已开发出丙二酸半硫酯(MAHT)与2-芳基取代的乙烯基砜的不对称脱羧1,4-加成反应,产生的加合物具有出色的对映选择性(最高ee达97%)。考虑到调整p K a值,设计并证明了基于奎宁的苄基取代的硫脲是最有效的催化剂。由脱羧的1,4加成加合物完成了3-甲基茚满酮和(+)-姜黄酮的3-单氟化类似物的对映选择性合成。
Expanding the Utility of Brønsted Base Catalysis: Biomimetic Enantioselective Decarboxylative Reactions
作者:Yuanhang Pan、Choon Wee Kee、Zhiyong Jiang、Ting Ma、Yujun Zhao、Yuanyong Yang、Hansong Xue、Choon-Hong Tan
DOI:10.1002/chem.201100687
日期:2011.7.18
of simple esters, the use of them as nucleophiles in directasymmetric transformations is a long‐standing challenge in synthetic organic chemistry. Nature approaches this difficulty through a decarboxylative mechanism, which is used for polyketide synthesis. Inspired by nature, we report guanidine‐catalyzed biomimetic decarboxylative CC and CN bond‐formation reactions. These highly enantioselective
[EN] DNA ALKYLATION AND CROSS-LINKING AGENTS AS COMPOUNDS AND PAYLOADS FOR TARGETED THERAPIES<br/>[FR] ALKYLATION D'ADN ET AGENTS DE RÉTICULATION COMME COMPOSÉS ET CHARGES UTILES POUR THÉRAPIES CIBLÉES
申请人:UNIV YALE
公开号:WO2017132459A1
公开(公告)日:2017-08-03
The present invention is directed to compounds related to precolibactin, pharmaceutical compositions based upon these compounds and methods of synthesis which are employed to provide intermediates and final compounds, which are principally alkylating agents and anticancer compounds. The chemical synthetic approach disclosed facilitates the synthesis of numerous precolibactin analogs which can be used in the treatment of cancer.
Synthesis of a Tetronic Acid Library Focused on Inhibitors of Tyrosine and Dual-Specificity Protein Phosphatases and Its Evaluation Regarding VHR and Cdc25B Inhibition
作者:Mikiko Sodeoka、Ruriko Sampe、Sachiko Kojima、Yoshiyasu Baba、Takeo Usui、Kazunori Ueda、Hiroyuki Osada
DOI:10.1021/jm0100741
日期:2001.9.1
tetronic acid derivatives were synthesized and evaluated as inhibitors of the dual-specificity protein phosphatases VHR and cdc25B. Several compounds are found to be potentinhibitors of cdc25B, which is a key enzyme for cell-cycle progression. The promising results described herein strongly indicated that this tetronic acidlibrary is potent as a libraryfocused on the PTP/DSP-selective inhibitor.
A Mechanistic Model for Colibactin-Induced Genotoxicity
作者:Alan R. Healy、Herman Nikolayevskiy、Jaymin R. Patel、Jason M. Crawford、Seth B. Herzon
DOI:10.1021/jacs.6b10354
日期:2016.12.7
precolibactins containing a pyridone are not responsible for the genotoxicity of the clb cluster. Instead, we propose that these are off-pathway fermentation products produced by a facile double cyclodehydrationroute that manifests in the absence of viable ClbP. The results presented herein provide a foundation to begin to connect metabolite structure with the disparate phenotypes associated with clb+ E
Precolibactins 和 colibactins 代表了一个由 clb 基因簇编码并由某些共生、肠外和益生菌大肠杆菌产生的天然产物家族。clb+ 大肠杆菌在真核细胞中诱导巨细胞增多症和 DNA 双链断裂,但矛盾的是,这个基因簇是在益生菌 Nissle 1917 中发现的。 证据表明,前大肠杆菌素通过大肠杆菌素肽酶 (ClbP) 介导的 N 裂解转化为基因毒性大肠杆菌素-acyl-d-Asn 侧链,并且所有的分离工作都使用 ΔclbP 菌株来促进 precolibactins 的积累。假设大肠杆菌素形成不饱和亚胺,通过环丙烷开环使 DNA 烷基化 (2 → 3)。然而,由于尚未分离出大肠杆菌素,因此该假设尚未经过实验验证。此外,precolibactins AC (7-9) 含有一种吡啶酮,它不能产生构成该假设基础的不饱和亚胺。为了解决这个问题,我们制备了 13 种合成的大肠杆菌素衍生物,并评估了它们的
Convergent and Modular Synthesis of Candidate Precolibactins. Structural Revision of Precolibactin A
作者:Alan R. Healy、Maria I. Vizcaino、Jason M. Crawford、Seth B. Herzon
DOI:10.1021/jacs.6b02276
日期:2016.4.27
Escherichia coli. The metabolites are encoded by the clb gene cluster as prodrugs termed precolibactins. clb(+) E. coli induce DNA double-strand breaks in mammalian cells in vitro and in vivo and are found in 55-67% of colorectal cancer patients, suggesting that mature colibactins could initiate tumorigenesis. However, elucidation of their structures has been an arduous task as the metabolites are obtained