Arylidene Derivatives Research Articles

Tunable full-color dual-state (solution and solid) emission of push-pull molecules containing the 1-pyrindane moiety.

A facile method for the synthesis of arylidene derivatives of pyrindane - (E)-7-arylmethylene-2-chloro-6,7-dihydro-5H-cyclopenta[b]pyridine-3,4-dicarbonitriles - was developed. Tunable full-color emission was achieved for the synthesized push-pull molecules, solely by changing donor groups while keeping both the conjugated system and acceptor part of the molecule unchanged. This represents a rare approach for the design of such fluorophores. Arylidene derivatives of pyrindane were found to be efficient fluorescent dyes showing a moderate to high emission quantum yield. The push-pull molecules were also characterized by a dual-state emission (in solution and in the solid state). Emission maxima ranged from 469 to 721 nm in solution depending on the solvent and type of donor substituent, and from 493 to 767 nm in the solid state. For the arylidene derivative of pyrindane with a dimethylamino group, it was shown that fluorescence can be changed by the action of an acid both in solution and in the solid state.

Synthesis and antioxidant properties of novel hybrid molecules containing gallic acid and thiazolidinone moieties

Thiazolidinones, are characterized by a thiazolidine ring structure, have highly biological applications. So, novel hybrid thiazolidinone moieties containing gallic acid were synthesized via cyclo-condensation process or standard Knoevenagel reactions. Hydrazineyl-thiazol-4(5H)-one 2 derivative was synthesized to condensed with benzaldehydes to afford benzylidene thiazolidinone derivatives 3a-c. Also, the product 2 reacted with benzyl bromide or nitro benzyl bromide to give their corresponding methylene active derivatives 4a,b which were readily reacted with aromatic aldehydes to produce 5-arylidene derivatives 5a-f via Knoevenagel reactions. The new thiazolidine derivatives were elucidated according to their spectroscopic and elemental analyses. Two thiazolidinone derivatives 4a,b were elucidated via X-ray analysis. Also, antioxidant activity of the new products were run by DPPH assay and in comparison with reference antioxidants (ascorbic acid and BHT). The results revealed that eight compounds was higher than BHT and was increasing in the following order 4a < 5f < 5a< 3c < 5b < 5d < 3a< 5c. The antioxidant activity of ascorbic acid was higher than all compounds in which compound 5c was very close in its activity with the ascorbic acid.

TCS/ZnCl2 as a controlled reagent for the Michael addition and heterocyclic cyclization based on the phenyl pyrazolone scaffold with docking validation as a Covid-19 protease inhibitor

TCS/ZnCl2 is presented as a new catalyst for achieving the Michael addition adduct 5a-g by the reaction of phenyl pyrazolone 4 as the Michael donor and arylidene derivatives 3a-g as the Michael acceptor. The one-pot multi-component reaction of the same fragments' scaffolds as aldehydes 1a-g, malononitrile (2), and phenyl pyrazolone 4 with the same catalyst gives pyrano[2,3-c]pyrazole derivatives 6a-g as final products. The prepared compounds undergo docking validation as COVID-19 protease inhibitors and are compared with hydroxychloroquine as a reference drug. KEY WORDS: Pyranopyrazole, multi-component reactions, TCS/ZnCl2 catalyst, COVID-19, the energy score, hydroxychloroquine Bull. Chem. Soc. Ethiop. 2024, 38(4), 1119-1127. DOI: https://dx.doi.org/10.4314/bcse.v38i4.24

Synthesis and antibacterial activities of novel hybrid molecules based on benzothiazole, benzimidazole, benzoxazole, and pyrimidine derivatives, each connected to N-arylacetamide and benzoate groups

Novel benzimidazoles, benzothiazoles, and benzoxazoles linked to N-arylacetamide were synthesized in good yields by reacting a series of 2-oxo-2-(arylamino)ethyl 4-formylbenzoates with o-phenylenediamine, 2-aminothiophenol, or 2-aminophenol in ethanol at reflux in the presence of NaHSO3. Attempts to use the new aldehydes as adaptable precursors for the synthesis of fused dihydropyran or fused dihydropyridine via Michael or Hantzsch's reactions were unsuccessful; instead, the processes produced the corresponding arylidene derivatives. The structures of the novel compounds were verified with a variety of spectra. All synthesized compounds were evaluated for antibacterial activity against four different bacterial strains. Compound 6a had good activity against Escherichia coli in an agar diffusion assay, with an inhibitory zone width of 30 mm compared to ofloxacin (20 mm). Compounds 18a and 18b were most effective against Bacillus subtilis, with MICs of 156.3 and 312.5 µg/mL, respectively. Molecular docking investigations demonstrated that compounds 6a, 18a, and 18b had high binding affinities for bacterial tyrosyl-tRNA synthetase and DNA gyrase.

