A Highly Efficient Strategy for One-Pot and Pseudo-Six-Component Synthesis of Hexahydroquinolines.

In this study, a homogeneous acid-catalyzed reaction of a series of benzaldehydes, benzylamines, and Meldrum's acid was presented, allowing the novel one-pot and multicomponent synthesis of hexahydroquinolines with high stereoselectivity. The current strategy has advantages including high regioselectivity, good efficiency, reasonable diversity, utilization of an inexpensive and safe catalyst, and easy purification of products by simple recrystallization. The current reaction utilizes 2 equiv of Meldrum's acid, 3 equiv of benzaldehyde derivatives, and one equiv of amine derivatives to yield (4'S,5'S,7'S)-1'-benzyl-2,2-dimethyl-4',5',7'-triphenyl-3',4',7',8'-tetrahydro-1'H-spiro[[1,3]dioxane-5,6'-quinoline]-2',4,6(5'H)-trione derivatives.

A versatile approach for one-pot synthesis of hybridized quinolines linked to fused N-containing heterocycles in water.

Here, highly efficient one-pot protocols for the synthesis of structurally diverse fused N-containing heterocycles containing 2-chloroquinoline employing 1,1-bis(methylsulfanyl)-2-nitroethene, diamines, 2-chloroquinoline-3-carbaldehydes and dimedone/Meldrum's acid in green media in the absence of catalyst are reported. The current report proposes sustainable, simple, four-component and straightforward strategies for generating interesting N-containing heterocyclic compounds from a range of diamines and 2-chloroquinoline-3-carbaldehydes. The utilization of water as green media furnishes sustainability by preventing the usage of toxic solvent. A range of quinoline-containing aldehydes and diamines can be converted to two types of products with respect to using dimedone or Meldrum's acid via an inexpensive, one-pot and easy route.

Recent Strategies in Transition-Metal-Catalyzed Sequential C-H Activation/Annulation for One-Step Construction of Functionalized Indazole Derivatives.

Designing new synthetic strategies for indazoles is a prominent topic in contemporary research. The transition-metal-catalyzed C-H activation/annulation sequence has arisen as a favorable tool to construct functionalized indazole derivatives with improved tolerance in medicinal applications, functional flexibility, and structural complexity. In the current review article, we aim to outline and summarize the most common synthetic protocols to use in the synthesis of target indazoles via a transition-metal-catalyzed C-H activation/annulation sequence for the one-step synthesis of functionalized indazole derivatives. We categorized the text according to the metal salts used in the reactions. Some metal salts were used as catalysts, and others may have been used as oxidants and/or for the activation of precatalysts. The roles of some metal salts in the corresponding reaction mechanisms have not been identified. It can be expected that the current synopsis will provide accessible practical guidance to colleagues interested in the subject.

A Quick Access to Structurally Diverse Triazoloquinazoline Heterocycles via the MIL-101(Cr)-Catalyzed One-Pot Multi-Component Reaction of a Series of Benzaldehydes, Dimedone, and 1H-1,2,4-Triazol-3-Amine Under Green Conditions.

A one-pot multicomponent reaction of a variety of benzaldehydes, dimedone, and 1H-1,2,4-triazol-3-amine for the efficient synthesis of quinazolinone derivatives under green conditions is reported. It was proved that MIL-101(Cr) could carry out successfully this multicomponent strategy to afford target products in high yields. The scope and limitation of this catalytic system concerning the aldehyde substrates were explored. Different aldehydes could be conveniently delivered to quinazolinones at room temperature with short reaction times in an atom-economy way. Notably, MIL-101(Cr) was also characterized by different analytic methods such as FT-IR, SEM, and EDX. The outstanding benefits of this methodology are the availability of substrates, using green conditions, excellent functional group compatibility, and reusability of catalysts, therefore providing easy access to a range of products of interest in organic and medicinal chemistry.

A patent review on efficient strategies for the total synthesis of pazopanib, regorafenib and lenvatinib as novel anti-angiogenesis receptor tyrosine kinase inhibitors for cancer therapy.

