绿色合成：一个逐步形成的学科前沿

绿色合成是有机合成化学面向新世纪的学科前沿。本文探讨绿色合成的目标及实现这一目标的一些可能途径。     

Divergent strategy in natural product total synthesis

Divergent strategy in natural product synthesis allows the comprehensive synthesis of family natural products. Efficient formulation of this idea requires the biosynthetic/biosynthesis-inspired insight toward the well-orchestrated design of a pluripotent late-stage intermediate, in concomitant with the applicability of the intermediates for versatile transformations. This digest focuses on the actual applications of those strategies in natural product synthesis with an emphasis on the recipes for the choice of the common intermediates.     

Nitrogen-Containing Six-Membered Heterocycles: Solid-Phase Synthesis

Solid-phase organic synthesis is a rapidly expanding area of synthetic chemistry that is being widely exploited in the search for new medicinally important compounds using combinatorial techniques. In recent decades, a large number of reports related to solid-phase synthesis of heterocycles have appeared because of the wide variety of their biological activity. In this review, we report the important role of solid-phase synthesis in the synthesis of nitrogen containing six-membered ring heterocycles.     

微波辅助组合合成的研究进展

微波辅助组合合成技术是近年来发展起来的一种新的制备化合物库的组合化学技术, 它不仅可以克服传统固相组合合成技术以及液相组合合成技术无法提高产物收率的不足, 而且利用该技术所制得的化合物库中对应的是高纯度的单一化合物, 采用高通量筛选技术可以快速直接地确定高活性结构, 极大地提高了新药开发的效率. 主要就近年来微波辅助组合合成技术的研究进展情况进行介绍, 内容包括固相组合合成、基于聚合物支载的催化剂的组合合成、液相组合合成、氟相组合合成以及组合平行合成等.     

Flow “Fine” Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods

The concept of flow “fine” synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow “fine” synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society.     

Solid-Phase-Supported Chemoenzymatic Synthesis of a Light-Activatable tRNA Derivative

Herein, we present a multi-cycle chemoenzymatic synthesis of modified RNA with simplified solid-phase handling to overcome size limitations of RNA synthesis. It combines the advantages of classical chemical solid-phase synthesis and enzymatic synthesis using magnetic streptavidin beads and biotinylated RNA. Successful introduction of light-controllable RNA nucleotides into the tRNA^Met sequence was confirmed by gel electrophoresis and mass spectrometry. The methods tolerate modifications in the RNA phosphodiester backbone and allow introductions of photocaged and photoswitchable nucleotides as well as photocleavable strand breaks and fluorophores.     

Rapid and convenient semi-automated microwave-assisted solid-phase synthesis of arylopeptoids

A facile and expedient route to the synthesis of arylopeptoid oligomers (N-alkylated aminomethyl benz-amides) using semi-automated microwave-assisted solid-phase synthesis is presented. The synthesis was optimized for the incorporation of side chains derived from sterically hindered or unreactive amines and both ortho- and para-substituted arylo-backbones. By utilizing this optimized protocol a complex nonameric arylopeptoid was synthesized in less than 11 h, featuring a novel alternating ortho-, meta-, and para-substituted backbone pattern and a variety of chemically diverse and challenging side chains.     

Solid-Phase Synthesis of Nitrogen-Containing Five-Membered Heterocycles

In recent decades, a large number of reports related to solid-phase synthesis of heterocycles have appeared, owing to the wide variety of their biological activity. This review introduces the key concepts of solid-phase methodology and combinatorial synthesis with particular focus on the important role of solid-phase synthesis in the synthesis of nitrogen-containing five-membered ring heterocycles.     

Solid-Phase Synthetic Approach Toward the Synthesis of Oxygen-Containing Heterocycles

Solid-phase organic synthesis is a rapidly expanding area of synthetic chemistry which is being widely exploited in the search for new medicinally important compounds using combinatorial techniques. In recent decades, a large number of reports related to solid-phase synthesis of heterocycles have appeared because of the wide variety in their biological activity. In this review, we report the important role of solid-phase synthesis in the synthesis of oxygen-bearing heterocycles.     

片呐醇的绿色合成

综述了近年来片呐醇绿色合成研究的新进展,主要包括微波、超声波、固相合成、电合成、光化学合成等新技术、新试剂在该反应中的应用。     

片呐醇的绿色合成

综述了近年来片呐醇绿色合成研究的新进展，主要包括微波、超声波、固相合成、电合成、光化学合成等新技术、新试剂在该反应中的应用。     

不对称有机合成和反应的分类

不对称有机合成和反应是制备对映纯化合物的方法之一,它具有广泛而不同的含义。对基于反应产物的“立体选择合成”,基于反应物的“立体辨别反应”和“去对称”以及基于不对称诱导方式的“代”分类方法作了介绍和评述。另外,对几个与不对称合成有关的制备对映纯化合物的方法也作了阐述。对“双重不对称合成”的立体化学,以Michael反应为例进行了讨论。参考文献34篇。     

