Резюме. Our examination planned to synthesize the azido β-lactam under reactive ionic liquids for new synthetic organic methodologies. These endeavors may provide more clarity to the analysis in the systems of natural responses utilizing ionic liquid as response media. The Schiff base witnesses quick responses with azido acidic acid in a [bmim] [PF\(_{6}\)]/[Et\(_{3}\)NH] +[HSO\(_{4}\)] - dissolvable framework, under mellow and unbiased response conditions to afford the corresponding azido β-lactam in high to quantitative yields. The library of substituted 3-azido-4-phenyl1-(-phenylthiazol-2-yl) azetidin-2-one (3a-s) has screened antibacterial movement against clinically secluded Gram-positive bacteria, for example, Staphylococcus aureus, Gram-negative microbes Escherichia coli and Pseudomonas aeruginosa and for antifungal action against Candida albicans strains. Further, the synthesized compound has also assessed by a computational investigation by cooperation with the dynamic site of E150K from MRSA (PDB ID-4BL2). We present the new SwissADME web utensil that gives free access to a pool of quick yet reliable analytical models for physicochemical properties, pharmacokinetics, drug-likeness, and medicinal chemistry. Among them, in-house capable technique, for example, BOILED-Egg, iLOGP, and Bioavailability Radar, are readily available on the web.

Ключови думи: ionic liquid; azido β-lactam; MRSA; SwissADME; BOILED-egg; bioavailability radar

Introduction

In the nineteenth century, azides and azido-related compounds (Rostovtsev et al., 2002) demonstrate the enormous enthusiasm by researchers, the synthesis and reactivity of multifunctional allylic azides become a territory of dynamic research (Cardillo et al., 2005; Feldman et al., 2005; Mangelinckx et al., 2005). In the combination of natural product and nitrogen-containing heterocycles, allylic azides are adaptable building blocks with pharmacological significance (Busetto et al., 1975; Rigby et al., 1979). In specific metal complexes, the coordinated azide responds under generally mellow conditions with electron-poor nitriles (Beck & Fehlhammer, 1967; Fehlhammer et al., 1979), and isonitriles (Pino-Gonzalez et al., 2008) deliver metal-nitrogen, and metal-carbon reinforced tetrazoles, individually. Azide acts as an amino securing cluster (Amantini et al., 2002; Larock, 1989; Scriven & Turnbull, 1988) and is impervious to numerous response conditions; however, it can effectively diminish to amines. The researcher puts a great deal of exertion to portray proficient azido reduction techniques Mitchell et al., 2007; Nyffeler et al., 2002), and some of them connected in carbohydrate functionalization (Busetto et al., 1975; Rigby et al., 1979; Silverman & Dolphin, 1976). In Photoaffinity naming system (Schnapp et al., 1993) the perfluorophenyl azides (Fig. 1) has a vital job and is utilized for the marking of DNA binding proteins (Dezhurov et al., 2005; Lavrik et al., 1996; Lee et al., 2002) are in alteration of human ribosome (Demeshkina et al., 2003a; 2003b), functionalization of bifunctional chelating specialists for γ–imaging, radiotherapy (Lin et al., 2016) and for biotin-labeled photoaffinity tests (Han et al., 2006a; 2006b). The azido nucleosides (Fig. 2) are the genomic building blocks, which interface with nucleic acids, enzymes, and proteins (El Akri et al., 2007), which are significant constituents of living cells.

For the treatment of human immunodeficiency infection (HIV) replication, 3-azido-3-deoxythymidine (AZT) (Fig.3) has primarily been authorized medication, and it also shows short half-life in the body and symptoms (Botta et al., 1998). The (3S,4R)-3-azido-1-(2-hydroxyphenyl)-4-((E)- styryl)azetidin-2-one (Fig.4) show feeble antibacterial movement and great anticancer property (Hakimelahi & Sardarian, 1990), while (3S,4R)-3-azido-1-(2-hydroxyphenyl)-4-((E)-methyl) azetidin-2-one (Fig.5) shows none.

In this context, it is to note that Ajay Bose et al. (1992) prepared azido β–lactam (Fig. 6) from azido acetyl chloride.

In the support Zarei et al. (2011) prepared azido β–lactam (Fig. 7) by efficient conversion of Schiff base by reaction with 2-azidoacetic acid under room temperature.

Reduced thiazole serves in the investigation of polypeptides as a basic unit in compounds of biological imperative, and 2-amino-thiazole has histamine-like action (Ghatole, Lanjewar, & Gaidhane, Syntheses, Characterization, Antimicrobial activity of Copper (II), Zinc (II) and Cobalt (II) Complexes of the bi-dented substituted 2-((E)-2-((2-chloro-6-ethoxyquinolin-3-yl), 2012). We imagined joining a β-lactam ring and different heterocycles in a solitary atom, despite barely any writing reports giving primary, gentle, and efficient routes towards a combination of substituted 3-azido-4-phenyl-1-(- phenylthiazol-2-yl)azetidin-2-one moieties. Generally, a medical clinic tainted by the establishment of a clone of Methicillin-safe Staphylococcus aureus (MRSA), which prompts numerous maladies like skin disease, pneumonia, bacteremia Daum et al., 2002). In some cases, there are mortality and ailment, likewise seen by MRSA contamination, it is a direct result of the obstruction created by the Staphylococcus aureus against treatment (Rossi et al., 2014). The β-lactam antimicrobial like Methicillin, Vancomycin, Teicoplanin, Telavancin, and Ceftaroline utilized for the treatment brought about by the infection of Staphylococcus aureus. The ceftaroline, a recently endorsed medication which restrains penicillin-binding protein (PBP2a) by setting off an allosteric conformational change that prompts the opening of the dynamic site. Presently the second atom of ceftaroline controls the unprotected opened dynamic site. Now the second molecule of ceftaroline inhibits the defenseless opened active site that damages cell-wall, which leads to bacterial death (Fishovitz et al., 2014). In methicillin, Ceftaroline, Penicillin has the β-lactam and thiazole unit in structure. By considering the result of the writing study, we have structured the new molecule of β-lactam with azide functional group to give a productive biomechanical path successfully.

SwissADME is an excellent and exhaustive site kept running by the Swiss foundation of bioinformatics (SIB), which gives bioinformatics administrations and assets to researchers around the world. SIB has more than 65 bioinformatics research gatherings and 800 researchers from the real Swiss schools of advanced education and research institute. SwissADME empowers the appraisal of ADME parameters of medication applicants and small molecules and gives data that permits early hazard evaluation in the drug improvement process. Eminently, swissADME provides a stage to evaluate Lipinski’s rule of five (Lipinski et al., 2001) for medication resemblance of oral bioavailability. Drug-likeness is an unpredictable equalization of molecular properties and structural features that decide if an unfamiliar molecule resembles the known drug. These molecular properties incorporate hydrophobicity, electronic dispersion, and hydrogen bonding attributes molecular size and adaptability. SwissADME includes ‘BOILEDegg’ assessment (Daina & Zoete, 2016) that foresee gastrointestinal captivation (HIA) and efflux/maintenance by P-glycoprotein (Pgp). Also, the blood-brain barrier (BBB) infiltration and Cytochrome P450 (CYP) enzyme substrate-restraint expectation can make.