Angiogenesis is an important and interesting scientific subject in the area of malignant tumours. Current research importance and interest are directed in connection to blood microvessels in cancer cell proliferation, tumour growth, and metastasis. Tyrosine kinases have been intensely implicated as therapeutic targets that affect the angiogenic process in tumour growth. In the last decades, targeting angiogenesis has led to achievements in the therapy of different carcinomas by different mechanisms, such as the utilization of anti-angiogenic small molecule receptor tyrosine kinase inhibitors. In the current review, we aim to track the advancements in the total synthesis of three receptor tyrosine kinase inhibitors (pazopanib, regorafenib and lenvatinib). This review surveys different synthetic routes for these three approved drugs (pazopanib, regorafenib and lenvatinib) which were previously published as patents (2014-2021). The purity of medicines is a very important factor during manufacturing so we have decided to review the purification process of these anticancer medicines as well. It should be noted that the different patents may have reported some procedures with different yields and purities for the synthesis of desired drug and their intermediates. In order to simplify the understanding of the contents of this review article, only the best results reported in each of these patents are reported for the synthesis of desired drug and their intermediates.

Supported Cu(II)-Schiff base: novel heterogeneous catalyst with extremely high activity for eco-friendly, one-pot and multi-component C-S bond-forming reaction toward a wide range of thioethers as biologically active cores.

An effective and proficient process for the synthesis of a variety of thioethers via the one-step reaction of benzyl halides, aryl halides, and thiourea is presented. This strategy is a one-pot procedure to achieve a variety of thioethers without the requirement to thiols as starting compounds. A range of thioethers containing electron donating/electron-withdrawing functional groups were obtained with good to excellent yields under mild conditions. Moreover, the nanocatalyst exhibited excellent recyclability for the reaction, making it more sustainable. One-pot and multi-component synthesis, high yields of final products, green reaction media, high activity of nanocatalyst, simple separation of the products and catalyst, and high regioselectivity are several highlights of this method.

A recent overview on the synthesis of 1,4,5-trisubstituted 1,2,3-triazoles.

Diverse strategies for the efficient and attractive synthesis of a wide variety of relevant 1,4,5-trisubstituted 1,2,3-triazole molecules are reported. The synthesis of this category of diverse fully functionalized 1,2,3-triazoles has become a necessary and unique research subject in modern synthetic organic key transformations in academia, pharmacy, and industry. The current review aims to cover a wide literature survey of numerous synthetic strategies. Recent reports (2017-2021) in the field of 1,4,5-trisubstituted 1,2,3-triazoles are emphasized in this current review.

Highly selective fluorescent peptide-based chemosensors for aluminium ions in aqueous solution.

Two novel fluorescent peptide-based chemosensors, including A (2-amino-benzoyl-Ser-Glu-Glu-NH2) and B (2-amino-benzoyl-Ala-Glu-Pro-Glu-Ala-Glu-Pro-NH2) were synthesized and characterized by nuclear magnetic resonance (NMR) spectra. These fluorescent probes exhibited excellent selective and sensitive responses to Al3+ ions over other metal ions in aqueous buffered solutions. The limits of detection for both chemosensors towards the Al3+ ions were in the order of ∼10-7 M (A: 155 nM and B: 195 nM), which clearly indicates that these probes have significant potential for biological applications. They also displayed high binding affinity (1.3029 × 104 M-1 and 1.7586 × 104 M-1 relevant to A and B respectively). These two chemosensors are great analytical probes that produce turn-on responses upon binding to Al3+ ions through an intramolecular charge transfer (ICT) mechanism. In addition, the application of both chemosensors was examined over a wide range of pH. The fluorescent peptide-based probes and Al3+ form a 1:1 coordination complex according to the ESI-MS and Job's plot analysis. Notably, upon addition of Al3+ to these chemosensors, a fluorescence enhancement of approximately 8-fold was observed and the binding mode was determined using NMR titration and fluorescence emission data.

Novel Hybrid Molecules Based on triazole-ß-lactam as Potential Biological Agents.