液相组合合成研究进展

综述了近年来液相组合合成的研究进展,主要包括液相组合合成法(LPCS),氟合成,树状载体组合合成及高分子辅助试剂在液相组合合成中的应用等。     

酸性条件下纯硅六方介孔分子筛的合成(Ⅱ)合成温度、时间的影响及其与碱性合成的比较

本文以十六烷基三甲基溴化铵为模板剂,正硅酸乙酯为硅源,考察了反应温度和时间对酸性条件下合成纯硅六方介孔分子筛的影响,并与碱性合成路径相比较。结果表明,由于无机物种与表面活性剂之间的相互作用不同,六方介孔分子筛的酸性合成经历了与碱性合成完全不同的机理。对要到性合成来说,由于六方结构的形成取决于稳定的模板胶束的存在,并不特别依赖于硅物种的缩合,故高温、长反应时间等有利于缩合的因素对提高产品质量几乎没有促进作用,较高的反应温度甚至起反作用。因此,酸性合成宜采用室温条件。     

Total Synthesis of (−)‐Ophiodilactone A and (−)‐Ophiodilactone B

The first asymmetric total synthesis of (?)‐ophiodilactone A and (?)‐ophiodilactone B, isolated from the ophiuroid (Ophiocoma scolopendrina), is reported. The key features of the synthesis include the highly stereocontrolled construction of the structurally congested γ‐lactone/δ‐lactone skeleton through an asymmetric epoxidation, diastereoselective iodolactonization, and intramolecular epoxide‐opening with a carboxylic acid, and biomimetic radical cyclization of ophiodilactone A to ophiodilactone B.     

Chichibabin “isodesmopyridine” synthesis

2,3,5-Trisubstituted pyridine isodesmopyridine is one of the elastin crosslinking amino acid which was isolated from the acid hydrolysates of bovine ligamentum nuchae. Biosynthesis of isodesmopyridine is believed to undergo via Chichibabin pyridine synthesis starting from aldehydes and an ammonia. Herein, we report the first total synthesis of isodesmopyridine through Chichibabin pyridine synthesis from allysines with protecting groups and ammonium salts in the presence of 50?mol% Pr(OTf)₃ with the optimization of the reaction conditions.     

亚砜亚胺类化合物的合成及应用研究进展

亚砜亚胺(Sulfoximine)类化合物是一类重要的杂原子取代化合物,引起了人们的广泛关注.综述了近十年来亚砜亚胺类化合物的研究进展,包括该类化合物的合成及在不对称催化领域中的应用、含有亚砜亚胺的生物活性小分子合成和天然产物全合成.并对发展趋势和应用前景做了展望.     

钼原子簇合成化学研究──（Ⅰ）一些单核钼化合物的自兜反应和成簇反应规律

本文是作者在钼原子簇合成化学研究的综合性报导，包括自兜合成和设计合成两个部分。这一部分概述了一些Ｍｏ（＋３）～Ｍｏ（＋６）单核化合物在Ｃｌ~－、Ｓ~（２－）、ＣＨ_３ＣＯ_２~－和（ＥｔＯ）ＰＳ_２~－等配基参与下的自兜反应及其产物，总结了成簇的某些规律。包括Ｍｏ原子的价态，μ－桥基的种类，介质的酸度对所形成的簇合物的影响。反应中卤原子的交换现象，以及和ＲＣＯ_２~－（ＥｔＯ）_２ＰＳ_２~－两种双齿配基的配位特点。讨论了自兜合成方法的局限性。     

Metal-free and azide-free synthesis of 1,2,3-triazoles derivatives

1,2,3-Triazoles, significant five-membered ring N-heterocycles, are main structural moieties in well-designed materials, pharmaceutical agents, bioactive products, and synthetic intermediates. In the research of life sciences and pharmaceuticals, by seeing the spacious applications of 1,2,3-triazoles, the progress of metal-free method is exceedingly desirable to evade the heterocyclic product metal contamination. Moreover, on a larger scale, the toxicity and explosiveness of azides makes azides discommode and hard to hold, to synthesize 1,2,3-triazoles. The need to steer the development of the synthesis of 1,2,3-triazoles toward more maintainable synthesis is a pressing issue. There are rare methods to construct 1,2,3-triazoles under azide-free and metal-free environments. These rare methods are compiled in this review. The afford of the collection and compilation of azide-free and metal-free synthesis methodologies of 1,2,3-triazole in single podium is supportive and crucial for synthetic chemist to extend the diversity of the synthesis of 1,2,3-trizoles through green protocol.     

Stereoselective Halogenation in Natural Product Synthesis

At last count, nearly 5000 halogenated natural products have been discovered. In approximately half of these compounds, the carbon atom to which the halogen is bound is sp³‐hybridized; therefore, there are an enormous number of natural products for which stereocontrolled halogenation must be a critical component of any synthesis strategy. In this Review, we critically discuss the methods and strategies used for stereoselective introduction of halogen atoms in the context of natural product synthesis. Using the successes of the past, we also attempt to identify gaps in our synthesis technology that would aid the synthesis of halogenated natural products, as well as existing methods that have not yet seen application in complex molecule synthesis. The chemistry described herein demonstrates yet again how natural products continue to provide the inspiration for critical advances in chemical synthesis.