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Organic Chemistry International
Number of Followers: 8

This is an Open Access Journal

Open Access journal
ISSN (Print) 2090-200X - ISSN (Online) 2090-2018
Published by Hindawi

[340 journals]

Synthesis and Antiproliferative Activity of Some Quinoline and Oxadiazole
Derivatives
- Abstract: In continuance of our search for newer antiproliferative agents we report herein the synthesis and antiproliferative studies of two series (5a–j and 10a–c) of heterocyclic compounds. All the new compounds were characterized by IR, NMR, and mass spectral data. The antiproliferative activity of 10 compounds (5a–j) was carried out on HeLa (cervix cancer cell line) and MDA-MB-435 (melanoma) and LC50, TGI, and GI50 were calculated, while the antiproliferative activity of 3 compounds (10a–c) was carried out against nine different panels of nearly 60 cell lines (NCI-60) according to the National Cancer Institute (NCI US) Protocol at 10 μM. 1-(7-Hydroxy-4-methyl-2-oxoquinolin-1(2H)-yl)-3-(4-methoxylphenyl)urea (5j) was found to have antiproliferative activity with GI50 of 35.1 μM against HeLa (cervix cancer cell line) and 60.4 μM against MDA-MB-435 (melanoma), respectively. The compounds 10a, 10b, and 10c showed antiproliferative activity with comparatively higher selectivity towards HOP-92 (Non-Small Cell Lung Cancer) with percent growth inhibitions (GIs) of 34.14, 35.29, and 31.59, respectively.
  PubDate: Thu, 24 Nov 2016 06:18:22 +000
Synthesis, Structural Elucidation, and Antibacterial Evaluation of Some
New Molecules Derived from Coumarin, 1,3,4-Oxadiazole, and Acetamide
- Abstract: Because of the reported biological activities of coumarin, 1,3,4-oxadiazole, and acetamides, some new compounds incorporating these moieties were synthesized and evaluated for their biological potential against Gram-positive and Gram-negative bacteria. In the present work, 4-chlororesorcinol (1) and ethyl acetoacetate (2) were mixed in a strong acidic medium to synthesize 6-chloro-7-hydroxy-4-methyl-2-oxo-2H-chromene (3) which was subjected to the intermolecular cyclization after consecutive three steps to synthesize 5-(6-chloro-4-methyl-2-oxo-2H-chromen-7-yl)oxy]-1,3,4-oxadiazol-2-thiol (6). A series of acetamoyl electrophiles, 8a–o, were synthesized from aralkyl/alkyl/aryl amines, 7a–o, in an aqueous basic medium. The final compounds, 9a–o, were synthesized by the reaction of compounds 6 and 8a–o in DMF/NaH. The synthesized compounds were structurally elucidated by spectral data analysis of IR, 1H-NMR, and EIMS. The most of the synthesized compounds remained moderate to excellent antibacterial agents. The molecules, 9e, 9j, and 9k, were the most efficient ones against all the five bacterial strains taken into account.
  PubDate: Wed, 07 Sep 2016 14:33:22 +000
Synthesis of New Energetic Materials and Ionic Liquids Derived from
Metronidazole
- Abstract: Simple and efficient synthetic procedures were established for the preparation of new energetic covalent compounds, salts, and protonated ionic liquids based on the readily available antimicrobial agent metronidazole. Some of these materials exhibit the desirable properties of energetic materials and energetic ionic liquids, such as low vapor pressure, low melting point, good chemical and thermal stability, and high energetic content. For each of the relevant compounds prepared, thermal stability was determined by differential scanning calorimetry. Some of these compounds may be considered promising precursors of pharmaceuticals such as antimicrobial, antiparasitic, antifungal, antineoplastic agents, or enzyme inhibitors.
