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Visible-light active, heterogeneous, and organic photocatalysts exhibit a more sustainable and environmentally friendly alternative to classical metal-based catalysts. Two-dimensional covalent organic frameworks (2D-COFs) with permanent porosity, columnar π-arrays and excellent stability, that can become an excellent platform for heterogeneous photocatalysis of organic transformations. Here we report a predesigned imine-based COF with electron donor and acceptor structure. And new framework possesses large surface area, high crystallinity, outstanding stability and broad absorption range in the visible-light region as well as good photoelectric response characteristics. Importantly, it was found to be a highly effective heterogeneous photocatalyst for reductive dehalogenation of phenacyl bromide derivatives and α-alkylation of aldehydes under irradiation of visible-light. In addition, the COF gave good recyclability and could be reused after a simple separation manipulation. The current present still reveals a great prospect for 2D-COFs as metal-free, heterogeneous photocatalysts for organic transformations.

A novel mixed phosphonium–iodonium ylide was synthesized by alkylation of 5-phenyl-5H-dibenzophosphole with phenacyl bromide followed by deprotonation and oxidation of the resulting phosphonium ylide with (diacetoxyiodo)- benzene. The influence of the cyclic nature of the phosphonium moiety on the dynamic E/Z isomerism in the mixed ylide is discussed.

The research was aimed to synthesize heterocyclic derivatives containing thiazole fused p-hydroxybenzohydazide for antimycobacterial activity. As, literature survey reveals various substitutions on thiazole fused p-hydroxybenzohydazide moiety show a variety of remarkable activities, the new derivatives of thiazole fused p-hydroxybenzohydazide was prepared by using various substitutions on R and R’ positions. Considering various pharmacological activities the present work is designed to club thiazole fused p-hydroxybenzohydazide moiety with different phenacyl bromide and isothiocynate moieties. Synthetic studies started with reaction of p-hydroxymethylbenzoate (1) which on amination with hydrazine hydrate leads to form common intermediate p-hydroxybenzohydrazide (2). This intermediate (2) when undergoes nucleophilic addition reaction with aryl isothiocyanates were resulted in the formation of thiosemicarbazides (III.a-III.d). The cyclization reaction (step-III) was carried out by using different phenacyl bromides, actual cyclization takes place by using sodium acetate. Step-III was resulted in the formation of final compounds (IV.a-IV.h). All synthesized compounds were further characterized by melting point. The compounds showed single spot in TLC which assured the completion of reactions and the purity of the compounds. The compounds were synthesized by appropriate synthetic route. The melting points of compounds were determined. The melting points of compounds were determined and were uncorrected. Thin layer chromatography was carried out by using suitable solvent system selected on the basis of solubility and polarity. The Rf value was determined. All the newly synthesized compounds were subjected for characterization by Rotational and Vibrational spectra (IR), Nuclear Magnetic Resonance (NMR), Mass spectroscopy (MS) and C, H, N analysis. The newly synthesized by compounds were screened for antimycobacterial activity by radiometric method.

Effective methodology that activates selectively either end of a carbon–carbon triple bond requires key challenge of differentiating between the multitude of C C bonds present in complex organic molecule. The synthetic strategy exploited the electronic biases within the substrate and successfully achieved site–selective [bmIm]OH catalyzed C C bond functionalization under mild reaction conditions. This resulted in C-2-selective addition of phenacyl bromide on p-substituted phenyl acetylene and C-1 selective addition on the o-substituted phenyl acetylene leading to C C bond formation. The reaction proceeded smoothly with excellent yield under ambient conditions. This report demonstrates the progress on the catalytic activity of recyclable [bmIm]OH for selective C C bond formation.

Two new series of bis-thiazoles 6a-f and bis-thiazolones 9a-d were prepared via reacting bis-thiosemicarbazone 3 with hydrazonoyl chloride derivatives 4a-f and 7a-d, respectively, in dioxane under basic conditions. Another group of bis-thiazole derivatives 12a-h was prepared by reacting bis-thiosemicarbazone 3 with each of phenacyl bromide derivatives 10a-h under a similar reaction protocol. A plausible mechanism was proposed. Structural elucidation of the new products was established using both elemental and spectrometric/spectroscopic analyses. Structural, electronic, and the pharmacological characteristics of the prepared molecules were investigated with DFT calculations. Antibacterial and antifungal activities of the new bis-thiazoles were screened and compared with vancomycin and amphotericin B as antimicrobial standards. Molecular docking studies on the promising candidate compounds, with the lowest minimum inhibitory concentrations (MIC), were performed with SAP2 of C. albicans and FabI of S. aureus and P. aeruginosa.

