Efficient Alternative Synthetic Route to Diltiazem via (2R,3S)-3-(4-Methoxyphenyl)glycidamide.
作者:Shin-ichi YAMADA、Ikuko TSUJIOKA、Takeji SHIBATANI、Ryuzo YOSHIOKA
DOI:10.1248/cpb.47.146
日期:——
An effective new route to diltiazem, a representative coronary vasodilator, through (-)-(2R, 3S)-3-(4-methoxyphenyl)glycidamide [(-)-2] has been achieved. The glycidamide (-)-2 was prepared in 43% overall yield by a combination of the enzymatic resolution of methyl (±)-(2RS, 3SR)-3-(4-methoxyphenyl)glycidate [(±)-1] with lipase and the following amidation of (-)-1 with ammonia. A one-pot synthesis through the treatment of (-)-2 with 2-aminothiophenol and a following ring closing reaction efficiently gave a key intermediate of diltiazem synthesis, (2S, 3S)-2, 3-dihydro-3-hydroxy-2-(4-methoxyphenyl)-1, 5-benzothiazepin-4(5H)-one [cis-(+)-5] in 80% overall yield.
已经通过(-)-(2R,3S)-3-(4-甲氧基苯基)缩水甘油酰胺[(-)-2]实现了一种有效的新途径地尔硫卓(一种代表性的冠状血管扩张剂)。通过结合 (±)-(2RS, 3SR)-3-(4-甲氧基苯基)缩水甘油酸酯 [(±)-1] 与脂肪酶的酶解,制备出缩水甘油酰胺 (-)-2,总产率为 43%以及以下(-)-1与氨的酰胺化。通过用 2-氨基苯硫酚处理 (-)-2 和随后的闭环反应,一锅合成有效地得到了地尔硫卓合成的关键中间体 (2S, 3S)-2, 3-二氢-3-羟基-2 -(4-甲氧基苯基)-1, 5-苯并硫氮杂卓-4(5H)-酮[顺式-(+)-5],总收率80%。