  PubDate: Thu, 14 Jan 2016 11:23:49 +000
Synthesis, Characterization, and Application of
Poly(N,N′-dibromo-N-ethylnaphthyl-2,7-disulfonamide) as an Efficient
Reagent for the Synthesis of 2-Arylbenzimidazole and
2-Aryl-1-arylmethyl-1H-1,3-benzimidazole Derivatives
- Abstract: The condensation of O-phenylenediamine (OPD) with aryl aldehydes is carried out in acetonitrile using poly(N,N′-dibromo-N-ethylnaphthyl-2,7-disulfonamide) (PBNS) as a novel and heterogeneous catalyst. PBNS has some potential advantages which include ease of separation from the reaction mixture by simple filtration, easy preparation, recoverablility, convenience, and stability under normal condition and also is not dangerous as molecular bromine.
  PubDate: Wed, 06 May 2015 08:27:59 +000
Insight into the Willgerodt-Kindler Reaction of ω-Haloacetophenone
Derivatives: Mechanistic Implication
- Abstract: This paper reports efforts aimed at tuning up the synthesis of a compound library centered on the general template 2-amino-1-phenyl-2-thioxoethanone taking the condensation of ω-haloacetophenone, octasulfur, and morpholine as pilot reaction. Considerations about atomic economy were found extremely precious in selecting the best starting halo-reagent. A one-pot practical method based on use of 2-bromo-1-phenylethanone as substrate and N,N-dimethylformamide as solvent can be easily scaled up to gram amounts (72% yield). Based on this synthetic approach, some more specific examples are reported.
  PubDate: Wed, 10 Dec 2014 09:09:15 +000
Microwave-Assisted Synthesis of Some 1,3,4-Oxadiazole Derivatives and
Evaluation of Their Antibacterial and Antifungal Activity
- Abstract: A series of substituted 1,3,4-oxadiazole derivatives (3a–f) and (6a–f) have been synthesized from diphenylacetic acid hydrazide under microwave irradiation in various reaction conditions. The structures of the synthesized compounds were assigned on the basis of elemental analysis, IR, and 1H NMR. These targeted compounds have been tested for their antibacterial and antifungal activities compared to ampicillin and griseofulvin as standard drug. Compounds 3a, 3e, 3f, 6c, 6d, 6e, and 6d exhibited the maximum antibacterial activities while 3b, 3c, 3d, 3e, 6a, 6d, and 6e exhibited the maximum antifungal activities.
  PubDate: Wed, 03 Dec 2014 06:39:27 +000
Synthesis, Characterization, and Evaluation for Antibacterial and
Antifungal Activities of N-Heteroaryl Substituted Benzene Sulphonamides
- Abstract: The synthesis and biological activity of N-heteroaryl substituted benzene sulphonamides (3a–h) were successful. Simple condensation reaction of benzene sulphonyl chloride (1) with substituted heteroaromatic compounds (2a–h) under dry pyridine and acetone gave the target molecules (3a–h) in good to excellent yield. The compounds were characterized using FTIR, 1HNMR, and 13CNMR. The compounds were screened for antibacterial activity against E. coli, Salmonella typhi, P. aeruginosa, B. cereus, K. pneumonia, and Sarcina lutea and antifungal activity against C. albicans and A. niger. The results of the antimicrobial activity showed improved biological activity against some tested organisms.
  PubDate: Thu, 27 Nov 2014 00:10:05 +000
Proline Based Chiral Ionic Liquids for Enantioselective Michael Reaction
- Abstract: Chiral ionic liquids, starting from (S)-proline, have been prepared and evaluated the ability of a chiral catalyst. In Michael reaction of trans-β-nitrostyrene and cyclohexanone, all the reactions were carried out under homogeneous conditions without any solvent except for excess cyclohexanone. The chiral ionic liquid catalyst with the positive charge delocalized bulky pyrrolidinium cation shows excellent yields (up to 92%), diastereoselectivities (syn/anti = 96/4), and enantioselectivities (up to 95% ee) and could be reused at least three times without any loss of its catalytic activity. Such results demonstrated a promising new approach for green and economic chiral synthesis by using the chiral ionic liquids as a chiral catalyst and a chiral medium.