Besides, there are expanding worries about ecological impacts, which require manufactured control that limit the utilization of hazardous chemicals. Numerous procedures have concocted and examined, particularly by supplanting the customary organic with other non-toxic solvents, for example, water or supercritical carbon dioxide. As of late, ionic liquids have pulled in broad enthusiasm as superb options in contrast to organic solvents, because of their favorable properties, for example, non-combustibility, no quantifiable vapor pressure, low toxicity, reusability, low-cost and high thermal stability (Gordon, 2001l Sheldon, 2001). Notwithstanding the polar properties of ionic liquids, they are non- coordinating, which maintains a strategic distance from any undesired solvent binding in pre-transition states and henceforth offers incredible points of interest for asymmetric synthesis. Subsequently, ionic liquids considered promising elective solvents for organic reactions. In recent years, these liquids have produced a lot of intrigues (Katritzky et al., 2000; Alkiyama et al., 1999l Wenzel & Jacobsen, 2002). In the present examination, the principle preferred standpoint of the utilization of ionic liquids is that these liquid salts can effectively recuperate on workup. Since the items were genuinely dissolvable in the ionic fluids, they could be effectively isolated by straightforward extraction with ether. The staying ionic liquid was utterly washed with ether and reused.

Result and discussion

Chemistry

The impact of solvent for the amalgamation of substituted 3-azido-4-phenyl-1-(4-phenylthizole-2-yl)azetidin-2-one (3a-b) from substituted N-(4-benzylidene)- 4-(4-phenyl)thiazol-2-amine (2a-b) and azido acidic acid under the various condition of time and temperature of refluxed dissolvable organized in Table 1. In the present examination, we have synthesized the azido derivatives of 3a-b in different solvents like DMF, DMSO, CH 3CN, CH2Cl2 under the presence of triethylamine in the other investigation we utilized [bmim][PF 6] and [bmim][PF6]/[Et3NH] +[HSO4] - without triethylamine as a solvent. Bronsted acidic quaternary ammonium sulfate Et 3NH] +[HSO4] - Ghatole et al., 2015) ionic liquid was utilized as an impetus. In the conventional technique, the yield acquired was nearly low and required additional time. Advancement of reaction conditions for all the reactions uncovered that 1–butyl-3-methylimidazoliumhexafluorophosphate i.e. [bmim][PF6] with [Et 3 NH] +[HSO4] - was the suitable solvent. In all reactions, the profitability expanded up to 75-80% with the diminished time factor.

From the above test conditions, it saw that azido derivatives development, promptly happened in the [bmim]PF 6/[Et3NH] +[HSO4] -contrasted with different solvents even nevertheless unadulterated [Et 3 NH] +[HSO4] - and continues in exceptional yields. So, the further synthesis of the 3a-s carried out under [bmim]PF6/[Et3NH] +[HSO4] - with 2 a-s and N 3CH2COOH in 1:1 ratio. The ether soluble ionic liquid was recovered by removing under vacuum and reuse for the synthesis. The recycling efficiency of ionic liquid found decreased after three cycles: the isolated yields and every single physical constant classified in Table 2.

We endeavored the whole arrangement of reactions with fittingly substituted substrates, and the structures affirmed by CHN, IR, 1H NMR, 13C NMR, Mass fragmentation of the compounds. The expected peak in the IR for (2a-s) primary amine

(-NH2) found inside the area 3350-3570 cm-1, the pinnacle comparing to the methoxy group and C-S-C for 2a showed up at 2830-2930 cm-1 and 771cm-1.

The 1H NMR 4-(4-methoxyphenyl) thiazol-2-amine 2a demonstrates a crest as a singlet at δ 3.64 ppm, which corresponds to the amine (-NH2) group. Moreover, the trademark crest for (2a-s) showing up at δ 6.2-7.20 ppm relates to the thiazole ring. However, for the case 2a, C-H of the thiazole ring shows up at δ 6.96 ppm. One-pot transformation of substituted 2a-s to the substituted 3-azido-4-phenyl-1-(4-phenylthizole-2-yl)azetidin-2-ones 3a-s affirmed by the IR spectrum of the compound that indicated groups at 1670-1720cm-1 and 2100-2124cm -1 comparing to the β-lactam carbonyl and azido group respectively.

The IR carbonyl frequencies and the 13C NMR compound movements of the carbonyl carbons rely on the ring size and lie in the normal range. For every other compound with four-membered rings, C=O: 165.0– 168.55, C-N3: 78.01-81.00 showed up. The somewhat extraordinary qualities propose similar stereo structures (barely different conformational circumstances). The 1H NMR range for (3a-s) demonstrated that the doublet for C7 and C8 hydrogen of the β-lactam ring in the area δ 5.2-5.8 and δ 6.2-6.8 and the aromatic proton appeared from the region δ 6.64-7.70 ppm. The elemental analysis and molecular ion pinnacles of compounds (3a-s) are reliable with the assigned structure.

Pharmacology

The newly synthesized compounds 3a-s tried for tits in vitro antimicrobial activities against clinical isolates of Gram-positive microbes Staphylococcus aureus and its standard reference (ATCC 6538P), Gram-negative bacteria Pseudomonas aeruginosa, it’s a stock reference (ACTT-BAA-427), Escherichia coli (ATCC 8739) and Candida albicans. Along these lines, a progression of azido β-lactams having the thiazole moiety into one molecular framework has been synthesized, which shows slight to direct antibacterial and antifungal action.

SD – Standard Doxycycline, SF – Standard Fluconazole

All compounds 3a-s demonstrated critical action against Gram-negative Pseudomonas aeruginosa, while 3b and 3l showed articulated activity against Escherichia coli. Among every one of the compounds tried against Gram +vie Staphylococcus aureus, just 3b, 3g, and 3l repressed the development of microorganisms altogether while different compounds demonstrated moderate activity (Ghatole et al., 2014).

The antifungal movement results in Table 3 uncovered that mixes compounds 3e, 3f, 3h, 3l, 3n, and 3o had a generally high inhibitory impact on Candida albicans, the remainder of the compound displayed moderate action.

Structure-activity relationships (SAR)

Structure-activity relationships, a great stencil used for tailoring effective lead molecules, were studied. We tested all the synthesized compounds against bacteria and fungus with moderate to high antimicrobial activity.

Our hybrid molecule may consider as a template scaffold in which one can insert substituents at different positions to enhance the specificity of microorganisms as antibacterial and antifungal activities. Our hybrid molecules possess ring A (Fig. 8) as a substituted aromatic ring in the thiazole skeleton at Ortho, Meta, and Para position. Ring B constitutes the thiazole subunit; ring C is a four-membered cyclic β-lactam ring having the azido group as a substitute at the C8 location, ring D derived from substituting aromatic aldehyde. The compound 3l displayed maximum antibacterial and antifungal activity at 200 µg/ml due to -OH, -Cl, and -Br substitution on ring A at the ortho, meta, position and –NO2 substitution at 3rd position of ring D. which enhanced the synergistic effects leading to compounds having excellent activity in comparison to other compounds. Either with unsubstituted or substituted aromatic ring D., It is also interesting to note that the compounds 3e, 3f, 3h, 3n and 3o exhibit significant antifungal activity, at 200 µg/ml. That revel substitution of –OH in all products at ortho position and replacement of –Br and –I at meta position of aromatic ring A and ring B is essential for modulation of the hydrophilic, which may enhance its antifungal activity. The presence of electron-withdrawing group (-NO2) and donating group like -N(CH3) 2, -OCH3 as substituents at the 3rd and 4th positions in rings D may attenuate the antifungal activity. Other compounds exhibited moderate activity against fungi and bacteria due to the presence of -CH3, OH, Cl at ring A, and –OCH3, -NO2, substituents at ring D irrespective of inductive effects.

