Pharmaceutical Sciences and Natural Products - Research Publications

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Augmented anticancer efficacy of doxorubicin-loaded polymeric nanoparticles after oral administration in a breast cancer induced animal model
(2011) Jain, A.K.; Swarnakar, N.K.; Das, M.; Godugu, C.; Singh, R.P.; Rao, P.R.; Jain, S.
The present investigation reports an extensive evaluation of in vitro and in vivo anticancer efficacy of orally administered doxorubicin-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (Dox-NPs) in a breast cancer induced animal model. Spherically shaped Dox-NPs were prepared with an entrapment efficiency and particle size of 55.40 ? 2.30% and 160.20 ? 0.99 nm, respectively, and freeze-dried with 5% trehalose using stepwise freeze-drying. Cytotoxicity, as investigated on C127I cell line, revealed insignificant differences between the IC 50 of free Dox and Dox-NPs treated cells in the first 24 h, while higher cytotoxicity was demonstrated by Dox-NPs, following 72 h of incubation. Confocal laser scanning microscopy (CLSM) imaging corroborated that nanoparticles were efficiently localized into the nuclear region of C127I cells. The cellular uptake profile of Dox-NPs revealed both time and concentration dependent increases in the Caco-2 cell uptake as compared to the free Dox solution. Further, Dox-NPs significantly suppressed the growth of breast tumor in female Sprague-Dawley (SD) rats upon oral administration. Finally, orally administered Dox-NPs showed a marked reduction in cardiotoxicity when compared with intravenously injected free Dox as also evident by the increased level of malondialdehyde (MDA), lactate dehydrogenase (LDH), and creatine phosphokinase (CK-MB) and reduced levels of glutathione (GSH) and superoxide dismutase (SOD). The reduced cardiotoxicity of orally administered Dox-NPs was also confirmed by the major histopathological changes in the heart tissue after the treatments of intravenously injected free Dox and orally delivered Dox-NPs. ? 2011 American Chemical Society.
Intracellular delivery of redox cycler-doxorubicin to the mitochondria of cancer cell by folate receptor targeted mitocancerotropic liposomes
(2012) Malhi, Sarandeep Singh; Budhiraja, Abhishek; Arora, Sumit; Chaudhari, Kiran R.; Nepali, Kunal; Kumar, Raj; Sohi, Harmik; Murthy, Rayasa S.R.
Cancer cells reflect higher level of ROS in comparison to the normal cell, so they become more vulnerable to further oxidative stress induced by exogenous ROS-generating agents. Through this a novel therapeutic strategy has evolved, which involves the delivery of redox cycler-doxorubicin (DOX) to the mitochondria of cancer cell where it acts as a source of exogenous ROS production. The purpose of this study is to develop a liposomal preparation which exhibits a propensity to selectively target cancer cell along with the potential of delivering drug to mitochondria of cell. We have rendered liposomes mitocancerotropic (FA-MTLs) by their surface modification with dual ligands, folic acid (FA) for cancer cell targeting and triphenylphosphonium (TPP) cations for mitochondria targeting. The cytotoxicity, ROS production and cell uptake of doxorubicin loaded liposomes were evaluated in FR (+) KB cells and found to be increased considerably with FA-MTLs in comparison to folic acid appended, mitochondria targeted and non-targeted liposomes. As confirmed by confocal microscopy, the STPP appended liposomes delivered DOX to mitochondria of cancer cell and also showed higher ROS production and cytotoxicity in comparison to folic acid appended and non-targeted liposomes. Most importantly, mitocancerotropic liposomes showed superior activity over mitochondria targeted liposomes which confirm the synergistic effect imparted by the presence of dual ligands - folic acid and TPP on the enhancement of cellular and mitochondrial delivery of doxorubicin in KB cells. ? 2012 Elsevier B.V. All rights reserved.
Cellular uptake, intracellular trafficking and cytotoxicity of silver nanoparticles
(2012) Singh, R.P.; Ramarao, P.
Silver nanoparticles (Ag NPs) are used in consumer products and wound dressings due to their antimicrobial properties. However, in addition to toxic effects on microbes, Ag NPs can also induce stress responses as well as cytotoxicity in mammalian cells. We observed that Ag NPs are efficiently internalized via scavenger receptor-mediated phagocytosis in murine macrophages. Confocal and electron microscopy analysis revealed that internalized Ag NPs localize in the cytoplasm. Ag NPs cause mitochondrial damage, induce apoptosis and cell death. These effects were abrogated in presence of Ag ion-reactive, thiol-containing compounds suggesting the central of Ag ions in Ag NP toxicity. Quantitative image analysis revealed that intracellular dissolution of Ag NPs occurs about 50 times faster than in water. In conclusion, we demonstrate for the first time that Ag NPs are internalized by scavenger receptors, trafficked to cytoplasm and induce toxicity by releasing Ag ions. ? 2012 Elsevier Ireland Ltd.