Discovery of thiazolidinedione-based pancreatic lipase inhibitors as anti-obesity agents: synthesis, in silico studies and pharmacological investigations

A series of new 2,5-disubstituted arylidene derivatives of thiazolidinedione (16a-e, 17a-d, 18a-c) designed using molecular hybridization approach were synthesized, structurally characterized, and explored for their anti-obesity potential via inhibition of Pancreatic Lipase (PL). Compound 18a presented the most potent PL inhibitory activity with IC50 = 2.71 ± 0.31 µM, as compared to the standard drug, Orlistat (IC50 = 0.99 µM). Kinetic study revealed reversible competitive mode of enzyme inhibition by compound 18a with an inhibitory constant value of 1.19 µM. The most promising compound 18a revealed satisfactory binding mode within the active site of the target protein (human PL, PDB ID: 1LPB). Also, MM/PBSA binding free energy and molecular dynamics (MD) simulation analysis were performed for the most promising compound 18a, which showed potent inhibition according to the results of in vitro studies. Furthermore, a stable conformation of the 1LPB-ligand suggested the stability of this compound in the dynamic environment. The ADME and toxicity analysis of the compounds were examined using web-based online platforms. Results of in vivo studies confirmed the anti-obesity efficacy of compound 18a, wherein oral treatment with compound 18a (30 mg/kg) resulted in a significant reduction in the body weight, BMI, Lee index, feed intake (in Kcal), body fat depots and serum triglycerides. Compound 18a significantly decreased the levels of serum total cholesterol (TC) to 128.6 ± 0.59 mg/dl and serum total triglycerides (TG) to 95.73 ± 0.67 mg/dl as compared to the HFD control group. The present study identified disubstituted TZD derivatives as a new promising class of anti-obesity agents. Communicated by Ramaswamy H. Sarma

Synthesis of new 2‐pyridinone and thiazole derivatives containing coumarin moiety

AbstractCoumarin has shown considerable therapeutic potency because of its versatile biological prosperities. Also, pyridines have been adopted in medicinal chemistry as potent ring. Moreover, several investigations reported the potency of thiazole‐containing compounds. So, during this research, new functionalized 2‐pyridinone and thiazole derivatives bearing coumarin moiety were aimed to synthesize. Many trials to obtain the 6‐amino‐2‐oxo‐pyridine‐3,5‐dicarbonitriles through the condensation of cyanoacetohydrazone of 3‐acetyl coumarin with 2‐(arylidene)malononitriles were carried out using different reaction conditions. In all cases, the reaction gave none of the corresponding 2‐pyridinone derivatives except the reaction with 2‐(benzylidene)‐malononitrile afforded product in few yield. Moreover, the reaction of another cyanoacetanilide with the 2‐(arylidene)‐malononitrile afforded the unexpected arylidene derivatives rather than the expected pyridin‐2‐one derivatives. Finally, new thiazoles bearing coumarin moiety were synthesized using 3‐acetylcoumarin N‐(2,4‐dimethoxyphenyl)‐thiosemicarbazone. Cyclization of thiosemicarbazone derivative with ethyl 2‐chloroacetate, chloroacetone or phenacyl bromide afforded in high yields the corresponding derivatives of thiazolidin‐4‐one, 4‐methylthiazole or 4‐phenylthiazole, respectively.