Molecular modelling

A comparative study done with the known drugs viz. ceftaroline, methicillin, penicillin, doxycycline, fluconazole, teicoplanin, telavancin to the active site of the clinical mutant E150K from MRSA (PDB ID-4BL2) made for better comprehension of their antibiotic action. Docking score depicted in Table 4.

The computational test was directed by PyRx programming with eight best conformational positions out of that the best posture esteem detailed in Table 4. Considering the above information without much of a stretch foresee that the standard compounds with active sites of chains A and B. The ceftaroline and teicoplanin had the most significant negative binding energy relations with other approved drugs.

From the binding energy score and atomic interaction between the ligand and protein dynamic site of chain A and Chain B, a portion of the perceptions portrayed. The coupling score of ligand 3i (-5.0Kcal/mole) with chain A had the most noteworthy negative value, which is comparable to standard drug ceftaroline (-5.5Kcal/ mole) yet not exactly teicoplanin (-6.3Kcal/mole). With chain A had 3f, 3l, 3j, 3m, and 3p demonstrates the same binding score while 3c had a rundown score. In chain B interaction 3k (-5.6Kcal/mol) had a most elevated value which is comparable with the standard teicoplanin (- 6.0Kcal/mole) among the variously blended compound which displayed in Tables 5 and 6.

Comparative interaction study of 3l (-5.0Kcal/mole) vs 3f (-4.9 Kcal/mole) and 3c (-4.4Kcal/mole) LIGPLOT plot with the active site of chain A

The red circles and ovals in each plot show protein residues that are in equal 3D positions to the tailings. Hydrogen bonds appeared green dotted lines, while the spoked bends speak to deposits making non- bonded contacts with the ligand.

HIS311 – Imidazole functional group of histidine demonstrates hydrogen holding with terminal nitrogen of azide functional group of ligands 3i (3.19A0) and 3f (3.25A0), respectively. The terminal nitrogen of azide in 3i and nitrogen directly connected azetidine ring in hydrophobic association with HIS311, imidazole ring carbon, and the straightforwardly appended secondary carbon with the imidazole ring, while in the case of 3f there is no hydrophobic communication.

GLN140 – The iminol form of the glutamine side chain indicates 2.98A0 and 2.94A0 hydrogen holding with terminal nitrogen of azide functional group of 3i and 3c; with this equivalent nitrogen in 3c connection and center nitrogen of azide group demonstrates hydrophobic interaction with carbonyl carbon of amide functional group of GLN140. In any case, 3f just had hydrogen bonding of terminal nitrogen of azide bunch with iminol form of the glutamine side chain. With this GLN140 having the carbonyl carbon and oxygen of the amide functional group had hydrophobic communication with two methyls and the nitrogen atom of N-dimethyl benzene substituted ring.

GLY135 – The carboxylic acid group of GLY135 indicates hydrogen bonding, i.e., 2.90A0 with terminal nitrogen of azide group of 3f with no other hydrophobic association. While 3i and 3c additionally demonstrate hydrogen holding 3.24A0) and hydrophobic association with carbonyl carbon and -NH2 of GLY135.

VAL302 – The primary amine of VAL302 shows hydrogen bonding with 3i and 3f of radius 3.03A0 and 3.01A0, respectively, and hydrophobic interaction with the carbonyl oxygen of azetidine ring.

THR300 – THR300 had a carboxylic acid and primary amine group, which is in hydrogen bonding with the nitrogen of thiazole ring (3.06A0) and hydroxy group (3.03A0) of a substituted phenyl ring of ligand 3f. The nitrogen of the thiazole ring and hydroxy group of 3i had hydrogen bonding with carboxylic acid (3.1 ), and a primary amine group (2.96A0) of THR300 expansion to this 3i demonstrates the number of hydrophobic communications with THR300 which isn’t seen with 3f as portrayed in Fig. 9.

HIS143– We look at the interaction of histidine 143 and 311 with the ligand 3i and 3f; both amino acids demonstrate hydrogen holding, yet the bond length is diverse in HIS143. The carboxylic acid group interacts with a hydroxy group of 3i with hydrogen bond length 3.02A0, while the same carboxylic acid group of HIS143 shows 3.13A0 hydrogen bonding with the hydroxy group of 3f.

Further, HIA143 and 3f ligand don’t demonstrate any hydrophobic interaction, while carbonyl carbon of HIS143 had hydrophobic interaction with bromine and a hydroxy group, which likewise associated in hydrogen bonding. The non-ligand residue, i.e., ALA310, ARG110 in hydrophobic contact with the 3i and 3f while in a case on protein-ligand interaction ALA310 and 3c in hydrophobic connection along with HIS311, THR300, HIS143, and ARG298 that used for hydrogen bonding in protein-ligand (3f and 3i) interaction.

Comparative interaction study of 3k (-5.6 Kcal/mole) vs. list binding energy score 3r (-4.2 Kcal/mole) LIGPLOT plot with the active site of chain B

In the comparative plot of 3k and 3r (Fig. 10), there is three amino acids via HIS785, THR942, and VAL944 that are in equivalent 3D positions to the residues. Out of this, only THR942 commonly had hydrogen bonding with the nitrogen of the thiazole ring in 3k and methoxy oxygen of a substituted benzene ring of 3r. The 3k had hydrogen bonding (3.26A0) with a carboxylic acid group, while 3r shows hydrogen bonding (3.05A0) with a hydroxy group of THR942. But only 3k ligand shows hydrophobic interaction with THR942.

HIS785 shows a hydrogen bond (3.18A0) with terminal nitrogen of azide group and had numerous hydrophobic interactions with the nitrogen of azide, carbon of azetidine, and carbon of chlorophenyl ring of 3k; in case of 3r ligand, it had only hydrophobic contact. 3k shows two hydrogen bonding viz 3.01A0 and 3.24A0 with VAL944 while it is absent in 3r. Another amino acid interaction is GLN782, ILE943, and ILE786 with 3k and 3r with the active site of chain B are GLU787 and ILE951.

SwissADME pharmacokinetics, physicochemical, medicinal properties study The operational highlights of these molecules entered in the SwissADME site (http://swissadme.ch) utilizing the ChemAxon’s Marvin JS structure drawing instrument. Auxiliary highlights of a pharmacophore impact including bioavailability, transport properties, empathy to proteins, reactivity, poisonous quality, and metabolic steadiness. Incomparable to swissADME is the bioavailability radar (Daina et al., 2017) that gives a graphical preview of the medication similarity parameters of an orally available bioactive drug. The drug resemblance diagram displayed as a hexagon (Figs. 11 and 12) with each of the vertices speaking to a parameter that characterizes a bioavailable drug. The pink region inside the hexagon speaks to the ideal range for every property (lipophilicity: XLOGP3 between −0.7 and +5.0, size: polarity: TPSA (Topological Polar Surface Area) somewhere in the field of 20 and 130 Å2, MW somewhere in the range of 150 and 500 g/mol, solubility: log S not higher than 6, flexibility: close to 9 rotatable bonds, and saturation: part of carbons in the sp3 hybridization at least 0.25) (Table 7) .

By comparing the bioavailability radar between the Schiff base and the β-lactam (Fig. 10), it observed that the insaturation axes of the synthesized β-lactam decrease, but the polarity and insolubility range along the axes increase.