Triazole ring is a cyclic scaffold containing three heteroatoms of nitrogen. They display a broad variety of biological activities. The uncatalyzed/catalyzed 1,3-dipolar cycloadditions are a chemical reaction between a 1,3-dipole and a dipolarophile to achieve 1,2,3-triazoles. The hybrid approach is an innovative and powerful synthetic tool for the synthesis of two or more distinct entities in one molecule with novel biological activities. Owing to the high potential of ß-lactams to display noticeable biological properties, these compounds have been one of the important ingredients in hybrid molecules. The four-membered lactams have been recognized as a part of penicillin. There are various synthetic protocols for the synthesis of ß-lactams. Staudinger reaction of the Schiff bases with diphenylketenes is a successful and famous strategy for the synthesis of these products. Even though, the number of heterocyclic compounds is limited, plenty of hybrids based on heterocyclic compounds can be designed and prepared. The synthesis of hybrid products of triazole-ß-lactam has proved to be highly challenging. The current review article outlines the diversity and creativity in the elegant synthesis of triazole-ß-lactam hybrids as potential biological agents. Molecules including isatin, ferrocene, bile acid, chalcone, and etc were attached to ß-lactam with triazole linker, as well.

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in "click" reactions.

In recent years, many inorganic silica/carbon-based and magnetic materials have been selected to arrest copper ions through a widespread range of anchoring and embedding methodologies. These inorganic supported nanocatalysts have been found to be efficient, environmentally friendly, recyclable, and durable. In addition, one of the vital issues for expanding new, stable, and reusable catalysts is the discovery of unique catalysts. The basis and foundation of this review article is to consider the recently published developments (2014-2019) in the synthesis and catalytic applications of copper supported by silica nanocomposites, carbon nanocomposites, and magnetic nanocomposites for expanding the "click" chemistry.

An overview on recent advances in the synthesis of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials and their catalytic applications in chemical processes.

This review article discusses the progress related to the synthesis and catalytic applications of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials for industrial and laboratory products. These catalysts are widely used in acid-catalyzed processes. Most of these acid catalysts are eco-friendly, reusable, and stable. Moreover, the discovery of unique catalysts is vital for developing new, efficient, and reusable catalysts for industrial and laboratory applications. The aim of this review article is to review the recent studies (2014-2018) in the field of the utility of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials for developing acidic catalysts.

Solvent-free and room temperature synthesis of 3-arylquinolines from different anilines and styrene oxide in the presence of Al2O3/MeSO3H.

A highly efficient, simple and environmentally friendly synthesis of 3-arylquinolines has been developed in the presence of Al2O3/MeSO3H via one-pot reaction of anilines and styrene oxide. This methodology provides very rapid access to 3-arylquinolines in good to excellent yields under solvent-free conditions at room temperature in air.

Crystal structure of {(E)-4-[(1-allyl-1H-1,2,3-triazol-4-yl)meth-oxy]benzyl-idene}[2-(morpholin-4-yl)eth-yl]amine.

In the title compound, C19H25N5O2, the morpholine ring has a chair conformation. The plane of the central benzene ring makes dihedral angles of 88.75 (12) and 60.02 (7)°, respectively, with the mean plane formed by the four planar C atoms of the morpholine ring and with the plane of the triazole ring. In the crystal, mol-ecules are linked via C-H⋯π inter-actions, forming slabs lying parallel to (10-1). The C atoms of the bridging ethyl-ene group, between the morpholine and benzene rings, and the terminal ethene group of the prop-1-ene substituent attached to the triazole ring, are disordered over two sets of sites, with an occupancy ratio of 0.634 (13):0.366 (13).

An efficient catalytic system based on 7,8-dihydroxy-4-methylcoumarin and copper(II) for the click synthesis of diverse 1,4-disubstituted-1,2,3-triazoles under green conditions.