Synthesis and antitumor activity of 1,3,4-oxadiazole substituted 2-(5-ylidene-2,4-dioxothiazolidin-3-yl)-acetamides

A series of novel 1,3,4-oxadiazole substituted 2-(5-aryl/heterylidene-2,4-dioxothiazolidine-3-ylidene)-acetamides and their 5-unsubstituted analogues have been synthesized following N-alkylation reaction of 2-chloro-N-(5-aryl-[1,3,4]oxadiazol-2-yl)-acetamides with thiazolidinedione and potassium salts of its arylidene derivatives. The structures of target compounds were confirmed by using 1H NMR spectroscopy and elemental analysis. Evaluation of anticancer activity in vitro for the synthesized compounds was performed in accordance with the National Cancer Institute protocol. A selective influence of some tested compounds against leukaemia MOLT-4 (3e, GP = 76.85%) and K-562 (3e, GP = 79.84%), colon cancer HCT-15 (3d, GP = 76.86%), renal cancer A498 (4a, GP = 74.37%), CAKI-1 (3d, GP = 68.49%) and UO-31 (3b-e, 4a-b, GP = 66.67 ÷ 86.30%) cell lines was established. Grafical abstract:

The design, synthesis, biological evaluation, and molecular docking of new 5-aminosalicylamide-4-thiazolinone hybrids as anticancer agents.

New 5-aminosalicylamide-4-thiazolinone hybrids (27) were efficiently synthesized, characterized, and evaluated to explore their structure-activity relationship as anticancer agents. The antiproliferative activities of the new hybrids were evaluated against eight cancer cell lines using the sulforhodamine B assay. The most potent compound (24b) possessed high selectivity on the tested cell lines in the low micromolar range, with much lower effects on normal fibroblast cells (IC50 > 50 µM). The cell lines derived from leukemia (Jurkat), cervix (HeLa), and colon (HCT116) cancers appeared to be the most sensitive, with IC50 of 2 µM. 24b is the N-ethylamide derivative with p-dimethylaminobenzylidene at position 5 of the 4-thiazolinone moiety. Other N-substituents or arylidene derivatives showed lower activity. Hybrids with salicylamides showed lower activity than with methyl salicylate. The results clearly show that the modifications of the carboxy group and arylidene moiety greatly affect the activity. Investigating the possible molecular mechanisms of these hybrids revealed that they act through cell-cycle arrest and induction of apoptosis and epidermal growth factor receptor (EGFR) inhibition. Molecular docking studies rationalize the molecular interactions of 24b with EGFR. This work expands our knowledge of the structural requirements to improve the anticancer activity of 5-aminosalicylic-thiazolinone hybrids and pave the way toward multitarget anticancer salicylates.

Architecture of the rings of 5-arylidenerhodanine derivatives versus P-gp inhibition.

5-Arylidene derivatives of rhodanine show various biological activities. The new crystal structures of five derivatives investigated towards ABCB1 efflux pump modulation are reported, namely, 2-[5-([1,1'-biphenyl]-4-ylmethylidene]-4-oxo-2-thioxothiazolidin-3-yl)acetic acid dimethyl sulfoxide monosolvate, C18H13NO3S2·C2H6OS (1), 4-[5-([1,1'-biphenyl]-4-ylmethylidene]-4-oxo-2-thioxothiazolidin-3-yl)butanoic acid, C20H17NO3S2 (2), 5-[4-(benzyloxy)benzylidene]-2-thioxothiazolidin-4-one, C17H13NO2S2 (3), 4-{5-[4-(benzyloxy)benzylidene]-4-oxo-2-thioxothiazolidin-3-yl}butanoic acid, C21H19NO4S2 (4), and 5-[4-(diphenylamino)benzylidene]-2-thioxothiazolidin-4-one, C22H16N2OS2 (5). Compounds 1 and 3-5 crystallize in the triclinic space group P-1, while 2 crystallizes in the monoclinic space group P21/n, where the biphenyl moiety is observed in two positions (A and B). Two molecules are present in the asymmetric unit of 5 and, for the other four compounds, there is only one molecule; moreover, 1 crystallizes with one dimethyl sulfoxide molecule. The packing of the molecules containing a carboxyl group (1, 2 and 4) is determined by O-H...O hydrogen bonds, while in the other two compounds (3 and 5), the packing is determined by N-H...O hydrogen bonds. Additionally, induced-fit docking studies have been performed for the active compounds to investigate their putative binding mode inside the human glycoprotein P (P-gp) binding pocket.

