Stereochemical Outcomes in Reductive Cyclizations To Form Spirocyclic Heterocycles
作者:Matthew A. Perry、Richard R. Hill、Justin J. Leong、Scott D. Rychnovsky
DOI:10.1021/acs.orglett.5b01422
日期:2015.7.2
Reductive lithiation and cyclization of N-Boc α-amino nitriles are often highly stereoselective. The alkyllithium intermediates are formed with varying levels of selectivity, but the alkyllithium geometry does not play a major role in the overall stereoselectivity. The final configuration is determined in the cyclization reaction, where both retention and inversion pathways are observed. Where strong
N -Bocα-氨基腈的还原锂化和环化通常具有很高的立体选择性。形成的烷基锂中间体具有不同的选择性水平,但烷基锂的几何形状在总体立体选择性中不发挥主要作用。最终构型是在环化反应中确定的,在该反应中观察到了保留和转化途径。在产物中存在强烈的热力学偏好的地方,动力学控制的烷基锂环化有利于更稳定的产物。
Proline-like β-turn mimics accessed via Ugi reaction involving monoprotected hydrazines
A four-center, three-component Ugi-type reaction of a variety of keto acids, Boc- or Cbz-protected hydrazine, and isocyanides offers a simple and high yielding access to cyclic products containing an N-aminolactam unit. The latter are shown to form consistently an intramolecular hydrogen bond leading to a p-turn-like secondary structure. The possibility of integrating such N-aminolactam units (without disruption of the folded structure) into pseudotripeptide fragments is demonstrated. (C) 2010 Elsevier Ltd. All rights reserved.
Sequenced Reactions with Samarium(II) Iodide. Sequential Intermolecular Carbonyl Addition/Intramolecular Nucleophilic Acyl Substitution for the Preparation of Seven-, Eight-, and Nine-Membered Carbocycles
作者:Gary A. Molander、Cristina Alonso-Alija
DOI:10.1021/jo980119e
日期:1998.6.1
Samarium(II) iodide has been employed to promote a tandem intermolecular carbonyl addition/intramolecular nucleophilic acyl substitution sequence, generating seven- through nine-membered monocyclic, bicyclic, and tricyclic ring systems with good yields and high diastereoselectivities. This tandem reaction consists of an intermolecular reaction followed by an intramolecular ring expansion that results in a formal [m + n] cycloaddition, starting from extremely simple, readily available substrates. The regioselectivity and stereoselectivity of the process arise from a tuning of the reducing power of samarium(II) iodide with nickel(II) iodide in the first step and irradiation with visible light in the second. By using this method, a variety of structural motifs have been assembled rapidly in good yields.
US20140256660A1
申请人:——
公开号:US20140256660A1
公开(公告)日:2014-09-11
[EN] CERTAIN CHEMICAL COMPOSITIONS AND METHODS OF USE THEREOF<br/>[FR] COMPOSITIONS CHIMIQUES PARTICULIÈRES ET LEURS PROCÉDÉS D'UTILISATION
申请人:ALGEN BIOTECHNOLOGIES INC
公开号:WO2021231892A1
公开(公告)日:2021-11-18
The present disclosure provides CDK9 inhibitors. Also provided are methods of treating a disease or a disorder comprising administering to a subject in need of treatment one of the CDK9 inhibitors disclosed herein. In some embodiments, the disease or disorder to be treated is cancer. In some embodiments, the disease or disorder is liver cancer.