The drug resemblance properties of the fused compound and standard drug are articulated to by the red mutilated hexagon inside the pink shade (Figs. 11 and 12). The molecules fall within the drug-likeness parameter of a bioavailable drug are depicted in Table 8. SwissADME likewise has computational channels that incorporate Ghote et al. (1999), Egan et al. (2000), Veber et al. (2002) and Muegee et al. (2001) created by top pharmaceutical organizations and cheminfomaticians to assess the drug resemblance of molecules.

The Ghose screen quantitatively describes molecules dependent on figured physicochemical property profiles that incorporate log P, molar refractivity (MR), molecular weight (MW), and several atoms. The passing scope of determined log P (ClogP) is between – 0.4 and 5.6. For MW, the passing extent is somewhere in the range of 160 and 480. For MR, the passing reach is somewhere in the field of 40 and 130, and for the total number of atoms, the passing extent is between 20 and 70 atoms in a small molecule. Our compounds 2a, d, q, while 3a-e, k, o, p, q, and fluconazole standard tested to qualify the Ghose qualifying criteria, but the molecule 2m and 3f-j, l-n, r and 3s out of the qualifying range (Table 9).

Veber (GSK) filter model represents molecules as druglike on the off chance that they have ten or less rotatable bonds and a PSA equivalent to or under 140 Å with 12 or less H-bond donors and acceptors.

Egan (Pharmacia) filter gives an expectation of drug assimilation dependent on physical procedures engaged with film absorbency of a molecule. Significantly, the Egan computational model for human passive intestinal absorption (HIA) of molecule represents dynamic carriage and efflux components and is, in this way, vigorous in foreseeing adaptation of drugs. The Egan violation only observed in 2m; 3d-h, j,l,n,p,r-s, and the doxycycline standard drug (Table 9).

Muegge (Bayer filter) model is a database-free pharmacophore point screen that separates between druglike and nondrug-like matter. It depends on the perception that non-drugs are frequently less functionalized. Four purposeful themes characterized to be significant in druglike molecules and incorporate hydroxyl, amine, ketone, and sulfonyl groups. In this manner, a base check of well-characterized pharmacophore focuses is required to pass the screen. The manifestation of these efficient themes ensures hydrogen-holding capacities that are basic for explicit drug cooperation with its objectives. These serviceable groups can consolidate to what the Muegge model alludes to as pharmacophore points. The pharmacophore emphases incorporate amine, amide, alcohol, ketone, sulfone, sulfonamide, carboxylic acid, carbamate, guanidine, amidine, urea, and active ester groups. These pharmacophore efforts in molecules possibly give critical communications with the objective protein. From the screening data, the synthesized compound 2m and 3bd, f-p, r-s along with doxycycline that they don’t have the recommended functional group for the interaction with the target protein suggested by the Muegge.

PAINS, Break and Leadlikeness screening

PAINS (pan-assay interference screening) that often gives false favorable chemical properties results in high-throughput screens. PAINS tend to react non-specifically with numerous biological targets rather than specifically affecting one anticipated goal.

PAINS (pan-assay interference screening) that regularly give false favorable synthetic properties bring about high-throughput screens. PAINS will, in general, respond non-specifically with various biological targets as opposed to explicitly influencing one anticipated objective.

SwissADME evaluation did not post any PAINS alert except 2a, d, m, q, and standard doxycycline and fluconazole molecules (Table 10).

In another choicemodel, Brenk et al. (2008) considered composites thatare smaller and less hydrophobic and not those characterized by “Lipinski’s standard of 5” to enlarge open doors for lead streamlining. After the prohibition of compounds with possibly mutagenic, reactive, and unfavorable groups, for example, nitro, sulfates, phosphates, 2-halopyridines, and thiols. Brenk model confines the ClogP/ ClogD to sandwiched between zero and four, the quantity of hydrogen-bond donors and acceptors to less than 4 and 7, individually, and the number of substantial atoms to in the range of 10 and 27. Furthermore, just compounds with restricted entanglement characterized as less than eight rotatable bonds, less than five ring structures, and no ring structures with more than two fused rings are considered medicinal. The 2a, d, m, q with all the β-lactams derivatives and standard doxycycline flouted break rule.

Leadlikeness tests proposed to furnish leads with great kinship in high-throughput screens that take into account the detection and manipulation of new exchanges in the lead advancement stage (Table 10). Only the standard fluconazole drugs passed all the leadlikness criteria, while all the synthesized compounds with the standard doxycycline fail in leadlikness.

P-glycoprotein and CYP enzyme activity prediction

SwissADME additionally empowers the estimation for a compound to be a substrate of p-glycoprotein (P-gp) or inhibitor of the cytochrome p450 isoenzymes (CYP isoenzymes). P-gp is broadly dispersed and communicated in the intestinal epithelium where it thrusts xenobiotics, for example, medicates over into the intestinal lumen and in the delicate endothelial cells making the blood-brain barrier where it propels them once again into the vessels. CYP isoenzymes are in charge of the biotransformation of drugs (Ogu & Maxa, 2000). Drug digestion through CYP isoenzymes is a significant determinant of drug connections that can prompt to drug toxicities and diminished pharmacological impact. The models return “Yes“ or “No“ if the molecule under examination has a higher likelihood to be substrate or non-substrate of P-gp or inhibitor or non-inhibitor of a given CYP. The screening results tabulated (Table 11).

HIA and BBB prediction

Appropriate to P-gp and CYP protein energy is human gastrointestinal ingestion (HIA) and blood-brain barrier infiltration (BBB). SwissADME ‘BOILEDegg’ (Fig. 13) permits for assessment of HIA as an element of the situation of the molecules in the WLOGP-versus-TPSA referential. The white section of the ‘BOILEDegg’ is for a high possibility of reflexive adaptation by the gastrointestinal tract, and the yellow area (yolk) is for a high probability of cerebrum entrance, which is shown by all the Schiff base while all the β-lactams are out of the region. Yolk and white zones are not fundamentally unrelated. With this, the points are shaded in blue whenever anticipated as effectively effluxed by P-gp (PGP+) and in red predicted as non-substrate of P-gp (PGP−).

HIA and BBB are subject to water solubility and lipophilicity of the drug. Two topological approaches to foresee water solubility comprised of SwissADME. The first is an execution of the ESOL (Delaney, 2004) model, and the subsequent one modified by Fagerberg et al. (2015). SILICON-IT created SwissADME third indicator for solubility. All anticipated qualities are the decimal logarithm of the molar solubility in water (log S).

The ESOL, Ali, and Silicons IT screening solubility of all the synthesized compounds depicted in Table 12. Even the standard drugs are in the range of solubility to very soluble. Consensus Log p is the average value of all Log P evaluated with various lipophilicity criteria (Table 13).

Experimental

General

Every one of the reactions was conveyed under the stipulated conditions, utilizing freshly prepared thiazole, ionic liquid, and pure solvents. The open capillary technique was used to decide the melting point of the compound and are uncorrected. The refined dissolvable was utilized to perform TLC on silica gel G. All the chemicals were obtained from SD. Fine chemicals of AR grade. 1H NMR and 13C NMR spectra recorded from DMSO-d6 solutions on a Brucker AC 400 (MHz). TMS as an internal standard for detailing the chemical shift in1H NMR. KBr discs method used to IR spectra on a Perkin Elmer 1800 spectrophotometer and mass spectra portrayal finished with a GC-MS (70ev). All tertiary alkyl amines concentrated H2SO4, cyclohexanone, and aromatic aldehydes bought from SD. Fine chemicals of AR grades.

