Synthesis of multiple boron-containing analogs via Ugi-4CR

Research on Chemical Intermediates - One of the most significant challenges in boron neutron capture therapy (BNCT) is to have an ideal boron delivery agent which can deliver sufficient numbers of...     

Synthesis of novel indolo[2,3-c]quinolinones via Ugi-4CR/palladium-catalyzed arylation

In this letter, an expedient method was developed for the construction of novel indolo[2,3-c]quinolinone derivatives via palladium-catalyzed arylation of Ugi adducts obtained from the reaction of indole-2-carboxylic acid, various aromatic aldehydes, 2-bromoanilines, and isocyanides. The reaction proceeded efficiently with various starting materials to produce the indoloquinolinone scaffolds in good yields.     

Synthesis of Dibenzo[b,e]azepin-6(11H)-ones via a Sequential Ugi-4CR and Sulfur Ylide-Mediated Rearrangement Reaction

A new one-pot preparation of dibenzo[b,e]azepin-6(11H)-one by a sequential Ugi-4CR and sulfur ylide-mediated rearrangement reaction has been developed. A series of polysubstituted dibenzo[b,e]azepin-6(11H)-ones were obtained in 69–84 % yields from readily available sulfonium salts, 2-aminophenyl ketones, aldehydes and isocyanides in the presence of DBU.     

Synthesis of 2-amino-4-phenylthiazole under conditions of microwave irradiation

The possibility of preparing 2-amino-4-phenylthiazole from acetophenone, iodine, and thiourea under the conditions of microwave irradiation was studied.     

Synthesis of polyacetals under microwave irradiation

Synthesis of polyvinyl formal from a mixture of polyvinyl alcohol and formaldehyde under microwave irradiation was studied. The syntheses of polyvinyl formal under microwave irradiation and thermal treatment were compared. The yield of polyvinyl formal was examined in relation to the irradiation power, initial component concentration, and reaction time. The polyacetals were characterized by elemental analysis and IR spectroscopy.     

微波辐射下的芳基甲酰氨基硫脲的合成

本文报道了以水为介质, 在微波辐射下的芳基甲酰氨基硫脲的合成。该法反应快, 产率高。     

Synthesis of 5-aryltriazole ribonucleosides via Suzuki coupling and promoted by microwave irradiation

Aryltriazole nucleosides with various aromatic groups in the 5-position on the triazole ring were synthesized and characterized with the aim to develop novel triazole nucleosides. The aromatic groups were introduced into the triazole ring via a Suzuki reaction starting with bromotriazole nucleoside. Microwave irradiation significantly promoted the Suzuki coupling, quickly giving clean products with good to excellent yields.     

Synthesis of novel 2,3-dihydro-4-pyridinones from bisdemethoxycurcumin under microwave irradiation

A novel synthesis of 2,3-dihydro-4-pyridinones via the reaction of bisdemethoxycurcumin and primary amines or amine acetates is demonstrated. The structures of the products were established by elemental analysis and from mass, ¹H and ¹³C NMR spectra.     

Synthesis of thiazolines by the reaction of aryl ketonitriles with cysteamine via microwave irradiation

Thiazolines were synthesized in a one‐pot reaction in excellent yield using a newly developed methodology. Ketonitriles were directly condensed with cysteamine (2‐amino‐thioalcohol) via microwave irradiation at 210°C for 10 minutes under solvent free conditions and without any solid support. All the compounds were characterized by ¹H nmr, ¹³C nmr spectroscopy and elemental analyses.     

Solid-phase synthesis of natural product-like macrocycles by a sequence of Ugi-4CR and SNAr-based cycloetherification

An on-resin Ugi four-component reaction followed by an intramolecular nucleophilic aromatic substitution (S_NAr) has been developed for the rapid access to biaryl-ether containing macrocycles.     