Surfactant-assisted dispersion of carbon nanotubes: Mechanism of stabilization and biocompatibility of the surfactant
(2013) Singh, R.P.; Jain, S.; Ramarao, P.
Nanoparticles (NPs) are thermodynamically unstable system and tend to aggregate to reduce free energy. The aggregation property of NPs results in inhomogeneous exposure of cells to NPs resulting in variable cellular responses. Several types of surfactants are used to stabilize NP dispersions and obtain homogenous dispersions. However, the effects of these surfactants, per se, on cellular responses are not completely known. The present study investigated the application of Pluronic F68 (PF68) for obtaining stable dispersion of NPs using carbon nanotubes as model NPs. PF68-stabilized NP suspensions are stable for long durations and do not show signs of aggregation or settling during storage or after autoclaving. The polyethylene oxide blocks in PF68 provide steric hindrance between adjacent NPs leading to stable NP dispersions. Further, PF68 is biocompatible in nature and does not affect integrity of mitochondria, lysosomes, DNA, and nuclei. Also, PF68 neither induce free radical or cytokine production nor does it interfere with cellular uptake mechanisms. The results of the present study suggest that PF68-assisted dispersion of NPs produced suspensions, which are stable after autoclaving. Further, PF68 does not interfere with normal physiological functions suggesting its application in nanomedicine and nanotoxicity evaluation. ? 2013 Springer Science+Business Media Dordrecht.
Accumulated polymer degradation products as effector molecules in cytotoxicity of polymeric nanoparticles
(2013) Singh, R.P.; Ramarao, P.
Polymeric nanoparticles (PNPs) are a promising platform for drug, gene, and vaccine delivery. Although generally regarded as safe, the toxicity of PNPs is not well documented. The present study investigated in vitro toxicity of poly-?-caprolactone, poly(DL-lactic acid), poly(lactide-cocaprolactone), and poly(lactide-co-glycide) NPs and possible mechanism of toxicity. The concentration-dependent effect of PNPs on cell viability was determined in a macrophage (RAW 264.7), hepatocyte (Hep G2), lung epithelial (A549), kidney epithelial (A498), and neuronal (Neuro 2A) cell lines. PNPs show toxicity at high concentrations in all cell lines. PNPs were efficiently internalized by RAW 264.7 cells and stimulated reactive oxygen species and tumor necrosis factor-alpha production. However, reactive nitrogen species and interleukin-6 production as well as lysosomal and mitochondrial stability remained unaffected. The intracellular degradation of PNPs was determined by monitoring changes in osmolality of culture medium and a novel fluorescence recovery after quenching assay. Cell death showed a good correlation with osmolality of culture medium suggesting the role of increased osmolality in cell death. ? The Author 2013. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved.
Recent advancements in small molecule inhibitors of insulin-like growth factor-1 receptor (IGF-1R) tyrosine kinase as anticancer agents
(2013) Negi, A.; Ramarao, P.; Kumar, R.
Advancements in understanding of the genetics, genomics, biochemistry and the pharmacology of cancer in human, have driven the current cancer chemotherapy to intently focus on development of target-based approaches rather than conventional approaches. From among the various targets identified, validated and inhibited at different hallmarks of cancer, protein tyrosine kinases (PTKs) have been exploited the most. Insulin receptors (IRs), insulin like growth factor receptors (IGF-1R) and their hybrid receptors belong to tyrosine kinase receptor (TKR) family, constitute a structural homology among them and generate a growth promoting IGF system on binding with either insulin, IGF-1 or IGF-2. The system induces the mitogenic effects through a torrent of cell signals produced as a result of cross talk with other growth promoting peptides and steroidal hormones, ultimately resulting in hijacking apoptosis and increasing cell proliferation and cell survival in cancer cells. Various strategies such as anti-IGF-1R antibodies, IGF-1 mimetic peptides, antisense strategies, IGF-1R specific peptide aptamers, targeted degradation of IGF-1R and expression of dominant negative IGF-1R mutants have been explored to inhibit the IGF-1R signaling. However, targeting IGF-1R with small molecules has gained considerable attention in last few years due to their ease of synthesis, ease of optimization of absorption, distribution, metabolism, excretion and toxicity (ADMET) parameters, oral route of administration, lesser side effects and cost effectiveness. The present review provides a broad overview and discusses the highlights on discoveries, SAR studies and binding interactions of small molecules with either IGF-1R active or allosteric sites reported till date. ? 2013 Bentham Science Publishers.