In this work, the combination of 7,8-dihydroxy-4-methyl coumarin (DHMC) as a novel bidentate O,O-chelating agent and copper(II) acetate monohydrate (2:1 molar ratio) has been found to form an efficient catalytic system. This catalyst provided good to excellent yields in the multi-component click synthesis of 1,4-disubstituted-1,2,3-triazoles by using various structurally diverse organic halides, different non-activated terminal alkynes, and sodium azide. This catalytic system eliminates the need for the isolation of the hazardous azide intermediates which are generated in situ. The reaction is carried out in aqueous phase at room temperature and it can be accelerated by sonication or by increasing the reaction temperature. Moreover, the reaction can be performed in large scale. It is noteworthy that DHMC is commercially available and that it can be easily synthesized with low cost materials.

(E)-Benz-yl(4-{[1-(prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}benzyl-idene)amine.

The triazole ring of the title compound, C20H20N4O, is normal to the central benzene ring, making a dihedral angle of 90.0 (3)°, and forms a dihedral angle of 69.2 (3)° with the terminal phenyl ring. The dihedral angle between the phenyl and benzene rings is 88.2 (3)°. The atoms of the terminal propenyl group are disordered over two sets of sites, with a site-occupancy ratio of 0.663 (13):0.337 (13). In the crystal, C-H⋯N contacts lead to the formation of a layer structure extending parallel to (011). Two weak C-H⋯π inter-actions are also observed.

(E)-N-(4-{[1-(Prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}benzyl-idene)morpholin-4-amine.

The asymmetric unit of the title compound, C17H21N5O2, contains two crystallographically independent mol-ecules, which are linked by a C-H⋯N hydrogen bond. The morpholine rings of both mol-ecules adopt distorted chair conformations. The dihedral angles between the triazole and benzene rings are 12.8 (3)° in the first independent molecule in which the -N=C- group between the morpholine and benzene rings is disordered [site-occupancy ratio = 0.576 (7):0.424 (7)] and 88.1 (2)° in the second independent mol-ecule. In the crystal, mol-ecules are linked by C-H⋯N hydrogen bonds along the [100] direction. In addition, one weak C-H⋯π inter-action and two weak π-π stacking inter-actions [centroid-centroid distances = 3.840 (3) and 3.823 (2) Å] between the triazole rings of adjacent mol-ecules are observed. The atoms of the terminal propenyl groups in both mol-ecules are disordered over two sets of sites [site-occupancy ratios = 0.691 (10):0.309 (10) and 0.705 (15):0.295 (15)].

(E)-N-(1,3-Benzodioxol-5-yl)-1-(4-{[1-(prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}phen-yl)methanimine.

In the title compound, C20H18N4O3, the dihedral angles between the central benzene ring and the 1H-1,2,3-triazole ring and the fused benzene ring are 65.34 (19) and 3.64 (18)°, respectively. The dioxole ring adopts a shallow envelope conformation, with the methyl-ene C atom displaced by 0.156 (5) Šfrom the other four atoms (r.m.s. deviation = 0.007Å). In the crystal, the mol-ecules are linked by C-H⋯O and C-H⋯N hydrogen bonds, generating a three-dimensional network.

4-(1-Methyl-eth-yl)-N-((E)-4-{[1-(prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}benzyl-idene)aniline.

In the title compound, C(22)H(24)N(4)O, the terminal and central benzene rings make dihedral angles of 52.7 (3) and 43.8 (2)°, respectively, with the triazole ring. The dihedral angle between the benzene rings is 8.9 (2)°. The crystal structure features C-H⋯π inter-actions. The atoms of the terminal propenyl group are disordered over two sets of sites, with a refined occupancy ratio of 0.714 (14):0.286 (14).

3,4-Dimeth-oxy-N-((E)-4-{[1-(prop-2-en-1-yl)-1H-1,2,3-triazol-4-yl]meth-oxy}benzyl-idene)aniline.

In the title compound, C(21)H(22)N(4)O(3), the triazole ring is planar [maximum deviaton = 0.004 (1) Å] and makes dihedral angles of 26.21 (8) and 38.66 (8)° with the two benzene rings. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming zigzag chains along [1-11]. In addition, a weak C-H⋯π intreraction is also observed.