碳一化工路线制备乙二醇研究进展

乙二醇(EG)是一种重要的化工原料,主要用来生产新型聚酯纤维.近年来由于我国聚酯产业发展迅速,极大的推动了对乙二醇的需求.碳一化工路线以资源丰富、价格便宜的天然气或煤为原料合成乙二醇,有着诱人的工业化前景.综述了以合成气为原料合成乙二醇的研究进展,包括合成气直接合成法、甲醛羰化法、CO偶联法、甲醛氢甲酰化法以及甲醛缩合法等.     

Rapid synthesis of a glycosylphosphatidylinositol-based malaria vaccine using automated solid-phase oligosaccharide synthesis

Described is an automated synthesis of hexasaccharide malarial toxin 1, currently under development as a malaria vaccine candidate. Using a combination of automated solid-phase methods and solution-phase fragment coupling, the target glycosylphosphatidylinositol was assembled in a matter of days, compared with several weeks for a comparable solution-phase synthesis.     

Diverse 2-carboxamide-3-amino-substituted quinoxalines: synthesis and reactivity investigation for library generation

Described herein is the development of a robust synthetic route applicable to parallel synthesis of diverse 2-carboxamide-3-amino-substituted quinoxalines. In addition to the scope and limitations of the methods developed, a purification strategy employing solid-phase extraction (SPE) and application of the methods to a small parallel array of compounds are discussed.     

生物可降解性聚羟基脂肪酸酯的化学合成研究进展

聚羟基脂肪酸酯是一种新型合成的脂肪族聚酯,同聚乳酸相似,具有优异的生物相容性能、生物可降解性和优良的力学机械性能,可作为生物医用材料和生物可降解包装材料,是最具前景的环境友好型聚合材料之一。目前合成聚乳酸和聚羟基脂肪酸酯的化学方法主要有开环聚合法、直接缩聚法以及自身酯交换聚合法,不过后者研究得较少。本文对这3种方法的研究进展进行了叙述,重点讨论了开环聚合法和直接缩聚法,尤其对开环聚合中的配位插入聚合的新进展进行了较详细的论述。     

Carbon‐Monoxide‐Releasing Molecules for the Delivery of Therapeutic CO In Vivo

The development of carbon‐monoxide‐releasing molecules (CORMs) as pharmaceutical agents represents an attractive and safer alternative to administration of gaseous CO. Most CORMs developed to date are transition‐metal carbonyl complexes. Although such CORMs have showed promising results in the treatment of a number of animal models of disease, they still lack the necessary attributes for clinical development. Described in this Minireview are the methods used for CORM selection, to date, and how new insights into the reactivity of metal‐carbonyl complexes in vivo, together with advances in methods for live‐cell CO detection, are driving the design and synthesis of new CORMs, CORMs that will enable controlled CO release in vivo in a spatial and temporal manner without affecting oxygen transport by hemoglobin.     

From Alkyl Halides to Ketones: Nickel‐Catalyzed Reductive Carbonylation Utilizing Ethyl Chloroformate as the Carbonyl Source

Ketones are an important class of molecules in synthetic and medicinal chemistry. Rapid and modular synthesis of ketones remains in high demand. Described here is a nickel‐catalyzed three‐component reductive carbonylation method for the synthesis of dialkyl ketones. A wide range of both symmetric and asymmetric dialkyl ketones can be accessed from alkyl halides and a safe CO source, ethyl chloroformate. The approach offers complementary substrate scope to existing carbonylation methods while avoiding the use of either toxic CO or metal carbonyl reagents.     

酶催化生物可降解聚酯的合成与研究进展

生物可降解聚酯是一种新型高分子聚合材料,可通过发酵、化学方法和酶催化来合成.本文综述了酶催化下通过缩聚、酯交换、内酯开环聚合等方法合成此类聚酯.酶催化合成生物可降解聚酯是一种新型的技术,可以在温和条件下高效合成,有着传统方法难以比拟的优势.     

Visible-Light Photocatalytic Intramolecular Cyclopropane Ring Expansion

Described herein is a new visible-light photocatalytic strategy for the synthesis of enantioenriched dihydrofurans and cyclopentenes by an intramolecular nitro cyclopropane ring expansion reaction. Mechanistic studies and DFT calculations are used to elucidate the key factors in this new ring expansion reaction, and the need for the nitro group on the cyclopropane.     

Visible‐Light Photocatalytic Intramolecular Cyclopropane Ring Expansion

Described herein is a new visible‐light photocatalytic strategy for the synthesis of enantioenriched dihydrofurans and cyclopentenes by an intramolecular nitro cyclopropane ring expansion reaction. Mechanistic studies and DFT calculations are used to elucidate the key factors in this new ring expansion reaction, and the need for the nitro group on the cyclopropane.     

Biocatalytic Friedel–Crafts Acylation and Fries Reaction

The Friedel–Crafts acylation is commonly used for the synthesis of aryl ketones, and a biocatalytic version, which may benefit from the chemo- and regioselectivity of enzymes, has not yet been introduced. Described here is a bacterial acyltransferase which can catalyze Friedel–Crafts C-acylation of phenolic substrates in buffer without the need of CoA-activated reagents. Conversions reach up to >99 %, and various C- or O-acyl donors, such as DAPG or isopropenyl acetate, are accepted by this enzyme. Furthermore the enzyme enables a Fries rearrangement-like reaction of resorcinol derivatives. These findings open an avenue for the development of alternative and selective C−C bond formation methods.     