Synthesis of N-(4-methoxybenzylidene)-4-(4-methoxyphenyl) thiazol-2-amine N-(4-methoxybenzylidene)-4-(4-methoxyphenyl) thiazol-2-amine was synthesized by the reaction between 4-(4-methoxyphenyl) thiazol-2-amine and anisaldehyde in the presence of conc.H2SO4 in ethanolic medium gives the desired product. The yield was 87%. M.P.: 187 0C; IR (KBr): νmaxcm-1 1610, 771, 2930cm-1; 1H-NMR: δ 8.12 (1H, s), 7.12-7.18 (2H, d), 7.16-7.18 (2H, d), 6.88-6.90 (2H, d), 6.69-6.71 (2H, d), 5.61 (1H, s), 3.75 (6H, s)

Synthesis of 3-azido-4-(4methoxyphenyl)-1-(4-(4-methoxyphenyl thiazol-2-yl) azetidin-2-one 3a

To a 10 mL round bottom flask containing ionic liquid [bmim][PF6 ] (3.0 mL) and 1 mL of [Et3NH] +[HSO4] -, N-(4-methoxybenzylidene)-4-(4-methoxyphenyl) thiazol-2-amine, 2a (0.13mmol) was added. The reaction mixture was stirred at RT for 15 min. azidoacetic acid (0.13mmol) was added to the reaction mixture and continued stirring for 4 hours at 45-500C. After completion of the reaction (monitored by TLC), the solid product obtained triturated with solvent ether in 3 fractions (3x5mL). The organic layer was evaporated under reduced pressure to get the ionic liquid back for reuse. The resulting product was dried and purified by crystallized from alcohol, acetic acid; to furnish the product in yield was 75%.

M.P.: 138 0C; IR (KBr): νmaxcm-13000, 2930, 2124, 1720 cm-1; 1H-NMR : δ 3.75 (s, 6H, Ar-(OCH3) 2), 5.63-5.68 (d, 1H, J 18.84Hz, He), 6.24-6.24 (d, 1H, J 13.52Hz, Hf), 6.64-6.66 (d, 2H, J 8.64Hz, Ha,b), 6.81-6.83 (d, 2H, J 8.76Hz, Hj,k), 7.15-7.21 (d, 4H, Hc,d,k,h), 7.67 (s, 1H, Hg); 13C NMR : δ 56.92, 70.66, 71.61, 80.93, 84.73, 98.21, 117.37, 119.12, 129.16, 136.31, 138.09, 142.04, 146.81, 163.75, 165.0168.75, 170.18; MS (m/z) : (407.1M+); Elemental Analysis (C20H17N503S): Calculated: C: 58.96, H: 4.21, N: 17.19; Found: C: 58.24, H: 4.19, N: 17.12

All compounds were prepared by the aforementioned procedure; all reactions were monitored by TLC after specified times.

3-azido-4-(4-methoxyphenyl)-1-(4-p-tolyithiazol-2-yl)azetidin-2-one 3b

M.P.: 205 0C; IR (KBr): νmaxcm-1 3110, 2098, 1690, 780cm-1; 1H-NMR : δ 2.38 (s, 3H, Ar-CH3), 3.78 (s, 3H, Ar-OCH3 ), 5.80-5.83 (d, 1H, J 10.92Hz, He), 6.36 (d, 1H, J 6Hz, Hf), 7.44 (s, 1H, Hg), 7.50-7.52 (d, 2H, J 6.72Hz, Ha,b), 7.63-7.70 (d, 2H, Hi,j), 7.81-7.94 (d, 4H, Hc,d,h,k); 13C NMR : δ 22.3, 57.8, 59.3, 65.2, 100.2, 115.7, 127.1, 127.8, 130.1, 136.3, 138.5, 148.2, 158.2, 161.2, 162.3; MS (m/z) : (391.1M+); Elemental Analysis (C20H17N5O2S) : Calculated: C: 61.37, H: 4.38, N: 17.89; Found: C: 61.21, H: 4.32, N: 17.78.

3-azido-4-(4-(dimethylamino)phenyl)-1-(4-p-tolylthiazol-2-yl)azetidin-2-one 3c

M.P.: 230 0C; IR (KBr): νmax cm-1 2997, 2980, 2111, 1697, 1340, 762cm-1; 1H-NMR : δ 2.79 (s, 3H, Ar-CH3), 2.99 (s, 6H, Ar-N(CH3) 2), 5.40-5.42 (d, 1H, J 8.92Hz, He), 5.78-5.79 (d, 1H, J 2.68Hz, Hf), 6.58 (s, 1H, Hg), 6.68-6.70 (d, 2H, J 8.04Hz, Ha,b), 7.10-7.12 (d, 2H, J 7.96Hz, Hi,j), 7.36-7.38 (d, 2H, J 8.04Hz, Hc,d), 7.65-7.66 (d, 2H, J 3.68Hz, Hk,h); 13C NMR : δ 24.2, 40.2, 59.4, 66.7, 101.2, 114.3, 128.6, 129.9, 130.7, 131.3, 138.6, 149.2, 149.8, 161.5; MS (m/z) : (404M+); Elemental Analysis (C21H20N6OS) : Calculated: C: 62.86, H: 4.98, N: 20.78; Found: C: 62.81, H: 4.98, N: 20.73

3-azido-4-(3-nitrophenyl)-1-(4-p-tolylthiazol-2-yl)azetidin-2-one 3d

M.P.: 170 0C; IR (KBr): νmaxcm-12990, 2087, 1692, 1080, 790cm-1; 1H-NMR : δ 2.00 (s, 3H, Ar-CH3 ), 5.48-5.49 (d, 1H, J 1.72Hz, He), 5.96-5.98 (d, 1H, J 8.4Hz, Hf), 6.50 (s, 1H, Hg), 6.68-6.70 (d, 1H, J 8.04Hz), 6.90-6.91 (d, 2H, J 4.6Hz, Hi,j), 7.48-7.49 (d, 3H, J 4.12Hz, Hc,b,m), 7.65-7.66 (d, 2H, J 5.2Hz, Hk,h);13C NMR : δ 23.1, 58.2, 64.7, 99.3, 119.7, 123.6, 128.7, 131.4, 132.2, 134.6, 139.8, 145.5, 149.6, 163.2; MS (m/z) : (406.08M+); Elemental Analysis (C19H14N6O3S): Calculated: C: 56.15, H: 3.47, N: 20.68; Found: C: 56.13 , H: 3.45, N: 20.61.

3-azido-1-(4-(2-hydroxy-5-methylphenyl)thiazol-2-yl)4-(4-methoxyphenyl) azetidin-2-one 3e

M.P.: 170 0C; IR (KBr): ν maxcm-1 3100, 2990, 2109, 1962, 680cm -1; 1H-NMR : δ 2.77 (s, 3H, Ar-CH 3), 3.76 (s, 3H, Ar-OCH 3 ), 5.55-5.58 (d, 1H, J 15.08Hz, Hf), 6.87-6.89 (d, 1H, J 5.16Hz, He), 6.50 (s, 1H, Hg), 6.68-6.70 (d, 2H, J 8.04Hz, Ha,b), 6.90-6.91 (d, 2H, J 4.6Hz, Hc,d), 7.39-7.49 (t, 1H, Hl), 7.65-7.66 (d, 1H, J 5.2Hz, Hi), 7.82 (s, 1H, Hk), 9.15 (s, 1H, Ar-OH); 13 C NMR : δ 25.1, 57.2, 59.8, 66.7, 99.7, 115.5, 118.8, 121.3, 127.4, 132.1134.5, 138.2, 149.3, 154.3, 159.6, 161.8; MS (m/z) : (407.11M +); Elemental Analysis (C 20H17N5O3S): Calculated: C: 58.96, H: 4.4, N: 17.19; Found: C: 58.95, H: 4.38, N: 17.14.

