Asymmetric synthesis and absolute configuration of (-)-trypargine.
作者:MASATO SHIMIZU、MASAYUKI ISHIKAWA、YASUO KOMODA、TERUMI NAKAJIMA、KEIICHI YAMAGUCHI、SHINICHIRO SAKAI
DOI:10.1248/cpb.32.1313
日期:——
An asymmetric synthesis of (1S)-(-)-trypargine (1a) was accomplished. The Pictet-Spengler condensation of (+)-Nb-benzyl-D-tryptophan methyl ester ((+)-3) with α-ketoglutaric acid, followed by methylation of the resulting monocarboxylic acid ((-)-4a), provided (1S, 3R)-(-)-methyl 2-benzyl-3-methoxycarbonyl-1, 2, 3, 4-tetrahydro-9H-pyrido [3, 4-b] indole-1-propionate ((-)-6a), which was converted into (-)-trypargine (1a). The absolute configuration of natural trypargine (1a) at the C-1 position was determined to be S.
成功实现了(1S)-(-)-trypargine (1a)的不对称合成。首先将(+)-Nb-苄基-D-色氨酸甲酯((+)-3)与α-酮戊二酸进行Pictet-Spengler缩合,随后对所得的单羧酸((-)-4a)进行甲基化,得到了(1S, 3R)-(-)-甲基2-苄基-3-甲氧基羧基-1, 2, 3, 4-四氢-9H-吡啶[3, 4-b]吲哚-1-丙酸((-)-6a),进一步转化为(-)-trypargine (1a)。天然trypargine (1a)在C-1位的绝对构型被确定为S。