Synthesis of 2-amino-3-cyano-4H-chromen-4-ylphosphonates and their anticancer properties

The medicinal panorama of benzimidazoles and their scaffolds as anticancer and antithrombotic agents: A review

Nitrogen-containing heterocyclic scaffolds have become a prospective pharmacophore with therapeutic importance due to their biological similarities with natural and synthetic drugs. Among all nitrogen heterocyclic compounds, benzimidazoles and their derivatives are privileged molecules structurally akin to naturally available nucleotides, enabling them to intercommunicate with numerous biopolymers in biological systems. This reason enlightens modern researchers worldwide to assess their potential significance in the context of synthetic and biological chemistry. Therefore, it is crucial to merge the latest data with the prior documentation to apprehend the ongoing situation of the benzimidazole moiety in various therapeutic zones of research. The current work displays that the benzimidazole center is a versatile nucleus that offers the necessary data of synthetic alterations for pre-existing compounds to provide new scaffolds to resist numerous therapeutic sectors, including those associated with anticancer and antithrombosis. Due to the potential significance of benzimidazoles, this review aims to emphasize the latest innovations in synthesizing several other notable benzimidazole substrates and their significant pharmacological prospects for the future, including anticancer and antithrombosis.

Synthesis and biological evaluation of novel dialkyl (4-amino-5H-chromeno[2,3-d]pyrimidin-5-yl)phosphonates

This study reports the design and synthesis of novel dialkyl (4-amino-5H-chromeno[2,3-d]pyrimidin-5-yl)phosphonates as potential antitumor agents against A549 (lung cancer), DU-145 (prostate cancer), PC-3 (prostate cancer), HeLa (cervical cancer) and MCF-7 (breast cancer), cell lines evidenced from the in vitro antitumor studies performed by MTT assay (across 10-30 μM concentrations). The structural eminence of these synthesized molecules has emanated by designing the structural core by uniting the chromene, pyrimidine and phosphonate moieties into one, which has augmented their novelty and made them unreported. Further the deep structural activity relationship study investigations articulated that the title compounds are promising drug-like compounds and potential inhibitor of histidine amino acid residue present on the respective enzymatic proteins [3QJZ (A549), 3VHE (DU-145), 3V49 (PC-3), 3F81 (HeLa), & 3R7Q (MCF-7)] of the cell lines screened and are identified as responsible for the multi-faceted antitumor activities predicted in vitro. The obtained results were further supported by molecular docking studies, QSAR, ADMET, and bioactivity studies which have supported them as potential BBB penetrable molecules and proficient CNS active neuro-protective agents during drug delivery.

Heterogeneous catalyst SiO2-LaCl3·7H2O: characterization and microwave-assisted green synthesis of α-aminophosphonates and their antimicrobial activity

Silica-supported lanthanum (III) chloride (SiO₂-LaCl₃·7H₂O) was prepared and characterized by infrared spectroscopy, X-ray diffraction analysis, scanning electron microscope, energy-dispersive X-ray spectroscopy, thermogravimetric analysis and differential thermal analysis techniques. The catalytic activity of this silica-supported lanthanum (III) chloride was investigated in a one-pot three-component Kabachnik-Fields reaction. A library of new α-aminophosphonates was prepared employing various benzothiazole and thiadiazole amines, different substituted aldehydes and diethylphosphite under solvent-free conditions using conventional/microwave methods with good to excellent yields (85-97%). The advantages of this catalyst are that it is environmentally benign, economically inexpensive, and easy to prepare, gives high yields and high purity is less time-consuming, offers easy purification is reusable and enables products to be obtained by simple recrystallization without column chromatography.

PMDTA-catalyzed multicomponent synthesis and biological activity of 2-amino-4H-chromenes containing a phosphonate or phosphine oxide moiety

A new approach for the preparation of (2-amino-3-cyano-4H-chromen-4-yl)phosphonate derivatives is described. The multicomponent reaction of salicylaldehydes, malononitrile and dialkyl phosphites catalyzed by pentamethyldiethylenetriamine (PMDTA) provided the bicyclic derivatives in high yields. The method developed did not require chromatographic separation, since the products could be recovered from the reaction mixture by simple filtration. Our approach made also possible condensation with secondary phosphine oxides, and this reaction has not been previously reported in the literature. The crystal structures of five derivatives were studied by single-crystal XRD analysis. The in vitro cytotoxicity on different cell lines and the antibacterial activity of the (2-amino-4H-chromen-4-yl)phosphonates synthesized were also explored. According to the IC50 values determined, several derivatives showed moderate or promising activity against mouse fibroblast (NIH/3T3) and human promyelocytic leukemia (HL-60) cells. Furthermore, three (2-amino-3-cyano-4H-chromen-4-yl)phosphine oxides were active against selected Gram-positive bacteria.

Synthesis of Biologically Active Molecules through Multicomponent Reactions

Focusing on the literature progress since 2002, the present review explores the highly significant role that multicomponent reactions (MCRs) have played as a very important tool for expedite synthesis of a vast number of organic molecules, but also, highlights the fact that many of such molecules are biologically active or at least have been submitted to any biological screen. The selected papers covered in this review must meet two mandatory requirements: (1) the reported products should be obtained via a multicomponent reaction; (2) the reported products should be biologically actives or at least tested for any biological property. Given the diversity of synthetic approaches utilized in MCRs, the highly diverse nature of the biological activities evaluated for the synthesized compounds, and considering their huge structural variability, much of the reported data are organized into concise schemes and tables to facilitate comparison, and to underscore the key points of this review.

