通过将一种酶在有机介质中的两种催化活性结合在一起,即一种来自锌的D-氨基酰化酶(DA)的迈克尔加成/酰化活性,开发了一种简便的一锅合成含单糖嘧啶衍生物的路线。大肠杆菌。首先,研究了逐步方法。在此反应体系中,DA对迈克尔加成反应的活性高于酰化反应。嘧啶向丙烯酸乙烯基酯的酶促迈克尔加成反应进展非常迅速,嘧啶向丙烯酸乙烯基酯的迈克尔加成反应的初始反应速率为7.2–16.5 mM min -1。通过结合不同的对照实验证明了氨基酰基纤维素对迈克尔加成的催化特异性。然后,可以在一个锅中执行两个步骤,并构建了一个单一的氨酰酶催化的一锅生物转化。使用这种策略,有效地制备了一系列具有潜在生物学和药理应用的糖-嘧啶复合物。锌依赖性氨基酰基纤维素的这种高迈克尔加成活性以及结合了两种体外催化活性的新颖的单一氨基酰基酶催化的一锅合成,在扩大酶的应用范围和开发新的生物催化剂方面具有实际意义。
Photochemical intermolecular dearomative cycloaddition of bicyclic azaarenes with alkenes
作者:Jiajia Ma、Shuming Chen、Peter Bellotti、Renyu Guo、Felix Schäfer、Arne Heusler、Xiaolong Zhang、Constantin Daniliuc、M. Kevin Brown、Kendall N. Houk、Frank Glorius
DOI:10.1126/science.abg0720
日期:2021.3.26
highly regio- and diastereoselective intermolecular [4 + 2] dearomative cycloaddition reaction of these bicyclic azaarenes with a plethora of electronically diverse alkenes. This approach bypasses the general reactivity and selectivity issues, thereby providing various bridged polycycles that previously have been inaccessible or required elaborate synthetic efforts. Computational studies with density
Regioselective Enzymatic Acylation of Aureolic Acids to Obtain Novel Analogues with Improved Antitumor Activity
作者:Javier González-Sabín、Luz Elena Núñez、Alfredo F. Braña、Carmen Méndez、José A. Salas、Vicente Gotor、Francisco Morís
DOI:10.1002/adsc.201100944
日期:2012.5.21
A variety of aureolicacids was efficiently obtained by lipase‐catalyzed regioselectiveacylation reactions of mithramycin and its analogues mithramycin SK and mithramycin SDK. The acylation took place in the aglycone moiety or in the B sugar unit, depending on the substrate, lipase and acyl donor considered. Most of the novel acylated derivatives showed antitumoractivity at double digit nanomolar
A novel and highly regioselective biocatalytic approach to acetylation of helicid by using whole-cell biocatalysts in organic solvents
作者:Rong-Ling Yang、Xiang-Jie Zhao、Ting-Ting Wu、Muhammad Bilal、Zhao-Yu Wang、Hong-Zhen Luo、Wen-Jun Yang
DOI:10.1016/j.catcom.2019.105707
日期:2019.8
was applied in the highly efficient and regioselective acylation of helicid with fatty acid vinyl esters for the first time. Pseudomonas aeruginosa GDM 1.443 displayed the highest conversion and initial rate among the microbial strains tested. Under the optimal operating conditions, the initial reaction rate was 3.4 mM/h, whereas the substrate bioconversion and regioselectivity were 99%. Moreover,
首次将完整的微生物细胞生物催化方法应用于螺旋体与脂肪酸乙烯基酯的高效和区域选择性酰化反应。铜绿假单胞菌GDM 1.443在测试的微生物菌株中显示出最高的转化率和初始速率。在最佳操作条件下,初始反应速率为3.4 mM / h,而底物的生物转化率和区域选择性为99%。此外,合成了一系列具有优良转化率和区域选择性的6'-酯类螺旋。由于与酶催化位点的相互作用不同,反应速度随酰基供体的变化而变化很大。总而言之,新开发的路线可能为螺旋脂肪酸酯的形成提供了很高的潜力。
Na2CO3-Catalyzed O-Acylation of Phenols for the Synthesis of Aryl Carboxylates with Use of Alkenyl Carboxylates
作者:Xiao-Yu Zhou、Xia Chen
DOI:10.1055/s-0037-1610265
日期:2018.10
phenol and its derivatives has been developed. The procedure provides an efficient catalysis system for the preparation of aryl carboxylates with alkenyl carboxylates as acyl reagents. The reaction proceeded smoothly by using Na2CO3 as the catalyst in MeCN to produce the corresponding aryl carboxylates in good to excellent yields.
Chemoenzymatic synthesis of optically active γ-alkyl-γ-butenolides
作者:Mikio Fujii、Motonori Fukumura、Yumiko Hori、Yasuaki Hirai、Hiroyuki Akita、Kaoru Nakamura、Kazuo Toriizuka、Yoshiteru Ida
DOI:10.1016/j.tetasy.2006.08.001
日期:2006.9
rac-Hept-1-en-3-ol 4 was subjected to an enantioselective esterification in the presence of Novozyme 435 and vinyl crotonate as the acyl donor to give (3S)-oct-1-en-3-yl crotonate 7 in >99% ee and (3R)-alcohol 4 in 99% ee. The E-value of this enzymatic reaction was found to be >1000. The (S)-crotonic ester 7 was converted by ring-closing metathesis (RCM) using Grubbs’ catalyst to give (S)-oct-2-en-4-olide