微波合成水杨酸异丙酯

研究了微波合成水杨酸异丙酯的工艺，与常规方法相对比，发现利用微波合成 水杨酸异丙酯具有反应速度快、转化率高、杂质含量小、后处理简单、无三废排放 等优点。     

微波辐射下苯并(口恶)唑基吡啶的合成

含有苯并唑基的杂环化合物由于其特殊的生理活性而广泛用作医药、农药[1];因为具有较高的荧光量子产率,还可作为荧光增白剂、闪烁剂[2]等。现有合成方法反应时间长[3,4],而且需高温下进行。微波辐射下的有机合成具有反应时间短、产率高的特点[5]。本文在微波辐射条件下,利用邻氨基酚和吡啶羧酸的缩合反应,合成了2种苯并唑基取代吡啶。其优化反应条件为:多聚磷酸为催化剂,微波输出功率为500W,辐射时间4分钟。相比于常规反应,该条件下的反应速率是常规加热法反应速率的60倍且产率有所提高。合成路线如下:ppA=Polyphosphoricacid1　…     

Direct synthesis of unprotected 4-aryl phenylalanines via the Suzuki reaction under microwave irradiation

[formula: see text] 4-Aryl phenylalanines were prepared as free amino acids from the Suzuki coupling of 4-borono phenylalanine with aryl halides in high yields within 5-10 min under microwave irradiation.     

Chiral Nβ-Fmoc-amino alkyl isonitriles in Ugi-4CR: an assembly of novel 1,1′-iminodicarboxylated peptidomimetics

Enantiopure N^β-Fmoc-amino alkyl isonitriles and amino acid esters have been employed as building blocks in Ugi four-component reaction (U-4CR) to yield 1,1′-iminodicarboxylated peptidomimetics. By employing trifluoroacetic acid as one of the components, a different outcome has been observed and rationalized. Ugi products are obtained as trifluoroacetamide adducts, which on further reaction under mild acidic conditions lead to the title compounds. The method has also been proven to be useful for the preparation of ethyl, benzyl and tert-butyl esters.     

Palladium-catalyzed intramolecular C-arylation of benzylic carbon: synthesis of 3-benzoxazolylisoindolinones by a sequence of Ugi-4CR/postfunctionalization

Submitting Ugi-adduct 4 to two consecutive metal-catalyzed intramolecular reactions, namely copper-catalyzed O-arylation and palladium-catalyzed C-arylation of benzylic carbon developed in the course of this study, affords the benzoxazolylisoindolinones in good to excellent yields.     

Efficient Pd-catalyzed synthesis of 2-arylaminopyrimidines via microwave irradiation

An efficient method for the synthesis of 2-arylaminopyrimidines via microwave assisted, Pd-mediated amination of 2-chloropyrimidine is reported. This method is superior to the classical heating process, particularly when one of starting materials is a heteroarylamine.     

二茂铁基1,4-Dihydropyridine类似物的合成

1 ,4 二氢吡啶衍生物是一类有着多种生物活性的化合物 ,具有扩张血管、抗高血压、抗动脉粥状硬化、抗肿瘤、抗糖尿病、抗衰老等作用 ,是七十年代以来相继开发的一类新型高效的钙离子拮抗剂 ,临床上用于治疗高血压、心绞痛、充血性心衰和动脉粥状硬化等心脑血管疾病及肠胃疾病、雷诺氏病 ,还可以作为辅佐药物治疗肺动脉高压和癫痫病[1 ] 。近年来 ,二茂铁衍生物在生物学、医学等方面得到了广泛的研究和应用 ,主要是由于它们的结构和性质有自身的特殊性 :二茂铁有卓越的芳香性 ,易发生取代反应 ,易进行修饰 ,并且在许多介质中有较好的稳定性 ;…     

Synthesis of pyrimidines from ketones using microwave irradiation

A simple, high yielding synthesis of pyrimidines from ketones in the presence of HMDS and formamide is described. Under microwave irradiation, heteroaromatic, aryl, aliphatic, and cyclic ketones cyclized to give pyrimidines in good yields.     

Synthesis of 4-substituted-1,2,3-triazole carbanucleoside analogues of ribavirin via click chemistry

The synthesis and biological evaluation as antiviral agents of a series of racemic 4-aryl-1,2,3-triazolo-2',3'-dideoxy-2'-iodocarbanucleosides and 4-aryl-1,2,3-triazolo-2',3'-dideoxy-2',3'-didehydrocarbanucleosides is presented. These compounds were produced using a click chemistry approach, with the iodoazide 13a as the key intermediary.     

Facile synthesis of new 1,2,3-benzotriazolo-2-oxo-azetidine analogues by microwave irradiation

A series of new N¹-[3-{(4-subtitutedaryl-3-chloro-2-oxo-azetidine)-carbamyl}-propyl]-1,2,3-benzotriazoles 4(a–s) have been synthesized from 1,2,3-benzotriazole as a starting material by microwave method. The structures of all the synthesized compounds were confirmed by chemical and spectral analyses such as IR, ¹H NMR, ¹³C NMR and FAB-Mass.