Synthesis, in vitro cytotoxic activity and molecular docking study of androstene and estrone derivatives

The development and discovery of steroidal drugs to cure cervical cancer is of the most important. The Claisen condensation of androstene and estrone with aromatic aldehydes was catalyzed by potassium tert. butoxide in tert. butanol to give the corresponding 2-arylidene and 16-arylidene estrone. Subsequently, the 16-arylidene estrone reacted with acid chloride in presence of quaternary amine in halogenated solvent resulting in the steroidal arylidene derivatives. Synthesis, Characterization and in vitro cytotoxic activity of arylidenes are rationalized. Fifteen compounds are synthesized and six of them were evaluated for cytotoxic activity against cervical cancer cell line. HT-3 cell line examination revealed a considerable growth inhibition. Compounds 4a, 4b, 6b, 8c, and 8d, which are estrone-based arylidenes, are the most potent of the series, with IC50 value of 7.15, 10.76, 6.37, 3.56, and 1.55 µM/ml against HT-3 cell line. In addition, molecular docking studies were performed for the steroidal arylidenes to elucidate the binding interactions. Compound 4a, 4b, 6b, 8c and 8d showed excellent binding energy. Docking studies agreed well with in vitro studies. The end result offers an alternative approach to develop steroidal arylidenes that are more effective and are based on estrone, leading to the development of novel anticancer agents.

Dihydrotestosterone-based A-ring-fused pyridines: Microwave-assisted synthesis and biological evaluation in prostate cancer cells compared to structurally related quinolines

Dysfunction of the androgen receptor (AR) signalling axis plays a pivotal role in the development and progression of prostate cancer (PCa). Steroidal and non-steroidal AR antagonists can significantly improve the survival of PCa patients by blocking the action of the endogenous ligand through binding to the hormone receptor and preventing its activation. Herein, we report two synthetic strategies, each utilizing the advantages of microwave irradiation, to modify the A-ring of natural androgen 5α-dihydrotestosterone (DHT) with pyridine scaffolds. Treatment of DHT with appropriate Mannich salts led to 1,5-diketones, which were then converted with hydroxylamine to A-ring-fused 6′-substituted pyridines. To extend the compound library with 4′,6′-disubstituted analogues, 2-arylidene derivatives of DHT were subjected to ring closure reactions according to the Kröhnke’s pyridine synthesis. The crystal structure of a monosubstituted pyridine product was determined by single crystal X-ray diffraction. AR transcriptional activity in a reporter cell line was investigated for all novel A-ring-fused pyridines and a number of previously synthesized DHT-based quinolines were included to the biological study to obtain information about the structure-activity relationship. It was shown that several A-ring-fused quinolines acted as AR antagonists, in comparison with the dual or agonist character of the majority of A-ring-fused pyridines. Derivative 1d (A-ring-fused 6′-methoxyquinoline) was studied in detail and showed to be a low-micromolar AR antagonist (IC50 = 10.5 µM), and it suppressed the viability and proliferation of AR-positive PCa cell lines. Moreover, the candidate compound blocked the AR downstream signalling, induced moderate cell-cycle arrest and showed to bind recombinant AR and to target AR in cells. The binding mode and crucial interactions were described using molecular modelling.

Design, synthesis and antimicrobial evaluation of benzimidazole containing 4-thiazolidinone based 5-arylidene derivatives

In an attempt to design a potent class of antimicrobials, we have synthesized benzimidazole derivatives based on 4-thiazolidinone which possessed 5-arylidenes 5a-o by using different catalysts under multistep conventional synthesis. Structures of the synthesized compounds have been established based on spectral data and compounds have been screened for their antimicrobial activity. Compound 5j shows maximum potency against all Gram-positive bacteria with a minimum inhibitory concentration (MIC) in the range of 25-50&nbsp;μg/mL while moderate activity against Gram-negative bacterial strains is observed with a MIC value of 62.50&nbsp;μg/mL. Compound 5n is found to be the most active against fungal strains with a MIC value of 250&nbsp;μg/mL.

