| 摘要 |
<p>PURPOSE:To obtain the subject compound existing as a communicating substance of insects in the natural world in high optical purity in a short step by using an inexpensive and readily available D-ribose as a starting substance and carrying out reaction such as oxidation and reduction. CONSTITUTION:D-Ribose expressed by formula I is made to react with an acetalizing agent to protect hydroxyl groups at the 2- and the 3-positions and the resultant protected D-ribose is subsequently allowed to react with an organometallic reagent to afford a compound expressed by formula II (R is 2-10C alkyl; R<1> and R<2> are protecting group of OH). The 1,2-diol part of the compound expressed by formula II is then oxidatively cleaved, simultaneously cyclized and further oxidized. The protecting groups at the 2- and 3-positions and hydroxyl groups are released to afford a compound expressed by formula III. The double bond between the 2- and the 3-positions in the compound expressed by formula III is reduced in a hydrogen atmosphere in the presence of a hydrogenating catalyst (e.g. Raney nickel) to provide the objective (S)-gamma- lactone expressed by formula IV.</p> |