New attempts and insights are reported on the electrochemical potentiostatic reduction of phenacyl bromides in DMF. Now we present the evidences on the original mechanism proposal, the definitive characterization of the obtained products and additional results of complementary electrochemical anodic reactions.

A novel and atom-economic protocol for the synthesis of thiazole-2-imine derivatives was developed. Synthesis of thiazole-2-imine derivatives from primary amines, phenyl isothiocyanate and phenacyl bromide derivatives by the CoFe2O4@SiO2-PA-CC-Guanidine-SA magnetic nanocatalyst in excellent yields was reported. This nanocatalyst is easily separated from the reaction mixture and can be reused for several times. For the characterization of the catalyst used of Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and vibrating-sample magnetometry (VSM) techniques.

In the present manuscript, a series of steroidal thiazole derivatives (4–6, 8) have been synthesized in efficient manner by one step reaction methodology employing microwave irradiation. The synthesis involves the reaction of steroidal ketones (1–3, 7) with thiosemicarbazide and phenacyl bromide. Structural assignment of the products was confirmed on the basis of IR, 1H NMR, 13C NMR, MS and analytical data. The synthesized compounds were screened for in vitro antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. In addition, the products 4–6, 8 were also tested for pBR322 DNA cleavage activity, genotoxicity, reactive oxygen species (ROS) production and RBC hemolysis. Molecular docking analysis was carried out to validate the specific binding mode of the newly synthesized compounds into the active site of DNA. Docking showed formation of more stable complexes of compounds 4 and 8 with the free binding energies − 8.1 and − 8 kcal/mol, respectively. Hence, it could be suggested that the steroidal compounds bearing a core thiazole scaffold would be a potent biological agent.

Ten new pyridine linked various substituted thiazole hybrids through (hydrazonomethyl)phenoxy-acetamide spacer were synthesized. The synthetic strategy was based on the reaction of the precursor 2-(4-((2-carbamothioylhydrazono)methyl)phenoxy)-N-(pyridin-2-yl)acetamide (3) with various α-halogenated carbonyl compounds (namely; phenacyl bromides, ethyl bromoacetate, diethyl bromomalonate and 3-chloropentane-2,4-dione). Moreover, the cytotoxicity properties of the synthesized compounds have been studied against liver carcinoma (HepG2), laryngeal carcinoma (Hep-2), prostate cancer (PC3), breast cancer (MCF-7) and normal fibroblast cells (WI38). The pyridine-thiazole compounds 7 and 10 revealed promising anticancer activity against MCF-7 and HepG2 cell lines with IC50 values in the range 5.36–8.76 μM compared to the activity of 5-fluorouracil. Docking study provided valuable insights for binding sites of the synthesized compounds with Rho-associated protein kinase (ROCK-1).

A new series of N- and S-alkylated products of 3-aryl-1H,3H-quinazolin-2,4-dione and 3-aryl-2-mercapto-3H-quinazolin-4-one, respectively, were prepared in good yields via efficient nucleophilic substitution reaction of the SH and NH substrates with methyl iodide, ethyl bromoacetate, allyl bromide, propagyl bromide, 2-bromoethanol, 1,3-dibromopropane or phenacyl bromide in DMF as a solvent and anhydrous potassium carbonate. The quinazolin-2,4-dione favored the N-alkylation while the 2-mercapto-3H-quinazolin-4-one goes via the S-alkylation. DFT reactivity studies showed that the former have the N-site with higher nucleophilicity compared to the O-site. In contrast, the S-site is the more nucleophilic centre than the N-atom of the latter. The structures of the synthesized products have been established on the basis of their melting point (m.p), IR and 1HNMR data. The molecular structures of the products were calculated using the DFT B3LYP/6-311G(d,p) method. The electronic and spectroscopic properties (Uv–Vis and NMR spectra) were calculated using the same level of theory. The chemical reactivity descriptors that could help to understand the biological activity of the products are also predicted.

A facile synthesis of tricyclic skeleton of alkaloid 261C has been achieved by a double [3+2] cycloaddition of p-methoxypyridinium phenacyl bromide and maleimides with high diastereoselectivity. The initial Hammett analysis suggested that the most stable resonance form of pyridinium ylide is the one, the negative charge of which is widely dispersed in the pyridine ring.

Plasmonic Au nanocrystals (NCs) are incorporated into covalent organic frameworks (COFs) with precisely modulated distributions to improve the efficiency of electron-hole separation and optimize the charge-carrier utilization. Specifically, through balancing the rate of dynamic covalent reactions and assembly of NCs, sparsely dispersed Au NCs (AuSP/COFs) or the close packed ones (AuCP/COFs) in COFs are fabricated, in which the contributions of electron acceptors/cocatalysts on the catalytic properties of Au/COFs composites are addressed by EPR, PL, and electrochemical measurements. Au3SP/COFs shows the best photocatalytic performances in photodegradation of RhB (remove >95 % in 120 min, kw=1.8 min−1 g−1) and dehalogenation of phenacyl bromide (conversion >99 %, selectivity of acetophenone ∼92.8 %) under visible light irradiation, which are associated with accelerated electron transfer, increased available Au/COFs Schottky junctions and boosted interfacial reaction kinetics. Overall, this work contributes to the fundamental understanding of the how spatial distributions of NCs in COFs affect the photocatalytic performances.

