Design and synthesis of macro-heterocycles structurally related to tirofiban
摘要:
Sequences of nine and four steps were designed to yield two tirobifan related macrocycles by SN2 macrocyclization. The cyclic compounds contain the amino acid tyrosine, one insaturation and are either 18- or 20-membered rings. All the reaction conditions are very mild and the overall yields indicate that the results depend a lot on the structure of the targets and on the length of the reaction sequence. (C) 2000 Published by Elsevier Science Ltd.
本文报道的是铜催化的S N 2'选择性烯丙基取代反应,该反应使用易于获得的烯丙基氯化物和1,1-二硼烷基烷烃,该反应随着1,1-二硼烷基烷烃的化学选择性C-B键活化而进行。在催化量的[Cu(IMes)Cl] [IMes = 1,3-双(2,4,6-三甲基苯基)咪唑-2-亚烷基]和LiO t Bu为碱的情况下,一系列伯仲烯丙基氯化物经过S N 2'-选择性烯丙基取代反应,生成支链烷基硼酸酯。还介绍了所得烷基硼酸酯的合成用途。
Design of an organic sequence suitable for the solid phase combinatorial synthesis of libraries of macro-heterocycles
作者:Mahesh Ramaseshan、John W Ellingboe、Yves L Dory、Pierre Deslongchamps
DOI:10.1016/s0040-4039(00)00710-3
日期:2000.6
The solid as well as solution phasesynthesis of two 14-membered macro-heterocycles is reported. The macrocycles are built out of four or three major building blocks and contain serine, a trans alkene and the malonate unit inside the framework. The macrocyclization was an SN2 reaction between a nucleophilic malonate anion and an allylic chloride leaving group. The first macrocycle, an ether, was obtained
Fuel composition comprises (a) 15 to 60% by weight, preferably 40 to 55%, of a friable solid fuel, e.g. coal, (b) a stabilising additive composition and (c) a fuel oil. The additive comprises the combination of a polymer containing functional groups, e.g., maleinised polybutadiene, and a surfactant. The composition is suitable for use as a liquid fuel for industrial burners.
Fluorinated arachidonic derivatives are 5-lipoxygenase inhibitors which have the useful pharmacologic activity as antiallergy and anti-inflammatory agents and are useful for treating, for example, asthma, anaphylaxis, allergy, rheumatoid arthritis, and psoriasis and cardiovascular diseases.