3种trans-3-甲基-γ-烷内酯类手性香料的制备  

Preparation of 3 Kinds of trans-3-Methyl-γ-Lactones Chiral Flavors

作　　者：姜若含 尹舒婷 牟雪瑶 梁森[1] 孙宝国[1] 田红玉[1] JIANG Ruohan;YIN Shuting;MU Xueyao;LIANG Sen;SUN Baoguo;TIAN Hongyu(School of Food and Health,Beijing Technology and Business University,Beijing 100048,China)

机构地区：[1]北京工商大学食品与健康学院,北京100048

出　　处：《食品科学技术学报》2024年第6期35-44,共10页Journal of Food Science and Technology

基　　金：国家自然科学基金重点项目(32130083)。

摘　　要：手性化合物在风味研究领域中占据着重要地位,其中拥有两个手性中心的3-甲基-γ-烷内酯类化合物是一类非常关键的食用香料,主要用于配制桃、椰子、香草等类型的香精。因3-甲基-γ-烷内酯类化合物较高的水溶性,也作为香料广泛应用于酒水、饮料中。以往的3-甲基-γ-烷内酯类化合物合成方法存在着起始原料不易获得、操作复杂、通用性差等缺陷。探讨了光学活性的trans-3-甲基-γ-辛内酯、壬内酯和癸内酯的制备方法。以相应的脂肪醛、丙二酸为起始原料通过Knoevenagel缩合制得(E)-3-烷烯酸,利用其甲酯进行Sharpless不对称双羟基化反应构建手性中心,然后通过消除反应和共轭加成反应得到目标产物。所有产物的结构都通过NMR和G C-MS进行了确认,目标产物的对映体过量(enantiomeric excess,ee)值通过手性GC进行了测定,(3R,4S)-trans-3-甲基-γ-辛内酯和(3S,4R)-trans-3-甲基-γ-辛内酯ee值分别为84%和92%;(3R,4S)-trans-3-甲基-γ-壬内酯和(3S,4R)-trans-3-甲基-γ-壬内酯ee值分别为87%和95%;(3R,4S)-trans-3-甲基-γ-癸内酯和(3S,4R)-trans-3-甲基-γ-癸内酯ee值分别为83%和96%。制备的对映体均分别呈现出不同程度的椰子香、甜香、焦香等明显不同的香气特征;3种内酯反式构型的产物,其对映体的香气特征均表现出显著的差异。Chiral compounds play an important role in flavor research,among which 3-methyl-γ-lactones with two chiral centers are a key class of spices,mainly used to prepare peach,coconut,vanilla and other flavors.Because of its water solubility,it is also widely used in alcohols and beverages as a food additive.The previous synthetic methods often had defects such as difficult acquisition of starting materials,complicated operation,and poor versatility.The process involved obtaining optically active trans-3-methyl-octanolide,nonanolide,and decanolactone was explored.(E)-3-alkenoic acids starting from the corresponding aliphatic aldehydes and malonic acid were synthesized through Knoevenagel condensation.Subsequently,their methyl esters underwent Sharpless asymmetric dihydroxylation to introduce chiral centers,followed by elimination and conjugate addition steps to yield the desired target compounds.The final structures of all products were confirmed by NMR and G C-MS,and the enantiomeric excess(ee)values of the final products were determined by chiral GC.The enantiomeric excess(ee)values for(3R,4S)-trans-3-methyl-γ-octanolides and(3S,4R)-trans-3-methyl-γ-octanolides were 84%and 92%,respectively.For(3R,4S)-trans-3-methyl-γ-nonanolides and(3S,4R)-trans-3-methyl-γ-nonanolides,the ee values were 87%and 95%,and for(3R,4S)-trans-3-methyl-γ-decanolides and(3S,4R)-trans-3-methyl-γ-decanolides,the values were 83%and 96%.Notably,each enantiomer exhibited distinct odor characteristics.All presented different degrees of coconut aroma,sweet aroma,and burnt aroma.The aroma characteristics of the enantiomers of the three lactone trans-configuration products prepared in this paper all showed significant differences.

关 键 词：trans-3-甲基-γ-内酯 (E)-3-烷烯酸甲酯 Sharpless不对称双羟基化 手性香料 KNOEVENAGEL缩合 

分 类 号：TS202.3[轻工技术与工程—食品科学] O621.3[轻工技术与工程—食品科学与工程]