Two naphthoquinone derivatives, i.e. 5-hydroxy-1,4-naphthoquinone (5HNQ) and 2-hydroxy-1,4-naphthoquinone (2HNQ), combined with different additives such as diphenyliodonium hexafluorophosphate (Iod), N-vinylcarbazole (NVK), phenacyl bromide (R-Br), N-phenyl glycine (NPG) and ethyl 4-dimethylamino benzoate (EDB), are investigated as photoinitiating systems (PISs) for free radical polymerization of trimethylolpropane triacrylate (TMPTA) and cationic polymerization of triethyleneglycol divinyl ether (DVE-3). The photopolymerization of the thiol-ene system trimethylolpropane tris(3-mercaptopropionate) (Trithiol)/DVE-3 with 5HNQ or 2HNQ based PISs are also investigated. 5HNQ shows maximum absorption in visible light region (blue light) which thus has the potential to perform under the irradiation of blue LED light. For the free radical polymerization of TMPTA, 5HNQ/Iod/NPG shows the highest photoinitiating ability among all the naphthoquinone derivative-based PISs, while 2HNQ-based systems are inefficient. The addition of Trithiol to TMPTA can significantly increase the double bond conversion of TMPTA during the photopolymerization. For the cationic photopolymerization of DVE-3, 2HNQ/Iod shows the highest photoinitiating ability among all the naphthoquinone derivative-based photoinitiating systems. 5HNQ-based systems also demonstrate good photoinitiation ability for DVE-3, but with slower polymerization rate compared to 2HNQ-based systems. In thiol-ene photopolymerization, 5HNQ PISs shows better photoinitiation ability than 2HNQ PIs systems. The results illustrate that the position of hydroxyl group in 1,4-naphthoquinone molecules plays an important role on photoinitiation ability of naphthoquinone derivatives. Steady state photolysis and electron spin resonance trapping experiments are also carried out to evaluate the relevant photochemical mechanism.

Halogenated and non-halogenated N-(4-phenyl-3-aroyl-2(3H)-ylidene) substituted acetamides were prepared by base-catalyzed cyclization of corresponding acetyl thioureas with phenacyl bromide. The synthesized compounds were structurally characterized by 1H NMR and 13C NMR spectroscopy and were screened against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzyme inhibition activities. Molecular docking studies, drug-like profiling and kinetic analysis were performed to further investigate the inhibition mechanism of the compounds. This study provided useful insights into the design and development of novel dual inhibitors, in addition to understanding the mechanism by which such drugs interact with targets and exert their biochemical action. All the compounds showed superior inhibition profile compared to the standards possessing sub-micromolar and micromolar IC50 values for AChE and BChE, respectively. Docking simulations revealed that the compound 6g showed strong binding inside the active site gorges of both AChE and BChE. An excellent agreement was obtained as the best docked poses showed important binding features mostly based on interactions due to aromatic moieties and oxygen atoms of the compound. Cation-pi/pi-pi interactions together with hydrogen bond forces were the key players responsible for ligand anchoring in the active sites. The striking results accomplished both in docking computations and experimental findings ascertained that the compound 6g can serve as a scaffold for both AChE and BChE inhibition.

Eco-friendly methods of heterocyclic synthesis are highly important in view of pharmacology. This synthetic chemistry deals with the application of environmental friendly chemical compounds synthesis using microwave methods. Greener method of synthesis of benzo-fused indolizines like ethyl 4-Bromo-1-(substituted-benzoyl)pyrrolo[1,2-a]quinoline-3-carboxylate analoguos 1a-n using the one-pot method with 3‑bromo quinolone, phenacyl bromide and electron-deficient alkynes in the presence of triethylamine base with acetonitrile as a solvent. The structures of all the newly synthesized pyrrolo[1,2-a]quinoline have been confirmed by spectroscopic techniques. All the synthesized test compounds were screened for their antibacterial activity using six different types of gram-positive and gram-negative bacterial strains. The compounds 1a, 1k, and 1l exhibited a significant zone of inhibition against all six bacterial strains, and the test compound 1i showed potent free radical scavenging activity with the highest percentage inhibition of 49.27 at 100 µg/mL.