Enantioselective Allylic Hydroxylation of ω‐Alkenoic Acids and Esters by P450 BM3 Monooxygenase

Chiral allylic alcohols of ω‐alkenoic acids and derivatives thereof are highly important building blocks for the synthesis of biologically active compounds. The direct enantioselective C? H oxidation of linear terminal olefins offers the shortest route toward these compounds, but known synthetic methods are limited and suffer from low selectivities. Described herein is an enzymatic approach using the P450 BM3 monooxygenase mutant A74G/L188Q, which catalyzes allylic hydroxylation with high to excellent chemo‐ and enantioselectivities providing the desirable secondary alcohols.     

Biocatalytic Friedel–Crafts Acylation and Fries Reaction

The Friedel–Crafts acylation is commonly used for the synthesis of aryl ketones, and a biocatalytic version, which may benefit from the chemo‐ and regioselectivity of enzymes, has not yet been introduced. Described here is a bacterial acyltransferase which can catalyze Friedel–Crafts C‐acylation of phenolic substrates in buffer without the need of CoA‐activated reagents. Conversions reach up to >99 %, and various C‐ or O‐acyl donors, such as DAPG or isopropenyl acetate, are accepted by this enzyme. Furthermore the enzyme enables a Fries rearrangement‐like reaction of resorcinol derivatives. These findings open an avenue for the development of alternative and selective C−C bond formation methods.     

Anticancer anilinoacridines. A process synthesis of the disubstituted amsacrine analog CI-921

An improved process for the synthesis of bulk quantities of the clinical amsacrine analog CI-921 is reported. Described also are detailed analytical and spectroscopic data for this agent.     

Synthesis and characterization of highly fluorescent indenofluorenes

[structure: see text] Described here are the synthesis and optical and electrochemical properties of a series of indenofluorenes as new building blocks for electronic and optoelectronic materials.     

二氧化硫脲的制备及其在有机合成中的应用

本文简要论述了二氧化硫脲的特性、制备方法及其作为新型还原剂在有机合成中的应用。     

Fabrication of thermoset polyester microfluidic devices and embossing masters using rapid prototyped polydimethylsiloxane molds

Plastics are increasingly being used for the fabrication of Lab-on-a-Chip devices due to the variety of beneficial material properties, affordable cost, and straightforward fabrication methods available from a range of different types of plastics. Rapid prototyping of polydimethylsiloxane (PDMS) devices has become a well-known process for the quick and easy fabrication of microfluidic devices in the research laboratory; however, PDMS is not always an appropriate material for every application. This paper describes the fabrication of thermoset polyester microfluidic devices and masters for hot embossing using replica molding techniques. Rapid prototyped PDMS molds are convienently used for the production of non-PDMS polymeric devices. The recessed features in the cast polyester can be bonded to a second polyester piece to form an enclosed microchannel. Thermoset polyester can withstand moderate amounts of pressure and elevated temperature; therefore, the cast polyester piece also can be used as a master for embossing polymethylmethacrylate (PMMA) microfluidic systems. Examples of enclosed polyester and PMMA microchannels are presented, and we discuss the electroosmotic properties of both types of channels, which are important for analytical applications such as capillary electrophoresis.     

Method for the synthesis of multi-epitopic Streptococcus pyogenes lipopeptide vaccines using native chemical ligation

The aim of this study was to investigate methods for the synthesis of highly pure, well-characterized analogues of the lipid core peptide (LCP) system. Difficulties synthesizing and purifying conventional LCP systems have led to the requirement for a technique to produce highly pure, LCP-based vaccines for potential use in human clinical trials. The current study describes methods for the attachment of lipophilic adjuvants onto multi-epitopic peptide vaccines. Described is the synthesis, using native chemical ligation, of a highly pure, tri-epitopic, group A streptococcal (GAS) lipopeptide vaccine candidate. Intranasal immunization of the described tri-epitopic GAS lipopeptide with the mucosal adjuvant cholera toxin B subunit induced high serum IgG antibody titers specific for each of the incorporated peptide epitopes.     

Versatile In Situ Generated N‐Boc‐Imines: Application to Phase‐Transfer‐Catalyzed Asymmetric Mannich‐Type Reactions

The efficient construction of nitrogen‐containing organic compounds is a major challenge in chemical synthesis. Imines are one of the most important classes of electrophiles for this transformation. However, both the available imines and applicable nucleophiles for them are quite limited given the existing preparative methods. Described herein are imine precursors which generate reactive imines with a wide variety of substituents under mild basic conditions. This approach enables the construction of various nitrogen‐containing molecules which cannot be accessed by the traditional approach. The utility of the novel imine precursor was demonstrated in the asymmetric Mannich‐type reaction under phase‐transfer conditions.     

Cross‐Coupling of Alkyl Redox‐Active Esters with Benzophenone Imines: Tandem Photoredox and Copper Catalysis

Alkyl amines are an important class of organic compounds in medicinal and materials chemistry. Until now very have been very few methods for the synthesis of alkyl amines by metal‐catalyzed cross‐coupling of alkyl electrophiles with nitrogen nucleophiles. Described here is an approach to employ tandem photoredox and copper catalysis to enable the cross‐coupling of alkyl N‐hydroxyphthalimide esters, readily derived from alkyl carboxylic acids, with benzophenone‐derived imines. Hydrolysis of the coupling products furnish alkylated primary amines. Primary, secondary, and tertiary alkyl groups can be transferred, and the coupling tolerates a diverse set of functional groups. The method allows rapid functionalization of natural products and drugs, and can be used to expedite syntheses of pharmaceuticals from readily available chemical feedstocks.