Reaction of 2-R-naphtho[2,3-d][1,3,2]dioxaphosphinin-4-ones with arylidene derivatives of malonic acid esters: synthesis, molecular and crystal structures of 5-oxo-2-R-naphtho[2,3-f][1,2]oxaphosphepine 2-oxides

Reaction of 2-R-naphtho[2,3-d][1,3,2]dioxaphosphinin-4-ones with arylidene derivatives of malonic acid esters: synthesis, molecular and crystal structures of 5-oxo-2-R-naphtho[2,3-f][1,2]oxaphosphepine 2-oxides

A-ring-fused pyrazoles of dihydrotestosterone targeting prostate cancer cells via the downregulation of the androgen receptor

High expression of the androgen receptor (AR) and the disruption of its regulation are strongly responsible for the development of prostate cancer (PCa). Therapeutically relevant non-steroidal or steroidal antiandrogens are able to block the AR effect by eliminating AR-mediated signalling. Herein we report the synthesis of novel steroidal pyrazoles derived from the natural sex hormone 5α-dihydrotestosterone (DHT). 2-Ethylidene or 2-(hetero)arylidene derivatives of DHT obtained by regioselective Claisen-Schmidt condensation with acetaldehyde or (hetero)aromatic aldehydes in alkaline ethanol were reacted with monosubstituted hydrazines to give A-ring-fused 1,5-disubstituted pyrazoles as main or exclusive products, depending on the reaction conditions applied. Spontaneous or 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ)-induced oxidation of the primarily formed pyrazolines resulted in the desired products in moderate to good yields, while 17-oxidation also occurred by using the Jones reagent as a strong oxidant. Transcriptional activity of the AR in a reporter cell line was examined for all novel compounds, and several previously synthesized similar DHT-based pyrazoles with differently substituted heteroring were also included to obtain information about the structure-activity relationship. Two specific regioisomeric groups of derivatives significantly diminished the transcriptional activity of the AR in reporter cell line in 10 μM concentration, and displayed reasonable antiproliferative activity in AR-positive PCa cell lines. Lead compound (3d) was found to be a potent AR antagonist (IC50 = 1.18 μM), it generally suppressed AR signalling in time and dose dependent manner, moreover, it also led to a sharp decrease in wt-AR protein level probably caused by proteasomal degradation. We confirmed the antiproliferative activity of 3d in AR-positive PCa cell lines (with GI50 in low micromolar ranges), and its cellular, biochemical and in silico binding in AR ligand-binding domain. Moreover, compound 3d was shown to be potent even ex vivo in patient-derived tissues, which highlights the therapeutic potential of A-ring-fused pyrazoles.

Design, synthesis, molecular modelling and antitumor evaluation of S-glucosylated rhodanines through topo II inhibition and DNA intercalation

In the present study, 5-arylidene rhodanine derivatives 3a–f, N-glucosylation rhodanine 6, S-glucosylation rhodanine 7, N-glucoside rhodanine 8 and S-glucosylation 5-arylidene rhodanines 13a–c were synthesised and screened for cytotoxicity against a panel of cancer cells with investigating the effective molecular target and mechanistic cell death. The anomers were separated by flash column chromatography and their configurations were assigned by NMR spectroscopy. The stable structures of the compounds under study were modelled on a molecular level, and DFT calculations were carried out at the B3LYP/6-31 + G (d,p) level to examine their electronic and geometric features. A good correlation between the quantum chemical descriptors and experimental observations was found. Interestingly, compound 6 induced potent cytotoxicity against MCF-7, HepG2 and A549 cells, with IC50 values of 11.7, 0.21, and 1.7 µM, compared to Dox 7.67, 8.28, and 6.62 µM, respectively. For the molecular target, compound 6 exhibited topoisomerase II inhibition and DNA intercalation with IC50 values of 6.9 and 19.6 µM, respectively compared to Dox (IC50 = 9.65 and 31.27 µM). Additionally, compound 6 treatmnet significantly activated apoptotic cell death in HepG2 cells by 80.7-fold, it induced total apoptosis by 34.73% (23.07% for early apoptosis, 11.66% for late apoptosis) compared to the untreated control group (0.43%) arresting the cell population at the S-phase by 49.6% compared to control 39.15%. Finally, compound 6 upregulated the apoptosis-related genes, while it inhibted the Bcl-2 expression. Hence, glucosylated rhodanines may serve as a promising drug candidates against cancer with promising topoisomerase II and DNA intercalation.