  PubDate: Thu, 20 Nov 2014 07:14:09 +000
An Efficient, Clean, and Catalyst-Free Synthesis of Fused Pyrimidines
Using Sonochemistry
- Abstract: In this report, synthesis of indenopyrido[2,3-d]pyrimidine and pyrimido[4,5-b]quinoline derivatives was investigated via one-pot three-component reaction between 6-amino-2-(alkylthio)-pyrimidin-4(3H)one, 1,3-indanedione, or 1,3-cyclohexadione and arylaldehyde under ultrasonic irradiation in ethylene glycol as solvent at 65°C. In these reactions fused pyrimidine derivatives were synthesized with high to excellent yields (82–97%) and short reaction times (10–33 min).
  PubDate: Sun, 16 Nov 2014 09:11:09 +000
An Ultrasound Mediated Green Synthesis of
Benzimidazolylthiounsaturatednitriles Using Water as a Green Solvent
- Abstract: Reaction of 2-cyanothiomethylbenzimidazole 1 with an aromatic aldehydes in water under ultrasonic irradiation for 10–13 min gave the corresponding unsaturated nitriles 2a–h which is an efficient and simple method under green conditions. The unsaturated nitrile derivatives were obtained in 86–98% yield with a short reaction time without any tedious workup procedures.
  PubDate: Sun, 09 Nov 2014 07:55:39 +000
Stereoselective Synthesis of (+)--Conhydrine from R-(+)-Glyceraldehyde
- Abstract: Stereoselective synthesis of (+)-α-Conhydrine was accomplished from protected (R)-(+)-glyceraldehyde, a familiar carbohydrate predecessor. Our synthetic strategy featured the following two key reactions. One is Zn-mediated stereoselective aza-Barbier reaction of imine 6 with allyl bromide to afford chiral homoallylic amine 7, and the other is ring-closing metathesis.
  PubDate: Mon, 20 Oct 2014 06:28:25 +000
Water Mediated Synthesis of
N′-Arylmethylene-4,5,6,7-tetrahydro-2H-indazole-3-carbohydrazide Library
- Abstract: A novel two-step synthesis of 4,5,6,7-tetrahydro-2H-indazole-3-carbohydrazide has been developed. The library of N′-arylmethylene-4,5,6,7-tetrahydro-2H-indazole-3-carbohydrazide was generated by coupling of hydrazide to various aromatic and heterocyclic aldehydes in water media at ambient temperature with great flexibility regarding reaction time and yield.
  PubDate: Wed, 15 Oct 2014 11:41:54 +000
Microwave-Assisted Three-Component “Catalyst and Solvent-Free” Green
Protocol: A Highly Efficient and Clean One-Pot Synthesis of
Tetrahydrobenzo[b]pyrans
- Abstract: A green and highly efficient method has been developed for the one-pot synthesis of tetrahydrobenzo[b]pyrans via a three-component condensation of aldehydes, 1,3-cyclic diketones, and malononitrile under MW irradiation without using any catalyst and solvent. This transformation presumably occurs by a sequential Knoevenagel condensation, Michael addition, and intramolecular cyclization. Operational simplicity, solvent and catalyst-free conditions, the compatibility with various functional groups, nonchromatographic purification technique, and high yields are the notable advantages of this procedure.
  PubDate: Wed, 17 Sep 2014 12:26:34 +000
A Novel Regiospecific Synthesis of 1-Chloro-2-arylcyclohexenes
- Abstract: An efficient high yielding chemoselective synthesis of eleven novel 1-chloro-2-arylcyclohexenes employing the Suzuki cross coupling of 1-bromo-2-chlorocyclohexene with eleven different aryl boronic acids and Pd(dppf) catalyst is reported.
