Rationalizing the Formation of Damascenone: Synthesis and Hydrolysis of Damascenone Precursors and Their Analogues, in both Aglycone and Glycoconjugate Forms
作者:Merran A. Daniel、Carolyn J. Puglisi、Dimitra L. Capone、Gordon M. Elsey、Mark A. Sefton
DOI:10.1021/jf8018134
日期:2008.10.8
megastigma-4,6,7-trien-9-ol (7) and megastigma-6,7-dien-9-ol (8) were synthesized. No 1,3-transposition of oxygen to form analogues of damascenone was observed when 7 and 8 were subjected to mild acidic conditions. Such transposition takes place only with highly conjugated acetylenic precursors such as 6 or tertiary allenic alcohols such as 2. The placement of glucose at C-3 of 5 and at C-9 of 6 gave the
megastigma-4,6,7-trien-3,9-diol(5)和megastigma-3,4-dien-7-yn-9-ol(6)在pH 3.0和3.2的乙醇水溶液中储存仅在室温下为damascenone(1)和damascenone加合物。二醇(5)在pH 3.0和pH 3.2下分别具有32和48小时转化的半衰期。在相同的pH值下,炔醇(6)的半衰期分别为40和65 h。为了研究5和先前研究的烯丙三醇2中C-9羟基官能团的反应性,两种模型化合物megastigma-4,6,7-trien-9-ol(7)和megastigma-6,7合成了-dien-9-ol(8)。当将7和8置于温和的酸性条件下时,未观察到氧的1,3-易位形成大马mas酮的类似物。仅用高度共轭的炔属前体(如6)或叔烯丙醇(如2)进行这种转座。将葡萄糖分别置于C-3为5和C-9为6时分别得到糖苷9和10。这种葡糖缀合的