A series of new hydrazonothiazolines (3a-v) was obtained in good to excellent yields (79–96%) via cyclization of the appropriate thiosemicarbazones with phenacyl bromide. The targeted compounds were characterized by advanced spectroscopic techniques, such as FTIR, 1HNMR, 13CNMR and ESI-MS. The structure of compounds 3n and 3v was unambiguously confirmed by single crystal X-ray analysis. All compounds displayed enhanced inhibitory activity against urease enzyme with IC50 values in range of 1.73 ± 1.57–27.3 ± 0.655 μM when compared to standard thiourea (IC50 = 20.8 ± 0.75 µM). The structure-activity relationship studies demonstrated that the activity of this series is due the central thiazole ring that interacts with nickel atoms in the active site of urease enzyme. Moreover, molecular docking studies were carried out to investigate the binding mode of all active compounds and an inactive (3u) with the active site of the urease enzyme. The docking results are in complete agreement with the experimental finding.

A highly efficient domino Michael/cyclization reaction was developed for the synthesis of cyclopentanols and cyclopentenes with four and three stereogenic centers that were generated in one-pot reaction conditions with high diastereoselectivity. The reactions proceeded through a one-pot three-component reaction of β-nitrostyrenes, malononitrile and phenacyl bromide derivatives in basic media at room temperature.

A simple, efficient and eco-friendly method has been developed for quinoxaline synthesis from inexpensive and readily available diamines and phenacyl bromides by catalyst- and additive-free protocol.

A new organocatalytic approach to the synthesis of ceramide trafficking inhibitor HPA-12 has been described starting from phenacyl bromide. The strategy involves chiral CBS reduction of γ-ketoester and proline-catalyzed α-amination reaction of aldehyde followed by reduction as the key chirality inducing steps.

A novel one-pot, five-component synthesis of 1-(alkylimino)-5,5-dicyano-3a-aryloctahydro-3-oxacyclobuta[cd]pentalene-1a,2,5a,5b(2H,3aH)-tetracarboxylates is described. A mixture of phenacyl bromide, malononitrile, isocyanide, and two equivalents of a dialkyl acetylenedicarboxylate undergoes a novel 1:1:1:2 addition reaction at ambient temperature in absolute ethanol to produce diastereoselectively the title compounds in good yields.

A simple, rapid, efficient, and environmentally benign procedure for synthesis of polysubstituted pyrroles has been achieved by the three-component reaction of amines, phenacyl bromide and dialkyl acetylenedicarboxylates under solvent free conditions using nano structures of ZnO as catalyst. Different morphologies such as nanorods and nanosheets of catalysis have been synthesized by simple reflux method using sodium dodecylsulfate (SDS) and applied in this reaction. Nanorod ZnO catalyst exhibited a significant enhancement in the yield of the desired product. The catalyst exhibited remarkable reusable activity.

An asymmetric synthesis of 2-arylpiperazines starting from phenacyl bromides, a variety of which are easily available, has been established. The synthesis features a CBS reduction of phenacyl bromide to provide optically enriched compounds, an SN2 reaction of 1,2,3-oxathiazolidine 2-oxides with an azide anion with invert of configuration, and construction of the piperazine ring via reduction of piperazine-2,3-diones.

An efficient regioselective synthesis of 3-aryl imidazo[1,2-a]pyridines, 5-aryl imidazo[2,1-b]thiazoles, and 3-aryl benzo[d]imidazo[2,1-b][1,3]thiazoles is described by the reaction of phenacyl bromide with heterocyclic amine in the presence of DABCO under aqueous medium. The method is applicable for a variety of substituted phenacyl bromides as well as 2-amino-heterocycles. An aqueous reaction medium, regioselectivity, mild reaction condition, and high yield of products are the important features of this protocol.

The three-component domino reactions of pyridine/isoquinoline, phenacyl bromide, and substituted (E)-N-hydroxyarylimidoyl chloride in the presence of triethylamine afforded a series of 2-arylimidazo[1,2-a]pyridines and 2-arylimidazo[2,1-a]isoquinolines. This one pot three-component transformation presumably proceeds via ylide generation/annulation/fragmentation/dehydration domino sequence of reactions.

A series of novel 2-(3,5-diphenyl-4,5-dihydro-1H-pyrazol-1-yl)-4-phenylthiazoles have been prepared by a three-component cyclo-condensation of various chalcones, thiosemicarbazide and phenacyl bromide. The easy work-up of the products, rapid reaction, and mild conditions are notable features of this protocol. The reaction was efficiently catalyzed in one-pot by a few drops of HCl in EtOH under reflux conditions providing the title compounds in moderate to high yields. The antibacterial activity of the selected products was examined. Some products exhibit promising activities.

A simple and efficient synthesis of highly substituted pyrroles was achieved in water medium via multi-component strategy, using amine, DMAD/DEAD as well as phenacyl bromide catalyzed by β-CD. Utilizing this protocol various pyrrole derivatives were synthesized in good to excellent yields.