Ulcer Index, Analgesics and Anti inflammatory Screening of Some Arylidene Compounds Derived from Phenyl Hydrazine and Aromatic Aldehydes

Arylidene derivatives were synthesized from phenyl hydrazine and series of different aldehydes. Arylidene compounds are important classes of N-containing fused heterocycles widely used as key building blocks for pharmaceutical agents due to a wide range of biological activities that include anti-inflammatory and antitumor properties [1]. Arylidene derivatives were furnished by the fusion of benzene ring with different aldehydes via hydrazine moiety in the presence of glacial acetic acid. These derivatives were characterized by TLC, melting points, Infrared Red, Nuclear Magnetic Resonance and Mass Spectroscopy. Finally, these synthetized derivatives were tested for analgesic activity using hot plate test method, anti-inflammatory activity using rat paw oedema and ulcer index test.

SYNTHESIS AND CONVERSION OF NEW POTENTIALLY BIOLOGICALLY ACTIVE 4-THIAZOLIDINONE DERIVATIVES WITH A TRIAZINOINDOLE FRAGMENT IN THE MOLECULES

A wide spectrum of biological activity and the possibility of diverse chemical modification of isatinderivatives prompts the search for new highly active compounds as potential drugs among condensed and noncondensedheterocyclic systems containing the specified molecular "matrix". Studies of 1,2,4-triazino[5,6-b]indoles,the chemical precursors of which are isatins, have shown the prospect of their use in the treatment of oncologicaldiseases. In addition, potential antifungal, antiviral, antihypertensive agents have been identified among thesederivatives.Adhering to the main synthetic strategy of our research, which is based on the "hybrid-pharmacophoric" approach inthe synthesis of new heterocyclic derivatives of 4-thiazolidinone, in our opinion, the combination of the mainscaffold (4-thiazolidinone) and the structural "imitator" is interesting and promising of the isatin "matrix" -triazinoindole fragment, as well as the synthesis of new polyheterocyclic ensembles, including those with apharmacologically attractive pyrazoline fragment. Under the conditions of the S-alkylation reaction of 3-mercapto-5H-1,2,4-triazino[5,6-b]indoles, 2-chloro-1-(3,5-diaryl-4,5-dihydropyrazole- 1-yl)ethanones, which made it possibleto obtain 1,2,4-triazino[5,6-b]indole-pyrazolines with preparative yields. By hydrazinolysis of 3-mercapto-5H-1,2,4-triazino[5,6-b]indoles, corresponding hydrazines were obtained, which were successfully used for the first time inthe Holmberg reaction, and derivatives of the triazinoindole-thiazolidinone system were obtained – 3-(1,2 ,4-triazino[5,6-b]indol-3-ylamino-2-thioxothiazolidin-4-ones Chemical modification of methylene-active compoundswas carried out under the conditions of the Kniovenagel reaction with aromatic aldehydes and isatin derivatives,which was substantiated by the results of biological studies of structurally related heteryl-substituted 5-ylidenerhodanines. The synthesis of derivatives of the 4-thiazolidinone-thiadiazinoindole system, which is based onthe interaction of N-(1,3,4-thiadiazinoindol-2-yl)-2-chloroacetamides with ammonium thiocyanate in an acetonemedium, was carried out. The obtained conjugates are methylene-active compounds, which made it possible tosynthesize a series of 5-arylidene derivatives under the conditions of the Kniovenagel reaction. The purpose of thework is to experimentally confirm or refute the feasibility of chemical modification of isatin into the triazineindolinesystem and its combination with 4-thiazolidinone biophore for the search of new biologically activecompounds, including highly active antitumor agents. The structure of the synthesized compounds was confirmedby NMR spectroscopy. To study the structure in the solid state, the IR spectra of the key compounds in KBr tabletswere studied.

Design, Synthesis, Antimicrobial Activity and Molecular docking Studies of Pyridine Based Thiazolidine-4-one and Its 5-Arylidene Derivatives

This study analysed the interactions between the chemical structures and antimicrobial activities of various functional groups containing organic compounds. The spectral methods confirmed the structure of these compounds after efficient synthesis was carried out. Two Gram-positive and two Gram-negative bacteria were tested for in vitro antibacterial activity of the synthesised compounds. For antifungal activity, three fungal strains were tested. Compound 5n showed a potent inhibitory effects against E. coli and P. aeruginosa with MIC values of 12.5 µg/ml and 6.25 µg/ml, respectively (Glide Docking score: -9.190). S. aureus and S. pyogenus were both positively affected by compound 5i with MIC values of 12.5 µg/ml and 25 µg/ml, respectively (Glide Docking score: -9.111). Based on the results, compounds 5a and 5f have excellent activity against C. albicans with MIC values of 200 µg/ml. Molecular docking study against microbial peptide deformylase could provide insight into the binding affinity and orientation of the active site. A very significant correlation was obtained between the in silico binding affinity data with an average Glide docking score of -8.412 and Glide binding energy: -43.074 kcal/mol. Compound 5n produced a relatively higher binding affinity (Glide dock score: -9.190 and Glide binding energy: -51.226 kcal/mol) which was also translated in its higher antimicrobial activity.

