Thallium trinitrate mediated ring contraction of monocyclic ketones: Stereochemical aspects
摘要:
The reaction of 3- and 4-alkylcyclohexanones with thallium trinitrate (TTN) leads to the alkylcyclopentanecarboxylic acids in good yields and with high degree of stereoselectivity. The ring contraction of 2-methylcyclohexanone gives poor yields and 2,6-dimethylcyclohexanone does not undergo contraction. The observed diastereoselectivities of the reactions agree with the mechanism proposed by McKillop et al. (C) 1997 Elsevier Science Ltd.
Methods of inhibiting the replication of influenza viruses in a biological sample or patient, of reducing the amount of influenza viruses in a biological sample or patient, and of treating influenza in a patient, comprises administering to said biological sample or patient an effective amount of a compound represented by Structural Formula (I):
or a pharmaceutically acceptable salt thereof, wherein the values of Structural Formula (IA) are as described herein. A compound is represented by Structural Formula (IA) or a pharmaceutically acceptable salt thereof, wherein the values of Structural Formula (IA) are as described herein. A pharmaceutical composition comprises an effective amount of such a compound or pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier, adjuvant or vehicle.
(Lig)Ni(0) Induced Preparation of Mono- and Dicarboxylic Acids from Cyclopentene and Carbon Dioxide Cyclopentene is shown to be an ideal substrate for coupling reactions with (Lig)nickel(0) systems. By variation of the ligands and addition of promotors, it is possible by successive application of carbon dioxide or carbon monoxide to prepare highly selectively series of cyclopentane- and cyclopentenecarboxylic acids (six examples), 4, 5, 6, 11, 14, 15, cyclopentanedicarboxylic acids (three examples), 7, 8,12, or 2-hydroxycyclopentanecarboxylic acid (9) in good yields. The C5-skeleton is retained in the products.
The invention provides compounds of Formula (I) and Formula (II), pharmaceutically acceptable salts, pro-drugs, biologically active metabolites, stereoisomers and isomers thereof wherein the variable are defined herein. The compounds of the invention are useful for treating immunological and oncological conditions.
Stereochemistry of the thermal isomerizations of (1R,2R)-1-[(E)-styryl]-2-methylcyclopropane to 3-phenyl-4-methylcyclopentenes
作者:John E. Baldwin、Samuel Bonacorsi
DOI:10.1021/ja00076a021
日期:1993.11
(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane at 250 o C racemizes and isomerizes to 6-phenylhexa-1,4-(Z)-diene and to the four isomers of 3-phenyl-4-methylcyclopentene. From the measured rate constants for racemization and for structural isomerizations, and from information on the relative amounts of the four 3-phenyl-4-methylcyclopentenes as a function of time, the relative contributions of the four
(1R,2R)-1-((E)-Styryl)-2-methylcyclopropane 在 250 o C 外消旋并异构化为 6-苯基六-1,4-(Z)-二烯和 3-苯基-的四种异构体4-甲基环戊烯。从外消旋化和结构异构化的测量速率常数,以及四种 3-苯基-4-甲基环戊烯的相对量随时间变化的信息,四种立体化学不同路径对这种乙烯基环丙烷重排的相对贡献是发现为 60% si、10% ar、19% sr 和 11% ai