The di- N -functionalized macrocycle 2,13-bis(2-phenacyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[16.4.0. 1.18 0 7.12 ]docosane (H 2 L 2 ) bearing two N -CH 2 COC 6 H 5 groups has been prepared by the reaction of 3,14-dimethyl-2,6,13,17-tetraazatricyclo[16.4.0.0 7.12 ]docosane (L 1 ) with phenacyl bromide. Interestingly, H 2 L 2 reacts with Ni 2+ ion to form two geometric isomers, trans -[Ni(H 2 L 2 )] 2+ and cis -[Ni(H 2 L 2 )] 2+ . The axial Ni–O ( N -CH 2 COC 6 H 5 group) bond distance (2.080(2) A) of trans -[Ni(H 2 L 2 )](ClO 4 ) 2 ·2DMSO is shorter than the in-plane Ni–N distances (2.096(2) and 2.100(2) A). However, the Ni–O distances (2.105(2) and 2.124(2) A) of cis -[Ni(H 2 L 2 )](ClO 4 ) 2 ·H 2 O are considerably longer than the Ni–N distances (2.053(2)–2.086(2) A). Each N -CH 2 COC 6 H 5 group of trans -[Ni(H 2 L 2 )] 2+ and cis -[Ni(H 2 L 2 )] 2+ exists as its keto form in the solid state and in various solvents. Two N -CH 2 COC 6 H 5 groups of trans -[Ni(H 2 L 2 )] 2+ are readily deprotonated in basic aqueous solutions, producing the enolate form trans -[Ni(L 2 )]. On the other hand, cis -[Ni(H 2 L 2 )] 2+ undergoes deprotonation to yield cis -[Ni(HL 2 )] + , in which one N -CH 2 COC 6 H 5 group is not deprotonated, under similar conditions.

The reaction of anthrone 1 with 4-aminoantipyrine and thiosemicarbazide afforded 4-(anthracen-9(10H)-ylideneamino)-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one 2 and anthracen-9(10H)-one thiosemicarbazone 5 , respectively. Oxidation of compound 2 with potassium permanganate gave 4-(anthracen-9(10H)-ylideneamino)-1-methyl-3-oxo-2-phenyl-2,3-dihydro-1H pyrazole-5-carboxylic acid 3 which on reaction with o -phenylenediamine gave 4-(anthracen-9(10H)-ylideneamino)-5-(1H-benzimidazol-2-yl)-1-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one 4 . Furthermore, compound 5 was condensed with different substituted phenacyl bromide to give a series of 2-(anthracen-9(10H)-ylidenehydrazono)-5-substituted-2,3-dihydro-1H-thiazole 6a – g . Compound 5 also reacted with chloroacetic acid affording 2-(anthracen-9(10H)-ylidenehydrazono)thiazolidin-4-one 7 . The structures of all the products have been determined by elemental analysis and spectral studies. All compounds have been screened for their antibacterial and antifungal studies. The results are summarized in Tables 1 and 2 .

A series of 2,5,6-trisubstituted imidazo[2,1- b ][1,3,4]-thiadiazole derivatives 4 ( a – k ) have been prepared by reaction of 2-amino-5-cyclopropyl-1,3,4-thiadiazole and an appropriate phenacyl bromide. Further 5-bromo 5 ( a – k ) and 5-thiocyanato 6 ( a – k ) derivatives were synthesized in order to study the effect of these substituents on antitumor activity. Structures of these compounds were established by IR, 1 H NMR, 13 C NMR and Mass spectroscopy. Seven compounds were granted NSC code at National Cancer Institute (NCI), USA for anticancer activity at a single high dose (10 −5 M) in full NCI 60 cell panel. Among the compounds tested, 5-bromo-6-(4-chlorophenyl)-2-cyclopropylimidazo[2,1- b ][1,3,4]thiadiazole 5b ( NSC D - 96022 / 1 ) was found to be the most active candidate of the series at five dose level screening with degree of selectivity toward Leukemic cancer cell line.

A high yielding environmentally benign protocol has been developed for the synthesis of pyrrolo[2,1-a]isoquinoline using chromone-3-carboxaldehyde, isoquinoline and phenacyl bromide/bromoacetic acid ester as reagents in aqueous micellar medium. The method is operationally simple and more effective compared to the previous methods in terms of the yield of the products as well as the reaction time.