  PubDate: Thu, 10 Jul 2014 11:33:12 +000
Kinetic and Mechanistic Investigation of Pyrano[2,3-d]pyrimidine Formation
in the Presence of Catalyst under Novel One-Pot Three-Component Reaction
- Abstract: Sodium acetate was applied as an efficient catalyst for the one-pot, three-component condensation reactions consisting of 4-nitrobenzaldehyde 2, malononitrile 3, and thiobarbituric acid 1. Use of nontoxic reaction components, short reaction times, environmental, easy work-up, and high yields are some remarkable advantages of this method. Kinetics and mechanism of the reaction were spectrally studied and the second order rate constant (kovr = k1) was automatically calculated by the standard equations contained within the program. The second order rate constant [Ln(kovr = k1), Ln(kovr = k1)/T] that depended on reciprocal temperature was in good agreement with the Arrhenius and Eyring equations, respectively. This data provided the suitable plots for calculating the activation energy and parameters (Ea, ΔG‡, ΔS‡, and ΔH‡) of the reaction. Furthermore, from studying the effects of solvent, concentration, and catalyst on the reaction rate, useful information was obtained regarding the mechanism. The results showed that the first step of the reaction mechanism is a rate determining step (RDS). The proposed mechanism was confirmed in accordance with the experimental data and also the steady state approximation.
  PubDate: Sun, 11 May 2014 12:18:59 +000
Synthesis of Ibuprofen Using Silica-Supported Preyssler Nanoparticles as
an Eco-Friendly, Inexpensive, and Efficient Catalyst
- Abstract: This paper describes an alternative and simple procedure for the synthesis of Ibuprofen using Silica-Supported Preyssler Nanoparticles (H14[NaP5W30O110]/SiO2) (SPNPs), as an eco-friendly, inexpensive, and efficient catalyst. High yields, simplicity of operation, and easy work-up procedure are some advantages of this protocol. Silica-Supported Preyssler Nanoparticles (H14[NaP5W30O110]/SiO2) (SPNPs) offer the advantages of a higher hydrolytic and thermal stability. The salient features of Preyssler’s anion are availability, nontoxicity and reusability. We believe this methodology can find usefulness in organic synthesis.
  PubDate: Tue, 06 May 2014 07:27:42 +000
Synthesis of Novel Symmetrical and Unsymmetrical o-Phthalic Acid Diamides
- Abstract: Phthalic anhydride was treated with secondary amines in acetic acid yielding 2-(diethyl (or) 4-alkylpiperazine or morpholine-1-carbonyl) benzoic acids. The latter were reacted, again, with secondary amines and arylamines by using the coupling reagent HATU and Et3N as a base in DMF giving the novel symmetrical o-phthalic acid diamides , unsymmetrical o-phthalic acid diamides , and primary amidic-secondary amidic containing unsymmetrical o-phthalic acid diamides , respectively.
  PubDate: Mon, 05 May 2014 00:00:00 +000
Glycerol Containing Triacetylborate Mediated Syntheses of Novel
2-Heterostyryl Benzimidazole Derivatives: A Green Approach
- Abstract: A very simple, mild, efficient, and novel green methodology has been developed for the syntheses of some 2-hetero/styryl-benzimidazoles. Title compounds were synthesized by the condensation of -phenylenediamine with cinnamic acids at 150–180°C for 5-6 h using glycerol containing triacetylborate (10–20 mol%) as the reaction medium. In an alternative approach, condensation of 2-methylbenzimidazole derivatives with aromatic aldehydes was done using glycerol containing triacetylborate (10–20 mol%) as the reaction medium.
  PubDate: Sun, 27 Apr 2014 08:20:57 +000
Synthesis and Antimicrobial Activities of
N-(Heteroaryl-substituted)-p-toluenesulphonamides
- Abstract: A new class of N-(heteroaryl-substituted)-p-toluenesulphonamides has been synthesized exhibiting antibacterial and antifungal properties. The condensation reaction of p-toluenesulphonyl chloride 1 with appropriate substituted amino pyridines 2a–g in acetone furnished N-(heteroaryl-substituted)-p-toluenesulphonamides 3a–g. These derivatives were characterized by IR, 1H-, and 13C-NMR spectroscopy and were screened in vitro against gram-positive bacteria, gram-negative bacteria, and fungi organisms using agar-diffusion method. Results indicated improved biological activities over reference drugs such as Tetracycline (TCN) and Fluconazole (FLU).
