干姜中的二芳基庚烷类化合物及其在四逆汤煎煮过程中的立体选择性反应

Diarylheptanoids in Rhizoma Zingiberis and Their Stereoslective Reactions During the Process of Decocting

采用高效液相色谱多级质谱联用鉴定了干姜水煎剂的18个二芳基庚烷类化合物。发现此类化合物的电喷雾质谱碰撞诱导裂解反应的特征主要表现在吡喃环的次级逆Diels Alder反应裂解或C1和C5OH发生次级麦氏重排裂解,这两种裂解反应对归属芳环的取代非常重要。比较了复方四逆汤配伍对二芳基庚烷类化合物的影响,从色谱保留行为、质谱数据等推测化合物2-(3,4-二羟基-5-甲氧基苯基)-6-(3,4-二羟基苯乙基)-2氢-吡喃-4-醇(Ⅲ-1)的一组差向异构体,2-(3,4-二羟基-5-甲氧基苯基)-6-(4-羟基苯乙基)-2氢-吡喃-4-醇(Ⅲ-2)的一组差向异构体以及2-(3,4-二羟基-5-甲氧基苯基)-6-(4-二羟基-3-甲氧基苯乙基)-2氢-吡喃-4-醇(Ⅲ-3)的2组差向异构体在复方煎煮过程中发生显著的立体选择性反应,由外消旋体变成单一旋光异构体。吡喃环4-位的乙酰化可能是减少这种反应的关键因素。

18 diarylheptanoids had been identified from the decoction of Zingiber officinale. 4 isomers of 2- （ 3,4,5 -trihydroxylphenethyl ） -6- （ 3,4 -dihydroxylphenylethyl ） -2 H -pyran-4-ol were assumed to be new compounds. Reverse Diels Alder reaction （RDA） fragmentation and Me Lafferty rearrangement reaction were the characteristic collision induced disassociation reaction of diarylheptanoids in ginger. The relative concentrations of these 18 compounds in zinger and compound Sini-Tang decoction were also compared. Four racemic bodies, 2-（ 3,4-dihydroxyl-5-methoxylphenethyl ） -6-（ 3,4-dihydroxylphenylethyl ） -2H-pyran-4-ol, 2-（ 3,4- dihydroxyl-5 -methoxyl phenlethyl ） -6- （ 4-hydroxylphenylethyl ） -2H-pyran-4-ol, and two of 2- （ 3,4-dihydroxyl- 5-methoxylphenlethyl）-6-（ 4-hydroxyl-3-methoxylphenylethyl ）-2H-pyran-4-ol in Rhizoma zingiberis was approximately 1 ： 1 in concentration. But one epimer of each racemic bodies above-mentioned were not detected in Sini-Tang decoction. In contract, four racemic bodies, 1 -（ 3,4-dihydroxylphenyl ） -7-（ 4-hydroxyl-3, 5- dimethoxylphenyl ）-5-hydroxyl-3-acetylheptan, 2-（ 4-hydroxy-3-methoxyphenethyl ）-tetrahydro-6-（ 3, 4- dihydroxy-5 -methoxyphenylethyl ） -2H-pyran-4-ol acetate ） and two of 2-（ 3,4,5-trihydroxylphenethyl ） -6- （ 3,4- dihydroxylphenylethyl）-2H-pyran-4-ol, which were obviously different in concentrations in decoction of Rhizoma zingiberis, obtained the same recovery rate in Sini-Tang decoction. These results suggested that the mixture of herbs under the direction of theory of Traditional Chinese Medicinal might change the relative concentrations of compositions in herb, which might change the usages of herbs.