Condensation Reactions of Aromatic Aldehydes with Active Methylene Compounds: The Beneficial Sinergy of Alkaline Ionic Liquid in One Pot Synthesis

Background: In recent times, there has been on-going interest in developing convenient and environmentally friendly synthetic methods in organic chemistry. The use of ionic liquid catalysts in organic synthesis is a developing area that allows reactions to be run at low temperatures and without solvents. Literature overview revealed that room temperature supported ionic liquid catalysis is a developing field in catalytic science with huge application in organic synthesis. Hence in this current article, our focus is on the one-pot synthesis of arylidene derivatives with the use of ([bmim] OH) ionic liquid. Objectives: We describe here the use of an ionic liquid catalyst, 1-n-butyl-3-methylimidazolium hydroxide, [bmim] OH), in the convenient one pot synthesis of arylidene derivatives by the reaction of the active methylene compound, malononitrile, with pyrazole aromatic aldehydes under microwave irradiation. Methods: The functionalized ionic liquid, 1-n-butyl-3-methylimidazolium hydroxide ([bmim] OH), catalyzed Knoevenagel condensation reactions of pyrazole aromatic aldehydes with active methylene compound malononitrile carried out under microwave irradiation. The reaction progress was monitored by thin layer chromatography and the synthesized compounds were further characterized by NMR spectroscopy. Results: This proposed work demonstrates the utility of the use of the ionic liquid catalyst [bmim] OH, in the suitable, high yield (80-95%) microwave assisted reactions of pyrazole aromatic aldehydes with the active methylene compound, malononitrile. Conclusion: An eco-friendly synthesis of pyrazole derivatives has been demonstrated using ([bmim] OH) ionic liquid as a catalyst for the Knoevenagel condensation reactions of pyrazole aromatic aldehydes and malononitrile with microwave irradiation. The advantages of this green method are its convenience, mild reaction conditions, and high product yields (80-95%).

Design, Synthesis, and Spectroscopic Studies of Some New α-Aminophosphonate Analogues Derived from 4-Hydroxybenzaldehyde with Special Reference to Anticancer Activity.

IntroductionAs biological activity components, α-aminophosphonates and their moieties play important roles in medicinal chemistry. Alpha-phosphonic acids are significant α-amino acid counterparts. Due to its strong biological activity, this class of molecule has recently been discovered to have numerous medical applications.Results and DiscussionA new class of α-aminophosphonates and arylidene derivatives was synthesized. Various spectroscopic and elemental analyses were used to confirm the prepared products. The produced materials were tested as anticancer against breast carcinoma cells and normal human cells (PBMC). Besides the analysis results, it was found that (7b, 4c, 5k, 6, 5a, 7c, 5f, 5b, and 5g) against MCF-7 line cells. As a reference anticancer drug, 5-fluorouracil was used. The anticancer activities showed that the compounds 7b, 4c, containing α-aminophosphonate and Schiff base groups, respectively, showed high inhibition activity against the MCF-7 cell line, with 94.32% and 92.45% inhibition compared to the inhibition by 5-FU with 96.02% inhibition. The results showed that the compounds 5k, 7b, 6, and 5a, respectively, had very low activity against normal human cells PBMC, with 12.77%, 13%, 13.13%, and 17.88% inhibition compared to the inhibition by 5-FU with 12.50% inhibition. The binding energy for non-bonding interactions between the ligand (studied compounds) and receptor, thymidylate synthase, was determined using molecular docking (pdb code: 1AN5).Conclusionα-aminophosphonate derivatives, arylidines, and disphosphonate derivatives derived from 4-hydroxybenzaldehyde were synthesized, purified, elucidated by spectroscopic analysis, and finally tested against carcinoma breast cancer to give high to moderate to low activity.