In-vitro anti-mutagenic activity of Asparagus racemosus: An ayurvedic medicinal plant
(Academic Journals Inc., 2013) Singh, Ramit; Kaur, Rajbir; Arora, Saroj; Jaitak, Vikas
Asparagus racemosus is a plant traditionaly used in epilepsy, as a brain tonic, cardiac disorders, hypertension, habitual abortions, weakness of the uterus, excessive bleeding during menstruation. The current study evaluated the antimutagenic pottential of methanolic (RME) and aqueous methanolic extract (RAE) extracted from A. racemosus. Ames assay was used to acess the antimutagenic potential of RME and RAE (2.5x103, 1.0x103, 0.5x103, 0.25x103, 0.10x103 and 0.01x103 ?g 0.1 mL plate-1) that was added with mutagenic activation of TA98 and TA100 strain of Salmonella typhimurium. A. racemosus extract RME and RAE have been found to have effective in the inhibition of mutation induced by NPD and sodium azide. Among the two extracts, RAE showed maximum inhibition of 49.2% followed by RME having inhibition of 40.63% in Co-incubation mode. Current study indicated that A. racemosus can be used as a new source of anti-mutagenic. ? 2013 Academic Journals Inc.
Recent Advancements in Small Molecule Inhibitors of Insulin–like Growth Factor-1 Receptor (IGF-1R) Tyrosine Kinase as Anticancer agents
(Bentham Science, 2013) Negi, Arvind; Ramarao, P.; Kumar, Raj
Advancements in understanding of the genetics, genomics, biochemistry and the pharmacology of cancer in human, have driven the current cancer chemotherapy to intently focus on development of target-based approaches rather than conventional approaches. From among the various targets identified, validated and inhibited at different hallmarks of cancer, protein tyrosine kinases (PTKs) have been exploited the most. Insulin receptors (IRs), insulin like growth factor receptors (IGF-1R) and their hybrid receptors belong to tyrosine kinase receptor (TKR) family, constitute a structural homology among them and generate a growth promoting IGF system on binding with either insulin, IGF-1 or IGF-2. The system induces the mitogenic effects through a torrent of cell signals produced as a result of cross talk with other growth promoting peptides and steroidal hormones, ultimately resulting in hijacking apoptosis and increasing cell proliferation and cell survival in cancer cells. Various strategies such as anti-IGF-1R antibodies, IGF-1 mimetic peptides, antisense strategies, IGF-1R specific peptide aptamers, targeted degradation of IGF-1R and expression of dominant negative IGF- 1R mutants have been explored to inhibit the IGF-1R signaling. However, targeting IGF-1R with small molecules has gained considerable attention in last few years due to their ease of synthesis, ease of optimization of absorption, distribution, metabolism, excretion and toxicity (ADMET) parameters, oral route of administration, lesser side effects and cost effectiveness. The present review provides a broad overview and discusses the highlights on discoveries, SAR studies and binding interactions of small molecules with either IGF-1R active or allosteric sites reported till date.
Anticancer activity of essential oils: A review
(2013) Bhalla, Yashika; Gupta, Vinay Kumar; Jaitak, Vikas
Natural essential oil constituents play an important role in cancer prevention and treatment. Essential oil constituents from aromatic herbs and dietary plants include monoterpenes, sesquiterpenes, oxygenated monoterpenes, oxygenated sesquiterpenes and phenolics among others. Various mechanisms such antioxidant, antimutagenic and antiproliferative, enhancement of immune function and surveillance, enzyme induction and enhancing detoxification, modulation of multidrug resistance and synergistic mechanism of volatile constituents are responsible for their chemopreventive properties. This review covers the most recent literature to summarize structural categories and molecular anticancer mechanisms of constituents from aromatic herbs and dietary plants. ? 2013 Society of Chemical Industry.