Synthesis and pharmacological properties of polysubstituted 2-amino-4H-pyran-3-carbonitrile derivatives

2-Amino-3-cyano-4H-chromenes are structural core motifs that received increasing attention in the last years due to their interesting potential pharmacological properties. In this review, the synthetic methods for these compounds are classified based on the type of catalyst in the pertinent reactions. In addition, the wide range of pharmacological properties of these compounds is covered in a separate section.

Design and Synthesis of Benzopyranopyrimidinyl Phosphonates as Cytotoxic and Antioxidant Agents

Background:

A concatenation of bioactive diethyl(2-hydroxyphenylsubstituted) benzopyrano pyrimidinyl phosphonates were synthesized under eco-friendly green conditions in the presence of palladium doped graphitic carbon nitride (Pd@g-C3N4) as catalyst.

Methods:

he title compounds were evaluated for cytotoxic activity against MCF-7, SW-480, HeLa and HL-7702 cell lines and in-vitro antioxidant activity by DPPH, NO and H2O2 methods.

Results:

he synthesized compounds manifested robust cytotoxic and antioxidant activities.

Conclusion:

Some of them showed much higher bioactivity than the standards.

Ammonia-Doped Polyaniline-Graphitic Carbon Nitride Nanocomposite as a Heterogeneous Green Catalyst for Synthesis of Indole-Substituted 4H-Chromenes

A nanocomposite of polyaniline with graphitic carbon nitride (GCN) nanosheets has been synthesized by a facile oxidative polymerization of an aniline monomer and GCN to demonstrate its potential to catalyze the synthesis of various indole-substituted 4H-chromenes. The synthesized nanocomposite was thoroughly characterized using different spectroscopic techniques to confirm the morphology and composition. Subsequently, the fabricated nanocomposite was used as a heterogeneous catalyst to synthesize several bioactive indole-substituted 4H-chromenes in an aqueous medium. Organic transformation under benign and environmentally sustainable conditions is of paramount importance in the view of growing environmental pollution. Water is the universal Green solvent and has been a preferred choice of nature to perform various reactions. The catalyst developed in this work showed very good recyclability and adaptability for the synthesis of various medicinally significant indole-substituted 4H-chromenes. This multicomponent reaction imparts very high atom economy (94%) and low environmental factor (0.13).

Synthesis, Crystal Structure and Antitumour Activity of Ethyl 2-[(2-Amino-3-Cyano-4-Phenethyl-4H-Naphtho[1,2-b]Pyran-8-yl)Oxy]acetate

Ethyl 2-[(2-amino-3-cyano-4-phenethyl-4 H-naphtho[1,2- b]pyran-8-yl)oxy]acetate has been synthesised by condensation of ethyl 2-chloroacetate with the hydroxy group of 2-amino-8-hydroxy-4-phenethyl-4 H-naphtho[1,2- b]pyran-3-carbonitrile. The latter was prepared from cinnamaldehyde, malononitrile and naphthalene-1,6-diol through Knoevenagel condensation and cyclisation reaction and then reduction with hydrogen in the presence of Pd/C at room temperature. The crystal structure of the title compound was determined. In addition, the compound showed distinct inhibition of the proliferation of some cancer cell lines.

Catalyst-free ultrasonic-promoted multicomponent synthesis of tertiary α-amino phosphonates

A highly efficient and green protocol has been developed for the synthesis of novel tertiary α-amino phosphonates via a catalyst-free multi-component Kabachnik–Fields reaction under ultrasound irradiation.

Highly efficient green synthesis of α-hydroxyphosphonates using a recyclable choline hydroxide catalyst

Aldehydic carbonyl groups are eco-friendly and efficiently hydrophosphonylated by diethylphosphite using the basic ionic liquid, choline hydroxide.

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

Multicomponent reactions (MCRs) are one of the most important processes for the preparation of highly functionalized organic compounds in modern synthetic chemistry. As shown in this review, they play an important role in organophosphorus chemistry where phosphorus reagents are used as substrates for the synthesis of a wide range of phosphorylated heterocycles. In this article, an overview about multicomponent reactions used for the synthesis of heterocyclic compounds bearing a phosphonate group on the ring is given.

Tungstosulfonic acid as an efficient solid acid catalyst for acylal synthesis for the protection of the aldehydic carbonyl group

Aldehydic carbonyl groups are eco-friendly protected by acetic anhydride using the tungstosulfonic acid catalyst and the deprotection is successful under the similar conditions in the presence of water.

Efficient, Solvent-Free, Multicomponent Method for Organic-Base-Catalyzed Synthesis of β-Phosphonomalonates

An efficient, one-pot, di-n-butylamine-catalyzed, three-component synthesis of β-phosphonomalonates has been developed. A wide range of substrates, including aromatic and fused aromatic aldehydes, were condensed with enolizable C-H activated compounds and dialkylphosphites to give the desired products in excellent yields. This method provides an eco-friendly alternative approach to rapid construction of a diversity-oriented library of β-phosphonomalonates.

One-pot synthesis of 4-alkyl-2-amino-4H-chromene derivatives

A one-pot synthesis of 4-alkyl-2-amino-4H-chromene derivatives by base-initiated reactions of aliphatic aldehydes, malononitrile, and resorcinol in water is described.