The base-catalyzed reaction of benzoyl acetone 1 with phenyl isothiocyanate yields the non-isolable intermediate 2 . Treatment of 2 with dilute HCl afforded the corresponding thiocarbamoyl derivative 3 . Reaction of the intermediate 2 with phenacyl bromide, ethyl bromoacetate, chloroacetonitrile, chloroacetyl chloride, bromodiethyl malonate and chloroacetone afforded the corresponding thiophene derivatives 5 , 8 , 15 and 17 . The thiocarbamoyl derivative 3 reacts with arylazophenacyl bromide and/or hydrazine hydrate to afford the corresponding thiadiazole and pyrazole derivatives 20a – c and 22 , respectively. These new synthesized compounds show generally a moderate molluscicidal activity to Biomphalaria alexandrina snails.

Aryl, alkyl, and sugar-derived isoselenocyanates were prepared by a one-pot procedure starting from the corresponding formamides, using triphosgene as a dehydrating agent, triethylamine, and black selenium powder. The preparation of sugar selenoureas by coupling of O-protected sugar-derived isoselenocyanates with different amines, and by coupling of unprotected glycopyranosyl amines with phenyl isoselenocyanate was also accomplished. The synthesis of a glucopyranos-2-yl-selenazole starting from O-protected 2-amino-2-deoxy-d-glucose by coupling with benzoyl isoselenocyanate, Se-alkylation with phenacyl bromide, and acid-catalyzed dehydration is also reported. Unprotected N-(β-d-glucopyranosyl)-N′-phenylselenourea was transformed into a 1,2-trans-fused bicyclic isourea upon treatment with aqueous hydrogen peroxide; the same isourea was prepared by a one-pot three-step procedure from β-d-glycopyranosylamine by thiophosgenation, coupling with aniline, and HgO-mediated desulfurization.

Some new nitroimidazole derivatives have been synthesized by treating 4,5-dinitro- and 2-methyl-4,5-dinitroimidazoles with epoxypropane, epichlorohydrin or phenacyl bromide in alkylation reactions. The nitro group in N-substituted 4,5-dinitro- and 2-methyl-4,5-dinitroimidazoles has been replaced with primary and secondary amines to afford 4-amino-5-nitroimidazole derivatives. Some of the compounds have been tested for their antioxidant and antifungal properties against fungi species acting on timber. Nearly all of them have shown significant antioxidant activity in comparison with that of tocopherol, which is used as a reference substance. Two compounds from those tested have revealed very strong fungistatic activity against Sclerophoma pityophila.

The key dinitrile intermediates 4a–d were synthesized by reaction of phenacyl bromide 1 and the appropriate 2-amino-5-bromopyridines to yield 3a–d. Suzuki coupling of 3a–d with 4-cyanophenylboronic acid yielded the 2,6-bis(4-cyanophenyl)-imidazo[1,2-a]pyridine derivatives 4a–d. The bis-amidoximes 5a–d, obtained from 4a–d by the action of hydroxylamine, were converted to the bis-O-acetoxyamidoximes which on catalytic hydrogenation in a mixture of ethanol/ethyl acetate gave the acetate salts of 2,6-bis[4-(amidinophenyl)]-imidazo[1,2-a]pyridines 7a–d. In contrast, catalytic hydrogenation of the bis-O-acetoxyamidoxime of 5a in glacial acetic acid gave the saturated analogue 2,6-bis[4-(amidinophenyl)]-5,6,7,8-tetrahydro-imidazo[1,2-a]pyridine 8. O-Methylation of the amidoximes 5a–d gave the N-methoxyamidines 6a–d. The diamidines showed strong DNA binding affinity, were very active in vitro against T. b. r. exhibiting IC50 values between 7 and 38 nM, but were less effective against P. f. with IC50 values between 23 and 92 nM. Two of the diamidines 7c and 7d were slightly more active than furamidine but less active than azafuramidine in the T. b. r. STIB900 mouse model. Only one prodrug 6b showed moderate activity in the same mouse model.

We synthesized poly-substituted pyrrole derivatives 4a–e, 7a–c and 10a–d from the reaction of phenacyl bromide and the aza-Baylis–Hillman adducts 1a–d or their rearranged derivatives 5a–e. The pyrroles were synthesized via the successive N-alkylation, Michael addition, elimination of p-toluenesulfinic acid and oxidative aromatization processes.

The Rap–Stoermer reaction of salicylaldehydes with diverse phenacyl bromide and phenacyl iodides proceeded cleanly to afford various functionalized benzofurans in excellent yields under base-mediated solvent free microwave irradiation conditions.

