通过手性腈的无氰化物合成和醛肟脱水酶催化的坎普消除反应的结合,我们在此报道醛肟脱水酶在5-sub-4,5-二氢异恶唑的不对称开环中合成手性β的新应用-羟基腈,具有广泛的底物范围,出色的对映选择性(高达99%ee)和良好的周转率(高达11 s -1)。简单分离并用碱性试剂处理后,剩余的手性5-sub-4,5-二氢异恶唑可轻松转化为它们相应的β-羟基腈。使用定点诱变,证实了含亚铁血红素的活性位点,并提出了两种可能的去质子化途径。据我们所知,这是第一个用于从一个简单的烯烃一步一步构建手性羟基和腈基的酶促反应,这为合成β-羟基互补对映异构体提供了一种新颖而有用的策略腈。
A process for producing a calcium carboxylate comprising contacting a nitrile compound, a calcium compound selected from calcium hydroxide, calcium oxide or mixtures thereof, and water at a temperature of about 90°C to about 250°C at a sufficient pressure and for a sufficient time to produce a reaction mixture comprising calcium carboxylate.
A process for producing a calcium carboxylate comprising contacting a nitrile compound, a calcium compound selected from calcium hydroxide, calcium oxide or mixtures thereof, and water at a temperature of about 90° C. to about 250° C. at a sufficient pressure and for a sufficient time to produce a reaction mixture comprising calcium carboxylate.
Compounds of Formula (I), and pharmaceutically acceptable salts, esters, and prodrugs thereof: (I) are disclosed, wherein A, B, D, L, X, Y, Z and R
2′
, are described herein. The compounds exhibit antibacterial properties. The compounds of Formula (I) can be employed to treat or prevent bacterial infections as compounds per se or in the form of pharmaceutically acceptable salts, esters, or prodrugs. The compounds and their salts, esters, and prodrugs can also be employed as ingredients in pharmaceutical compositions, optionally in combination with other antibacterial agents, for the treatment of bacterial infections. Processes for making the compounds are also disclosed.
Organozinc compounds derived from α-bromonitriles are readily prepared in solution in tetrahydrofuran (THF) and exist in the C metallated form. They condense normally with aldehydes and saturated ketones. A number of new β-hydroxy-nitriles are described. The addition of conjugated unsaturated ketones results in the formation of β-hydroxynitriles or ketonitriles, depending on the nature of the initial
Greener and regioselective ring opening of epoxides with TMSCN using potassium salts of magnetic carbon nitride
作者:Mostafa Saadat、Mahnaz Qomi、Najmedin Azizi
DOI:10.1007/s00706-020-02689-0
日期:2020.10
green and recyclable catalyst for rapid and regioselective ring opening of epoxides with TMSCN, yielding the β-hydroxynitrile ring-opened products undermild reaction conditions. It is manageable to large-scale preparation with simple instruments and gives the desired compounds in short reaction times with good-to-excellent yields (73–95%) undersolvent-freeconditions. Magnetic separation protocol has
摘要 磁性石墨碳氮化碳(Fe 3 O 4 @gC 3 N 4 -K)的钾盐经合成,被证明是一种绿色且可回收的催化剂,可用于通过TMSCN快速和区域选择性地使环氧化物开环,生成β-羟基腈开环产物在温和的反应条件下。使用简单的仪器即可进行大规模制备,并且在无溶剂条件下以较短的反应时间即可获得所需化合物,并具有良好至优异的收率(73–95%)。磁分离方案已使用外部磁体实现了从未纯化的反应混合物中简单分离和重复使用催化剂,而在五个循环后没有损失催化操作。 图形摘要