran-2-yl ethanol (2-2) and (S)-1-((R)-2,2-dimethyl-1,3-dioxolan-4-y1)-2-((R)-oxiran-2-yl) ethanol (2-1) derived from inexp-ensive and readily available D-glucolactone. Efforts were first made in improving the access to the enantiopure epoxy chiral building blocks required for the later endeavors directed towards synthesis of natural products. Then, attention was paid to the elaboration of the enatiopure epoxy chiral building block into (-)-Harzialactone A. We can synthesize this compound by using our enantiopure epoxy chiral(2-l). The work along this line led to an efficient route to this interesting small compound.There are many advantages of this method, such as concise route, convenient operation, high yied and high stereoselectivity. Finally, a more challenging target containing a hidden1.3-diol motif, Koshikalide, was dealt with. The target compound, which to our knowledge has not been synthesized to date, was retrosynthetically disconnected into a diol fragment and a triene fragment. The diol fragment can be synthesizd from the enantiopure epoxy chiral2-1. Both fragments were successfully constructed with all the configurations of the stereogenic centers and the C-C double bonds reliably secured. Coupling of the fragments and subsequent elaborations leading to the end product are under way.