Pathogenic microbes have mutated and developed resistance to the latest range of antibiotics, which has kept synthetic chemist hunting for better and least toxic antimicrobial agents. Cyclocondensation of substituted anilines with 3-phenyl-2-propenoic acid yielded Phenyl-(substituted)-quinolin-2-one derivatives (1a–1t). In the next step phenylquinolin-2-one acetic acid derivatives (2a–2t) were prepared by the treatment of (1a–1t) with chloroacetic acid. Further (2a–2t) derivatives were reacted with thiocarbohydrazide to obtain a series of 4-amino-5-sulfanyl-4,5-dihydro-1,2,4-triazolo-4-pheny-(substituted)-quinolin-2-one derivatives (3a–3t). Then condensation of (3a–3t) with phenacyl bromide provided series of fused heterocyclic derivatives of 4-phenyl-1-({6-phenyl-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl}methyl)-(substituted)-1,2-dihydro quinolin-2-one (4a–4t). Structures of these newly synthesized derivatives were established by elemental analysis, FT-IR, 1H NMR and Mass spectroscopy. Final derivatives (4a–4t) were screened for their in vitro antibacterial and antifungal activities against the standard drugs Ampicillin and Fluconazole respectively. The compounds 4d, 4g and 4j showed potent activity against all the studied microbes. Particularly compounds substituted with halogen groups at para position of phenylquinoline ring exhibited significant antimicrobial activity against studied microbes. Keywords: Antimicrobial, Cyclocondensation, Phenylquinoline, Triazolothiadiazine

2-R-Pyridines (R CN, CH NOH and COMe) with phenacyl bromide gave the corresponding quaternary bicyclic ring system containing one ring junction nitrogen and one extra nitrogen or oxygen atom (1–3). Their structures were confirmed by 1H, 13C and 15NMR spectra in DMSO-d6 solution using 2D NMR techniques (COSY, NEOSY, HETCOR and HMBC). The structure of 1-oxo-3-phenyl-pyrido[1,2a]pyrazinium bromide monohydrate, 1, was unambiguously confirmed by X-ray crystallography. The crystals of 1 are monoclinic, space group P21/n, with a=7.730(2) A, b=14.094(3) A, c=12.553(3) A, β=106.18(3)°, V=1311.3(5) A3 and Z=4 (at 110 K). The isolated entities of 1–3 were analyzed by the B3LYP/6-31G(d,p) level of theory in order to get information on the electrostatic interaction between the oppositely charged groups.

Thioureido-acetamides ( 1 ) are quantitatively accessible by gas–solid reaction of amines with thiohydantoins. They are useful starting materials for various heterocyclic syntheses in one-pot cascade reactions with excellent atom economy: 2-iminothiazoles ( 5 ) are quantitatively formed from 1 and phenacyl bromide in the solid state. Thioparabanic acids ( 9 ) are easily accessible from oxalyl dichloride and 1 . Benzils react with 1 to afford functionalized 5,5-diaryl-thiohydantoins ( 14 ) and dimethylacetylene dicarboxylate gives 2-imino-5-methylene-thiazolidine-4-ones ( 17 ) and ( 18 ) upon reaction with 1 . The one-pot syntheses of imidazo[1,2-c]pyrimidines ( 25 ) and ( 28 ) from 1 with benzaldehydes and ethyl cyanoacetate or malodinitrile are benign new accesses to these important heterocycles. All product structures are determined from spectroscopic and chemical data and preferred tautomers are judged by DFT calculations at the B3LYP/6-31G∗ level.

Tellurium, but not selenium, reacts with phenacyl bromide (ω-bromoacetophenone) to give diphenacyltellurium dibromide (PhCOCH2)2TeBr2 (1), which represents the first example of a functionally substituted organotellurium halide to have been prepared directly from elemental tellurium and an organic halide. Metathesis of 1 with KI affords the crystalline diiodide, (PhCOCH2)2TeI2 (2), but halide–pseudohalide exchange does not proceed with KSCN or AgN3. Compounds 1 and 2 have been characterized by elemental analyses, IR, 1H- and 13C-NMR and mass spectrometry. Coordinative interaction of both the carbonyl groups in 1 and 2, in solid state as well as in solution, is indicated by IR spectra. Crystal and molecular structures of the dihalides were determined by X-ray diffraction method. Compounds 1 and 2 are isostructural and crystallize in the monoclinic system with space group P21/n. The primary geometry about the central Te atom in both the compounds is Ψ-trigonal-bipyramidal with axial halogens. Stereochemically active lone pair of electrons occupies the equatorial plane along with methylene C atoms of the organic ligands. The Te⋯O intramolecular attractive interactions, though weak [Te⋯O(1), Te⋯O(2): 2.938, 2.912 A in 1 and 2.877, 2.818 A in 2] appear to saturate tellurium(IV) atom coordinatively so as to prevent intermolecular Te⋯Br/I interactions. However, there is evidence of weak intermolecular TeBr⋯H(methylene) secondary interactions in compound 1, leading to the formation of supramolecular assemblies.