3-azido-4-(4-(dimethylamino)phenyl)-1-(4-(2hydroxy-3-iodo-5-methylphenyl) thiazol-2-yl)azetidin-2-one 3f

M.P.: 186 0C; IR (KBr): ν maxcm-1 3120, 2999, 2112, 769cm -1; 1H-NMR : δ 2.32 (s, 3H, Ar-CH 3), 2.80 (s, 6H, Ar-N(CH 3) 2), 5.49-5.50 (d, 1H, J 3.12Hz, Hf), 5.82-5.83 (d, 1H, J 6.4Hz, He), 6.58 (s, 1H, Hg), 6.68-6.70 (d, 2H, J 8.04Hz, Ha,b), 7.10-7.12 (d, 2H, J 7.96Hz, Hc,d), 7.36-7.38 (d, 1H, J 8.04Hz, Hl), 7.65-7.66 (d, 1H, J 3.68Hz, Hk), 8.82 (s, 1H, Ar-OH); 13C NMR : δ 25.5, 41.2, 60.3, 65.1, 88.6, 102.1, 115.6, 124.2, 128.3, 132.2, 135.5, 140.2, 148.1, 1149.5, 160.1, 162.3; MS (m/z) : (546M +); Elemental Analysis (C21H19IN6 O2 S) : Calculated: C: 46.16, H: 3.51, N: 15.38; Found: C: 46.14, H: 3.50, N: 15.31.

3-azido-1-(4-(3-bromo-2-hydroxy-5-methylphenyl)thiaazol-2-yl)-4(4 (dimethylamino)phenyl)azetidin-2-one 3g

M.P.: 100 0C; IR (KBr): νmaxcm-1 3110, 2098, 1701, 1390, 724, 670cm-1; 1H-NMR : δ 2.16 (s, 3H, Ar-CH3), 4.15 (s, 6H, Ar-N(CH3) 2), 5.15-5.18 (d, 1H, J 13.92Hz, He), 5.75-5.76 (d, 1H, J 5.00Hz, Hf), 7.20-7.20 (d, 2H, J 2.68Hz), 7.387.41 (q, 2H), 7.62 (s, 1H, Hg), 7.73-7.77 (d, 1H, J 5.00Hz, Hk), 7.85-7.87 (d, 1H, J 9.2Hz, Hl), 11.96 (s, 1H, Ar-OH); 13C NMR : δ 26.4, 40.3, 59.8, 67.3, 101.2, 115.3, 125.1, 129.5, 131.2, 136.2, 136.9, 138.5, 149.2, 150.5, 153.3, 162.1; MS (m/z) : (500.05M+); Elemental Analysis (C21H19BrN6O2S) : Calculated: C: 50.51, H: 3.85, N: 16.83; Found: C: 50.48, H: 3.82, N: 16.82.

3-azido-1-(4-(3-bromo-2-hydroxy-5-methylphenyl)thiaazol-2-yl)-4(4-methoxyphenyl) azetidin-2-one 3h

M.P.: 230 0C; IR (KBr): ν maxcm-1 3012, 2991, 2108, 1590, 1690, 735, 680cm-1; 1H-NMR : δ 2.35 (s, 3H, Ar-CH3 ), 4.10 (s, 3H, Ar-OCH3), 5.44-5.47 (d, 1H, J 13.56Hz, He), 6.18-6.19 (d, 1H, J 6.12Hz, Hf), 7.58-7.59 (d, 2H, J 3.12Hz, Ha,b), 7.63-7.64 (d, 2H), 7.85-7.86 (d, 1H, J 4.64Hz, Hl), 8.01-8.04 (d, 1H, J 9.8Hz, Hk), 8.27 (s, 1H, Hg), 12.21 (s, 1H, Ar-OH);13C NMR : δ 21.1, 57.3, 59.8, 64.1, 99.8, 116.3, 124.3, 128.7, 130.3, 133.5, 138.9, 139.2, 149.8, 152.4, 159.8, 161.2; MS (m/z) : (487.01M+); Analysis (C20H16BrN5O3S) : Calculated: C: 49.39, H: 3.32, N: 14.40; Found: C: 49.35, H: 3.30, N: 14.38.

3-azido-1-(4-(3-bromo-2-hydroxy-5-methylphenyl)thiaazol-2-yl)-4(4-chlorophenyl) azetidin-2-one 3i

M.P.: 94 0C; IR (KBr): νmaxcm-13440, 3105, 2089, 1710, 682.1cm-1 ; 1H-NMR : δ 2.16 (s, 3H, Ar-CH3), 5.39-5.40 (d, 1H, J 4.36Hz, He), 6.00-6.02 (d, 1H, J 10.68Hz, Hf), 7.31 (s, 1H, Hg), 7.62-7.64 (d, 2H, J 8.36Hz, Ha,b), 7.75-7.76 (d, 2H, J 6.4Hz, Hc,d), 7.87-7.88 (d, 1H, J 2.96Hz, Hl), 8.21-8.25 (d, 1H, J 15.52Hz, Hk), 12.13 (s, 1H, Ar-OH); 13C NMR : δ 23.7, 58.1, 65.7, 102.1, 114.2, 124.3, 129.9, 132.7, 134.4, 136.8, 138.5, 144.3, 149.8, 153.0, 162.2; MS (m/z) : (490.96M+); Elemental Analysis (C19H13BrClN5O2S) : Calculated: C: 46.50, H: 2.67, N: 14.27; Found: C: 46.48, H: 2.65, N: 14.26.

3-azido-1-(4-(3-bromo-5-chloro-2-hydroxyphenyl)thiaazol-2-yl) -4(4-methoxyphenyl) azetidin-2-one 3j

M.P.: 135 0C; IR (KBr): νmaxcm-1 3500, 2067, 1530, 1340, 721, 675cm-1; 1H-NMR : δ 4.15 (s, 3H, Ar-OCH3), 5.41-5.42 (d, 1H, J 5.12Hz, He), 5.71-5.72 (d, 1H, J 3.28Hz, Hf), 7.58-7.59 (d, 2H, J 4.04Hz, Ha,b), 7.61-7.62 (d, 2H, J 1.16Hz, Hc,d), 8.01-8.04 (d, 1H, J 1.92Hz, Hl ), 8.12-8.15 (d, 1H, J 2.08Hz, Hk), 8.27 (s, 1H, Hg), 11.50 (s, 1H, Ar-OH); 13C NMR : δ 55.9, 60.0, 85.3, 100.2, 114.1, 115.7, 124.2, 127.8, 128.9, 129.6, 131.9, 135.8, 148.2, 153.0, 158.7, 160.4; MS (m/z): (506.96M+); Elemental Analysis (C19H13BrClN5O3S) : Calculated: C: 45.03, H: 2.59, N: 13.82; Found: C: 45.02, H: 2.53, N: 13.80.