  PubDate: Tue, 15 Apr 2014 08:13:37 +000
An Efficient Method for Synthesis of N-tert-Butyl Amides Using Oxalic Acid
Dihydrate in Solvent-Free Condition
- Abstract: An efficient method for the synthesis of N-tert-butyl amides by reaction of nitriles with tert-butyl acetate or tert-butanol is described using oxalic acid dihydrate in solvent-free condition. The result showed that tert-butyl acetate served as a relatively better source of tert-butyl carbocation than tert-butanol.
  PubDate: Tue, 08 Apr 2014 07:04:06 +000
Synthesis and Biological Evaluation of
4-(3-Hydroxy-benzofuran-2-yl)coumarins
- Abstract: Various 4-bromomethylcoumarins (1a-k) were reacted with methyl salicylate to yield 2-(2-oxo-2H-chromen-4-ylmethoxy)-benzoic acid methyl esters (2a-k). Formations of (3a-k) were achieved by using DBU under microwave irradiation. Structures of all the compounds were established on the basis of their spectral data. All the compounds were tested in vitro for their antimicrobial activity and cell cytotoxicity. All the tested compounds (2b-k) and (3a-k) were shown to be better activity against Staphylococcus aureus than the standard Ciprofloxacin. The compound (3k) (R = 6-OMe) was found to be more potent cytotoxic than the standard 5-fluorouracil.
  PubDate: Thu, 27 Mar 2014 08:25:33 +000
Microwave Assisted Solvent-Free Synthesis of Some Imine Derivatives
- Abstract: Some imine derivatives (1a–7d) were synthesized using a rapid and an environmentally friendly method with reaction of aromatic aldehydes (a–d) and aromatic amines (1–7) (in 1 : 1 molar ratio) in the presence of -ethoxyethanol as a wetting reagent (2 drops) under solvent-free conditions using microwave heating.
  PubDate: Wed, 26 Mar 2014 12:00:46 +000
Synthesis of N-Alkyl-2-thiomethyl Benzimidazoles: A Green Approach
- Abstract: A green approach for the synthesis of N-alkyl-2-thiomethyl benzimidazoles 2 (R=CH3, C2H5, CH2Ph) under different conditions has been developed from N-alkyl-2-chloromethyl benzimidazole (i.e., CH3, C2H5, CH2Ph) 1 by reaction with thiourea by physical grinding, or by using green solvents like ethanol and PEG-600, or by using microwave irradiation technique.
  PubDate: Mon, 17 Mar 2014 13:06:20 +000
An Efficient One-Pot Multi-Component Synthesis of
3,4-Dihydropyrimidin-2-(1H)-Ones/Thiones Catalyzed by Bismuth (III)
Sulfate Trihydrate under Solvent-Free Conditions
- Abstract: A convenient and efficient protocol for the one-pot synthesis of 3,4-dihydropyrimidin-2-(1H)-one/thione derivatives of aldehydes, and 1,3-dicarbonyl compounds with Bismuth (III) sulfate trihydrate as the catalyst was described. We had the advantages of good performance, simplicity, and short time reaction under solvent-free conditions. The catalyst can be repeatedly reused without loss of its activity.