A number of 3-(4-substituted benzoylmethyl)-2-benzoxazolinones have been synthesized by reacting with 2-benzoxazolinone and 4-substituted phenacyl bromide in ethanol. Their chemical structures were confirmed by IR, 1H NMR and elemental analysis. For screening antimicrobial activity, minimum inhibitory concentration (MIC) values were determined against two Gram positive, one Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus) and three yeast-like the fungi (Candida albicans, Candida krusei, Candida parapsilosis).

Asymmetric Darzens reaction catalyzed by chiral selenides is described. A novel Lewis acid/Bronsted base catalyst formed by C2 symmetric chiral selenide-bearing isoborneol skeletons, which were readily prepared from (1S)-10-camphorsulfonic acid, and LiOH promoted the reaction of phenacyl bromide with aldehydes to afford the desired trans oxiranes with up to 62% ee.

The key intermediate octahydroquinazoline ( 1 ) was obtained in one pot synthesis by a modification of the Biginelli reaction. Compound 1 was allowed to react with phenacyl bromide and bromomalononitrile to furnish thiazolo[2,3- b ]quinazoline 3 and 12 , respectively. Interaction of compound 12 with formamide, formic acid and phenyl isothiocyanate yielded the corresponding pyrimidino[4′,5′:4,5]thiazolo[2,3- b ] quinazolines 13 , 14 and 17 , respectively. The structure of the synthesized compounds were elucidated by elemental analyses and spectroscopic analyses. Some of the prepared compounds were tested for their antifungal activity in comparison with tioconazole as a reference fungicide.

Phenacyl bromides undergo smooth vic-diallylation and dipropargylation with allyl and propargyl indium reagents generated in situ from metallic indium and allyl or propargyl bromide to produce 4-arylocta-1,7-dien-4-ol derivatives in good yields. Phenacyl chloride and azide also participated effectively in bis-allylation. Similar results are also obtained from in situ generated allyl or propargyl zinc bromide.

α-Chloroacteic acid and phenacyl bromide were used as reagents reacting with 8-hydroxyquinoline to form bridgehead heterocycles. Reaction of these heterocycles with equi-or bis-molar ratios of 2-(or 4-)methyl substituted heterocyclic quaternary salts afforded a series of monomethine and bismonomethine cyanine dyes. The electronic spectra of the monomethine cyanine dyes in various solvents are discussed. ©

Compounds incorporating 1,3-oxathiole moieties in their frameworks are biologically active. Active methylene ketones can be easily converted to the corresponding dithiocarboxylates by treatment with trithiocarbonate in the presence of sodium hydride. The reactions of aroyl dithiocarboxylates with α-haloketones such as phenacyl bromide or bromoacetone afford substituted 2-ylidene-1,3-oxathioles in good yields.

The crystal structure of acidic phospholipase A 2 (APLA 2 ) from Agkistrodon halys pallas covalently modified by p -bromo-phenacyl-bromide ( p BPB) was determined to a resolution of 2.0 A by an isomorphous difference Fourier method with the native APLA 2 structure as an initial model and refined to a crystallographic R factor of 15.3%. The modified APLA 2 structure is remarkably similar to that of the native one. Least-squares superposition of C α atoms of native and modified APLA 2 results in a root-mean-square coordinate deviation of 0.243 A. The p -bromo-phenacyl group near the active site occupies a position similar to that in p BPB modified bovine pancreatic PLA 2 . The inhibitor covalently bound to the ND1 atom of His48 fits well in the hydrophobic channel, forming extensive hydrophobic interactions with the surrounding residues, especially with the side chains of Phe5 and Cys45 and the main chain of Gly30. However, the inhibitor does not change the conformation of these residues except that Trp31 at the entrance of the hydrophobic channel moves slightly toward the inhibitor. Compared with native APLA 2 , the Ca 2+ -binding loop shows a little conformational change and a cation, probably Na + , occupies in the position of Ca 2+ . The binding of p BPB to APLA 2 induce no other significant conformational changes in the enzyme molecule elsewhere.

A convenient method for the synthesis of thiazoles and aminothiazoles by treatment of phenacyl bromides with thioamides/thiourea in the presence of ammonium-12-molybdophosphate at room temperature has been developed. The products are formed rapidly (within 20 min) and in excellent yields.

This paper deals with the determination of branched carbon number distribution of polyacrylate by liquid chromatography after hydrolyzing the polyacrylate in basic alcohol solution. The products of hydrolysis are alcohols which can be separated by hot methanol. The long chain alcohols are oxidized in potassium permanganate and sulfuric acid. The long chain fatty acids thus obtained are derivatized by phenacyl bromide in triethylamine solution. The derivatives were determined by liquid chromatography.

A simple and practical procedure for the aqueous phase preparation of thiazoles and aminothiazoles has been developed from phenacyl bromides and thioamide/thiourea in the presence of β-cyclodextrin.