3-azido-1-(4-(5-chloro-2-hydroxyphenyl)thiazol-2-yl)-4-(4-chlorophenyl) azetidin-2-one 3k

M.P.: 110 0C; IR (KBr): νmaxcm-1 3480, 2089, 1603, 1645, 1010, 767cm-1; 1H-NMR : δ 5.25-5.26 (d, 1H, J 4.24Hz, Hf), 5.89-5.92 (d, 1H, J 10.58Hz, He), 6.68-6.70 (d, 2H, J 8.00Hz, Ha,b), 6.89-6.91 (d, 2H, J 8.8Hz, Hc,d), 7.12-7.38 (m, 2H, Hi,l), 7.65-7.66 (d, 1H, J 4.28Hz, Hk), 7.98 (s, 1H, Hg), 9.01 (s, 1H, Ar-OH); 13C NMR : δ 61.2, 64.2, 101.2, 118.9, 123.4, 128.4, 129.8, 132.3, 134.8, 144.5, 149.7, 155.6, 163.7; MS (m/z) : (431.00M+); Elemental Analysis (C18H11Cl2N5O2S) : Calculated: C: 50.01, H: 2.56, N: 16.20; Found: C: 50.01, H: 2.47, N: 16.18.

3-azido-1-(4-(3-bromo-5-chloro-2-hydroxyphenyl)thiazol-2-yl)-4-(4-nitrophenyl) azetidin-2-one 3l

M.P.:140 0C; IR (KBr): νmaxcm-1 3477, 2101, 1640, 700cm-1; 1H-NMR : δ 5.025.21 (d, 1H, J 5.68Hz, He), 5.84-5.86 (d, 1H, J 8.00Hz, Hf), 6.84-6.85 (d, 1H, J 4.48Hz, Hk), 7.16-7.38 (m, 4H, Hc,b,m), 7.65-7.66 (d, 1H, J 4.28Hz, Hl), 7.98 (s, 1H, Hg), 9.17 (s, 1H, Ar-OH); 13C NMR : δ 57.8, 67.2, 103.2, 117.3, 118.1, 124.2, 125.2, 128.2, 130.5, 134.5136.7, 147.6, 149.2, 155.3, 160.1; MS (m/z) : (521.9M+); Elemental Analysis (C18H10BrClN6O4S) : Calculated: C: 41.44, H: 1.93, N: 16.11; Found: C: 41.42, H: 1.87, N: 16.09.

3-azido-1-(4-(3-bromo-5-chloro-2-hydroxyphenyl)thiazol-2-yl)-4-(3-chlorophenyl ) azetidin-2-one 3m

M.P.: 146 0C; IR (KBr): νmaxcm-1 3492, 3133, 2086, 710, 667cm-1; 1H-NMR : δ 5.54-5.56 (d, 1H, J 9.52Hz, He), 5.92-5.93 (d, 1H, J 3.8Hz, Hf), 6.86-6.88 (d, 1H, J 6.52Hz, Hk), 7.11-7.46 (m, 4H, Hc,b,m,d), 7.68-7.70 (d, 1H, J 4.32Hz, Hl), 8.99 (s, 1H, Hg), 9.03 (s, 1H, Ar-OH); 13C NMR : δ 59.5, 65.5, 99.2, 117.2, 125.2, 126.5, 127.8, 129.1, 130.0, 132.5, 135.5, 147.8, 149.8, 155.2, 160.7; MS (m/z) : (510.9M+); Elemental Analysis (C18H 10BrCl2N5O2S) : Calculated: C: 42.29, H: 1.97, N: 13.70; Found: C: 42.27, H: 1.95, N: 13.67.

3-azido-1-(4-(3-bromo-5-chloro-2-hydroxyphenyl)thiazol-2-yl-4-(3-dimethylamino) phenyl) azetidin-2-one 3n

M.P.: >320 0C; IR (KBr): νmaxcm-1 3450, 2987, 2109, 1680, 1510cm-1; 1 H-NMR : δ 2.60 (s, 6H, Ar-N(CH3) 2), 5.34-5.35 (d, 1H, J 1.84Hz, He), 5.91-5.92 (d, 1H, J 2.16Hz, Hf), 7.50 (s, 1H, Hg), 7.52-7.57 (d, 2H, J 20.7Hz, Ha,b), 7.59-7.67 (t, 1H), 7.74-7.77 (d, 1H, J 13.12Hz, Hk), 8.05-8.10 (q, 1H), 8.40 (s, 1H), 11.94 (s, 1H, Ar-OH); 13C NMR : δ 40.2, 60.3, 65.1, 98.2, 114.1, 115.7, 124.2, 127.8, 129.6, 131.9, 133.0, 147.6, 153.0, 160.4; MS (m/z) : (519.99M+); Elemental Analysis (C20H16BrClN6O2S) : Calculated: C: 46.21, H: 3.10, N: 16.17; Found: C: 46.19, H: 3.09, N: 16.15.

3-azido-1-(4-(5-chloro-2-hydroxyphenyl)thiazol-2-yl)-4-phenyl azetidin-2-one 3o

M.P.: 94 0C; IR (KBr): ν maxcm-1 3452, 2088, 1740, 1650, 676cm-1 ; 1H-NMR : δ 5.41-5.43 (d, 1H, J 8.6Hz, He), 5.88-5.89 (d, 1H, J 3.4Hz, Hf), 6.52 (s, 1H, Hg), 6.83-6.85 (d, 1H, J 9.04Hz, Hk), 7.12-7.38 (m, 6H, Ha,b,c,d,l,m), 7.65-7.67 (d, 1H, J 9.04Hz, Hi), 9.03 (s, 1H, Ar-OH); 13C NMR : δ 60.2, 65.5, 101.7, 117.4, 123.8, 127.3, 129.8, 132.4, 144.5, 148.7, 154.3, 160.8; MS (m/z) : (397.04M+); Elemental Analysis (C18H12ClN5O2S) : Calculated: C: 54.34, H: 3.04, N: 17.60 ; Found: C: 54.30, H: 3.02, N: 17.58.

3-azido-4-(furan-3-yl)-1-(4-(2-hydroxy-5-methyl-3-nitrophenyl) thiazol-2-yl) azetidin-2-one 3p

M.P.: 169 0 C; IR (KBr): νmaxcm-13466, 3109, 2110, 769, 682cm-1; 1H-NMR : δ 2.56 (s, 3H, Ar-CH3), 6.17-6.19 (d, 1H, J 6.88Hz, He), 6.21-6.23 (d, 1H, J 6.88Hz, Hf), 6.21-6.23 (d, 1H, J 6.96Hz), 7.39-7.39 (d, 1H, J 2.32Hz), 7.50-7.53 (q, 1H), 7.67-7.69 (d, 1H, J 8.88Hz), 7.78-7.81 (m, 1H), 7.92-7.94 (d, 1H, J 9.04Hz), 9.23 (s, 1H, Ar-OH); 13C NMR : δ 28.3, 43.3, 67.8, 100.2, 111.3, 123.8, 126.6, 129.8, 134.2, 138.6, 139.4, 139.9, 144.4, 149.8, 162.4; MS (m/z) : (412.0M+); Elemental Analysis (C17H12N6O5S) : Calculated: C: 49.51, H: 2.93, N: 20.38; Found: C: 49.48, H: 2.91, N: 20.38.

3-azido-1-(4-(2-hydroxy-5methylphenyl)thiazol-2-yl)-4-phenyl azetidin-2-one 3q

M.P.: 184 0C; IR (KBr): νmaxcm-13115, 2935, 2080, 1650, 1604, 750, 685cm-1; 1H-NMR : δ 1.59 (s, 3H, Ar-CH3 ), 5.40-5.40 (d, 1H, J 3.16Hz, Hf), 5.69-5.70 (d, 1H, J 3.32Hz, He), 6.96-6.99 (d, 1H, J 8.88Hz, Hi), 7.44-7.49 (m, 5H, Ha,b,c,d,m), 7.57-7.58 (d, 1H, J 2.12Hz, Hi), 7.63 (s, 1H, Hg), 7.98 (s, 1H, Hk), 12.75 (s, 1H, Ar-OH); 13C NMR : δ 24.6, 60.0, 65.5, 99.8, 116.3, 120.5, 126.8, 127.0, 127.6, 130.5, 131.5, 143.5, 148.5, 152.3, 160.4; MS (m/z) : (377.09M+); Elemental Analysis (C19H15N 5O2S) : Calculated: C: 60.46, H: 4.01, N: 18.56; Found: C: 60.46, H: 4.01, N: 18.55.

