Screening of Streptococcus mutans Sortase A Via Myricetin-Like Inhibitors: In Vitro Evaluation and Molecular Docking-Based Virtual

Background: Dental caries is one of the most common causes threatening human health globally. Sortase A (Srt A) as a transpeptidase, mediates the attachment of the Streptococcus mutans cell wall to dental surfaces by biofilm formation. Due to the development of multidrug-resistance bacteria, attempting to discover growth inhibitors is logical and promising. Objectives: The current study aimed at the experimental and docking-based virtual screening of myricetin-like inhibitors for the inhibition of Srt A enzyme in S. mutans isolates. Methods: Sixty-three S. mutans were isolated from pupils based on cultural, morphological, and biochemical characteristics (N = 150). After identifying the srtA gene using the polymerase chain reaction (PCR) with specific primers, a broth microdilution test was conducted according to CLSI-2020 criteria to determine the minimum inhibitory concentration (MIC) of myricetin. The in silico exploration of Srt A inhibitors was performed using AutoDock 4.2.6. Results: The frequency of S. mutans isolates containing the srtA gene was 87.3% of which, fifty isolates (79.4%) were categorized as susceptible to myricetin (MIC ≤ 16 μg/mL). Of 20 ligands having a high degree of similarity with myricetin, the best docking results were related to ligand 2. Conclusion: It was concluded that myricetin has an inhibitory effect on oral bacteria in vitro, and ligand 2 had the most negative binding energy (-4.66 kcal/mol) and favorably interacts with the key amino acid residues at the active site of Srt A. Accordingly, this ligand can be utilized as a lead compound for further studies to discover novel inhibitors targeting Srt A in S. mutans

An efficient method for synthesis of stable phosphorus ylides and 1,4-diionic organophosphorus compounds in the presence of sodium dodecyl sulfate in aqueous media

AbstractStable crystalline phosphorus ylides and 1,4-diionic organophosphorus compounds were obtained in good to excellent yields from the 1:1:1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates and β-dicarbonyl or heterocyclic compounds, such as diethyl malonate, acetyl acetone, 1,3-diphenyl propane-1,3-dione, 1,3-dimethylbarbituric acid, meldrum’s acid, 2-benzoxazolinone, benzotirazole, and 2-thiazoline-2-thiol in the presence of sodium dodecyl sulfate as a surfactant in water. Green synthesis, mild conditions, decreasing timescale of reaction, low cost, and easy workup are the main advantages of this method

Multi-component Reaction Synthesis of 1,6-diamino-2-oxo-1,2,3,4-tetrahydropyridine-3,5-dicarbonitriles Using Ultrasonication and Dmap as Catalyst

4-(Dimethylamino)pyridine was found to be the homogenous and efficient catalyst for one-pot, multi-component reactions between hydrazine monohydrate, ethyl cyanoacetate, ketone, and malononitrile for the synthesis of 1,6-diamino-2-oxo-1,2,3,4-tetrahydropyridine-3,5-dicarbonitrile derivatives using ultrasonication at room temperature in ethanol solution within 35-50 min with yields of over 90%. This procedure offers various remarkable features such as short reaction times, clean reaction condition, excellent yields, and easy work-up methods

Three-component carbon-carbon bond-forming reactions for the synthesis of β-amino carbonyl compounds using maleic acid-catalyzed one-pot mannich-type reaction in ethanol

Herein, we described a one-pot, three-component and environmentally benign method for the synthesis of β-amino ketones based on the reaction of acetophenones, aromatic aldehydes, and aromatic amines using maleic acid as a green catalyst in ethanol as green solvent. The present methodology offers several advantages including good yields, mild reaction conditions and an inexpensive catalyst with a very easy work up. In addition, this method excludes the use of volatile organic solvents, tedious workup and column chromatographic purification of compounds, making the method greener, convenient and superior. All new compounds were well characterized by IR, 1H and 13C NMR spectroscopy and physical data

Salicylic acid as a naturally green Brønsted acid catalyst for eco-friendly and simple synthesis of polysubstituted dihydro-2-oxypyrroles under ambient temperature

An efficient and environmental friendly methodology for the synthesis of polysubstituted dihydro-2-oxypyrroles via a one-pot four-component domino condensation of dialkyl acetylenedicarboxylate, formaldehyde and amines (aromatic and aliphatic) at present of    salicylic acid as an economical and naturally green Brønsted acid catalyst under ambient temperature with excellent yields and short reaction times is described. Green, natural, inexpensive and non-toxic catalyst, easily separated with no column chromatographic separation and highly efficient is an option for the simple synthesis of these rings

An efficient solvent-free synthesis of pyrido[2,3-d]pyrimidine derivatives utilizing lactic acid as green and eco-friendly catalyst

An efficient, solvent-free and one-pot procedure for the synthesis of pyrido[2,3-d]pyrimidine derivatives by condensation of aromatic aldehydes, malononitrile and 6-amino-1,3-dimethyl uracil at 90°C catalyzed by lactic acid as an inexpensive, biological and eco-friendly compound is described. The remarkable benefits of this procedure are green and environmentally friendly reaction conditions, high yields, short reaction time, simple methodology and easy workup

An efficient solvent-free synthesis of pyrido[2,3-d]pyrimidine derivatives utilizing lactic acid as green and eco-friendly catalyst

1368-1372An efficient, solvent-free and one-pot procedure for the synthesis of pyrido[2,3-d]pyrimidine derivatives by condensation of aromatic aldehydes, malononitrile and 6-amino-1,3-dimethyl uracil at 90°C catalyzed by lactic acid as an inexpensive, biological and eco-friendly compound is described. The remarkable benefits of this procedure are green and environmentally friendly reaction conditions, high yields, short reaction time, simple methodology and easy workup

Green Synthesis of Polysubstituted Quinolines and Xanthene Derivatives Promoted by Tartaric Acid as a Naturally Green Catalyst under Solvent-free Conditions

This method reported the use of tartaric acid as a green and highly efficient catalyst for the convenient synthesis of polysubstituted quinolines and xanthenes derivatives in excellent yields under solvent-free conditions. The main advantages of this one-pot procedure are the green and economic availability of the catalyst, simple experimental and work-up procedures

Glycoconjugates via Phosphorus Ylides

A facile, high yielding access to rare chimeric compounds combining phosphorus ylides with complex glycosyl formamides is described. We determined X-ray structures gaining structural insight into this compounds class. In addition, data mining of similar compounds deposited within the Cambridge Structural Database was performed. These derivatives could be used either as synthetic intermediates via the ylide functionalization and glyco chemical biology synthons or improving the pharmacokinetic properties of a potential bioactive molecule, exploiting the glycosyl moiety

Three-component coupling approach for the synthesis of 4H-pyrans and pyran-annulated heterocyclic scaffolds utilizing Ag/TiO2 nano-thin films as robust recoverable catalyst

127-135As a segment of ongoing surveys and with the aim of expansion of environmentally benign processes, a series of biologically varied type of substituted 2-amino-3-cyano-4H-pyrans and pyran-annulated Scaffolds have been synthesized by tandem Knoevenagel-cyclocondensation of aldehydes, malononitrile, and C-H-activated acidic compounds in aqueous ethanol in the presence of Ag/TiO2 nano-thin films as an eco-friendly, recyclable, and, robust catalyst at 60°C. The salient features of this protocol are mild reaction conditions, producing target compounds in high yields, short reaction times, high atom economy, eco-friendly catalyst, easy isolation of products and no column chromatographic separation. Also, it is observed that the catalyst is highly stable during the reaction and several reuse times without observable loss in catalytic performance