  PubDate: Thu, 13 Mar 2014 00:00:00 +000
Catalytic Synthesis of -Aminonitriles Using Nano Copper Ferrite under
Green Conditions
- Abstract: Copper ferrite nanomaterial as reusable heterogeneous initiator in the synthesis of α-aminonitriles. The nanocatalyst is easily recovered and its reusability is recorded. Synthesis of α-aminonitriles derivatives by one-pot reaction of different aldehydes with amines and trimethylsilyl cyanides has been developed using nano copper ferrite catalyst under room temperature and green solvent (water as solvent) conditions. α-aminonitriles are important in preparing a wide variety of amino acids, amides, diamines, and nitrogen containing heterocycles.
  PubDate: Wed, 12 Mar 2014 15:39:38 +000
One-Pot Synthesis of Metallopyrazinoporphyrazines Using
2,3-Diaminomaleonitrile and 1,2-Dicarbonyl Compounds Accelerated by
Microwave Irradiation
- Abstract: A one-pot microwave-assisted synthesis of metallopyrazinoporphyrazines as porphyrazine derivatives carrying six-membered pyrazine rings annulated at the periphery of the tetrapyrrolic macrocycle is described starting from 2,3-diaminomaleonitrile, 1,2-dicarbonyl compounds, metal salts, and urea.
  PubDate: Thu, 27 Feb 2014 13:20:32 +000
In Quest of “Stereoselective Switch” for On-Water Hydrothiolation of
Terminal Alkynes Using Different Additives and Green Synthesis of Vicinal
Dithioethers
- Abstract: On-water hydrothiolation reaction between terminal alkyne and thiol has been probed in the presence of various additives. Aromatic alkynes yield corresponding 1-alkenyl sulfides, whereas aliphatic alkynes undergo double-addition yielding vicinal disulfides in good to excellent yields. Formation of 1-alkenyl sulfides proceeds with a high degree of regioselectivity (via anti-Markovnikov addition), and switching the stereoselectivity between E/Z isomers has been noticeably realized in the presence of different additives/promoters.
  PubDate: Thu, 13 Feb 2014 16:02:51 +000
Green Chemistry: New Synthesis of Substituted Chromenes and Benzochromenes
via Three-Component Reaction Utilizing Rochelle Salt as Novel Green
Catalyst
- Abstract: Substituted 2-amino-4-aryl-7-hydroxy-4H-chromene-3-carbonitriles (6), 2-amino-4-aryl-4H-benzo[h]chromene-3-carbonitriles (7), and 3-amino-1-aryl-1H-benzo[f]chromenes-2-carbonitriles (8) were prepared, in good yields, via one-pot three-component reactions of aromatic aldehydes (1), malononitrile (2), and resorcinol (3) or α-naphthol (4) or β-naphthol (5) in refluxing ethanol or water in the presence of Rochelle salt as novel green heterogeneous and reusable catalyst.
  PubDate: Thu, 30 Jan 2014 09:17:51 +000
An Efficient and Green Method for Synthesis of 2,4,5-Triarylimidazoles
without Use of Any Solvent, Catalyst, or Solid Surface
- Abstract: An efficient and green method for synthesis of 2,4,5-triarylimidazoles without use of any catalyst or solvent has been developed simply by heating (at 130°C) of mixtures of 1,2-diketone, aromatic aldehyde, and ammonium acetate in 1 : 1 : 3 mole ratio.
  PubDate: Tue, 10 Dec 2013 11:23:55 +000
Synthesis of Pyrazine Substituted 1,3,4-Thiadiazole Derivatives and Their
Anticonvulsant Activity
- Abstract: The synthesis of new pyrazine substituted 1,3,4-thiadiazole derivatives was carried out in good yield by the reaction of pyrazine substituted 1,3,4-thiadiazoles with various sulfonyl chlorides. A chemical structure of all the new compounds was confirmed by 1H NMR and mass spectral data. The new compounds were screened for their anticonvulsant activity against maximal electroshock (MES) seizure method. Rotarod method was employed to determine the neurotoxicity. Few compounds showed significant changes in anticonvulsant activity. The same compounds showed no neurotoxicity at the maximum dose administered (100 mg/kg).
  PubDate: Wed, 04 Dec 2013 10:14:46 +000