3-azido-1-(4-(5-chloro-2-hydroxy-3-iodophenyl)thiazol-2-yl)-4-(4-methoxyphenyl)azetidin-2-one 3r

M.P. : 145 0C; IR (KBr): νmaxcm-1 3100, 2850, 2104, 1715, 690, 520cm-1; 1H-NMR : δ 3.68 (s, 3H, Ar-OCH3), 5.81-5.84 (d, 1H, J 12.6Hz, He), 6.35-6.37 (d, 1H, J 6.68Hz, Hf), 7.44 (s, 1H, Hg), 7.50-7.52 (d, 1H, J 6.72Hz, Hl), 7.70-7.73 (d, 1H, J 4.00Hz, Hk), 7.86-7.88 (d, 2H, J 8.4Hz, Ha,b), 7.92-7.94 (d, 2H, J 9.08Hz, Hc,d), 9.17 (s, 1H, Ar-OH); 13C NMR : δ 55.9, 62.0, 66.3, 89.4, 100.0, 114.1, 123.6, 127.8, 129.2, 130.8, 135.5, 139.2, 149. 7, 158.7, 160.4,

163.2; MS (m/z) : (552.95M+); Elemental Analysis (C19H13ClN5O3S) : Calculated: C: 41.21, H: 2.37, N: 12.65; Found: C: 41.19, H: 2.36, N: 12.64.

3-azido-1-(4-(5-chloro-2-hydroxy-3-iodophenyl)thiazol-2-yl)-4-(4-(dimethylamino)phenyl) azetidin-2-one 3s

M.P.: 132 0C; IR (KBr): νmaxcm-13130, 2930, 2077, 1695, 665, 534cm-1; 1H-NMR : δ 2.80 (s, 6H, Ar-N(CH3) 2), 5.49-5.50 (d, 1H, J 3.28Hz, He), 5.82-5.83 (d, 1H, J 3.44Hz, Hf), 6.55 (s, 1H, Hg), 6.66-6.70 (d, 2H, J 16.2Hz, Ha,b), 7.15-7.17 (d, 2H, J 8.52Hz, Hc,d), 7.36-7.38 (d, 1H, J 6.84Hz, Hl), 7.66-7.68 (d, 1H, J 8.08Hz, Hk), 8.82 (s, 1H, Ar-OH); 13C NMR : δ 40.3, 59.8, 64.3, 89.7, 101.2, 116.3, 121.7, 126.6, 128.6, 130.7, 133.3, 140.5, 147.6, 148.2, 162.2, 164.8; MS (m/z) : (565.98M+); Elemental Analysis (C20H16ClN6O2S) : Calculated: C: 42.38, H: 2.85, N: 14.83; Found: C: 42.37, H: 2.84, N: 14.81.

Biological assay

The minimum inhibitory concentration (MIC) exercises completed in 50, 100, 200µg/ml DMSO by a disc-plate method utilizing the nutrient agar mediums. Gentamycin, doxycycline, and fluconazole used as standards, the minimum inhibitory concentration for the most dynamic strategies (Chang et al., 1997). Filter paper disc method (Vincent & Vincent, 1944) using the Hi-Media agar mediums is employed to study the antibacterial activity of 3a-s against Gram-positive bacteria Staphylococcus aureus, Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli bacterial strain and Candida Albicans as antifungal strain. Preparation of nutrient broth, subculture, and base layer medium has done as per the standard procedure. Each test compound (40mg) dissolved in 2mL of DMSO, which used as a sample solution. Different concentrations (200, 100, 50µg/mL) of the solution prepared by the dilution method. The sample size for all the compounds fixed as 10µL. The paper disc of each test compound placed on the previously inoculated petri dish with the microorganisms. After 24hr and 48hr treatment for antibacterial and antifungal study, a zone of inhibition produced by each compound measured in mm.

Computational details

All the ligand used was made using ChemDraw 3D (ultra-Software., n.d.). Before the docking calculation of the ligands, the structure was lower in energy and then docked by using PyRx (Trott & Olson, 2010). The crystal structure for the complex with an inhibitor downloaded from Protein Data Bank (http://www.rscb. org/) as a PDB file. The active site of the docked protein was found out by Argus Lab 4.0 (software., n.d.), which used for the docking in the PyRX.

The downloaded protein of the PBP2a clinical mutant E150K from MRSA (PDB ID- 4BL2) contain chain A and B with chloride and cadmium ion as an interacting ligand. The protein contains two chains A, and B has 20519 atoms with net charge is zero and having 57051 valence electrons. The protein-ligand interaction studied with the active binding site of chains A and B. In the chain A contains nineteen active binding sites viz. ALA301, ARG110, ARG298, ASN307, ASP209, GLN137, GLN140, GLN207, GLU145, GLY135, HIS143, HIS232, HIS311, ILE309, LYS229, LYS230, THR210, THR300 and VAL302 in chain B contain twenty-one active binding site that is VLA952, ARG752, ASN949, ASN1211, ASP851, ASP1215, GLN779, GLN782, GLN849, GLU787, GLY777, HIS785, HIS874, HIS953, ILE786, ILE943, ILE951, LYS1093, MET778, THR942, and VAL944. The chain A and B with the residues, water, and hetero group within a radius of 2.72A0 refined for further cleaned by ascertaining the hybridization and introducing the H-atoms to the protein residue with the removal of water molecules. The docking with PyRx (Autodock) was conducted vina search space of dimension size x = 55.4589539785, y = 37.7989937242, z = 43.9275995514, center x = 22.7466396916, y = 37.934731349, z = 23.0487215997 for chain A and for chain B size x = 69.314661892, y = 33.6138645394, z = 90.4083639469, x = 1.67346816513, y = 38.8272936698, z = 45.4518205308 with eight exhaustiveness. The LIGPLO T+ version V.1.4.5 (Laskowski & Swindells, 2011) used to find the multiple ligand-protein interaction diagram.

SIB site http://www.swissadme.ch retrieved to in an internet browser that shows the lodging page of SwissADME. Our synthesized and categorized molecules 3a-s and standard drug were a contribution for estimation of ADME, physicochemistry, drug-likeness similarity, pharmacokinetics, and therapeutic properties. The effort zones itself include a molecular sketcher dependent on ChemAxon’s Marvin JS (http://www.chemaxon.com) that enabled the client to draw and alter 2D chemical structures. The structures moved as a rundown to the right-hand side of the lodging page, which is the real contribution for computational calculation. The list made to contain one input molecule for each line, characterized by the simplified molecular-input line-entry system (SMILES), and results are introduced for every molecule in tables, graphically, and as an excel spreadsheet.

Acknowledgments. Authors are thankful to the Department of Pharmacy, Nagpur for IR spectral analysis, and SAIF, Chandigarh, for 1H NMR spectral analysis. We are grateful to SAIF, Pune University, for mass spectral analysis of all newly synthesized compounds. We pay special thanks to Dr. Mrs. Sandhya Saoji for antimicrobial activity.

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