Cystathionine β-Lyase-Like Protein with Pyridoxal Binding Domain Characterized in Leishmania major by Comparative Sequence Analysis and Homology Modelling
(Hindawi, 2013) Negi, Arvind; Bhushan, Satej; Gupta, Pawan; Garg, Prabha; Kumar, Raj
Cystathionine β-lyase-like protein (CBLP), one of the key enzymes involved in methionine biosynthesis utilising pyridoxal phosphate (PLP) as a cofactor, has recently been reported in Leishmania major. Its presence in the parasite and absence in humans warrant its full characterisation and fruition as a potent, selective, and inevitable druggable target. Due to the unavailability of X-ray 3D structure of CBLP, a homology model for this protein was developed for the first time. The model was evaluated for PLP binding site and various conserve domain residues of the protein recommended by comparative sequence analyses by different protein analysis tools. The model was validated and discovered to be robust and statistically significant. The final model was superimposed on template of Arabidopsis thaliana (PDB ID: 1IBJ) and RMSD was found to be 0.486. The PLP binding site residues of both the proteins were ensued to be highly conserved indicated by Gly71, Met72, Tyr95, Asp169, and Ser193 as well as formation of aldimine bond with Lys194. This was further verified through molecular simulation of PLP into the cofactor binding site of the modelled protein. The present study may therefore play a directing role in the designing of novel, potential, and selective antileishmanial agents.
Medicinal attributes of pyrazolo[3,4-d]pyrimidines: A review
(2013) Chauhan, Monika; Kumar, Raj
Pyrazolopyrimidines are the fused heterocyclic ring systems which structurally resemble purines which prompted biological investigations to assess their potential therapeutic significance. They are known to play a crucial role in numerous disease conditions. The advent of their first bioactivity as adenosine antagonistic property divulged their medicinal potential. Radioactivity test on mice cells, morphometric and serological tests on rat hepatocytes, antitumor testing against L1210 and P388 leukemias in mice threw light on their biophysical aspects of significance. Biochemical properties were explored via xanthine oxidase assay, antioxidant enzyme assays, Western blot analysis, mRNA expression of apoptopic genes, receptor binding assays, and tryptan blue exclusion cytotoxicity evaluation. The collective results of biochemical and biophysical properties foregrounded their medicinal significance in central nervous system, cardiovascular system, cancer, inflammation etc. The present manuscript to the best of our knowledge is the first compilation on synthesis and medicinal aspects including structure-activity relationships of pyrazolo[3,4-d]pyrimidines reported to date. ? 2013 Elsevier Ltd. All rights reserved.
1-Acetyl-3,5-diaryl-4,5-dihydro(1H)pyrazoles: Exhibiting anticancer activity through intracellular ROS scavenging and the mitochondria-dependent death pathway
(Wiley-VCH Verlag, 2014) Alex, Jimi M.; Singh, Sandeep; Kumar, Raj
A series of 17 analogs of 1-acetyl-4,5-dihydro(1H)pyrazoles (JP-1 to JP-17) bearing two aromatic rings at positions 3 and 5, either of which ought to be heterocyclic, were synthesized and evaluated for their anti-proliferative potential against breast cancer (MCF-7 and T-47D) and lung cancer (H-460 and A-549) cell lines for the first time. JP-1-7, -10, -11, -14, and -15 were observed to exhibit significant anti-proliferative activity against MCF-7 cells. Some notions about structure-activity relationships are reported. The investigated compounds were found to lower the intracellular reactive oxygen species in the H2DCFDA assay and also caused mitochondria-dependent cell death in the MCF-7 cell line, indicating a plausible mechanism of their anticancer effect. Analogs of 1-acetyl-4,5-dihydro(1H)pyrazoles (JP-1-17) were synthesized and evaluated for their anti-proliferative activity in four cancer cell lines and for their intracellular ROS scavenging properties. An attempt was made to determine the mitochondrial membrane potential of MCF-7 cells treated with JP-1 and -14, aiming to elucidate the mechanism by which proliferation was curbed. ? 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
4,5-Dihydro-1H-pyrazole: An indispensable scaffold
(Informa Healthcare, 2014) Alex, Jimi Marin; Kumar, Raj
Pyrazoles, categorized as nitrogen-containing heterocycles, are well known for their interminable participation in the field of perpetual research and development of therapeutical active agents. As a consequence pyrazoles became an inevitable core of numerous drugs having diverse activities. The broad spectrum of activities portrayed by the pyrazoles instigated the researchers to modify the pyrazole ring as 4,5-dihydro-1H-pyrazoles commonly known as 2-pyrazolines. The present review is a concerted effort to retrace compounds covered from 2009-till date which owe diverse biological activities to the 2-pyrazoline scaffold and also condenses the retro-synthetic approaches employed for their synthesis. This endeavor culminated in revelation that inhibitory potential varied when the substituents in particular N-substituents of 2-pyrazolines were altered. ? 2014 Informa UK Ltd.
Chemical composition and biological effects of artemisia maritima and artemisia nilagirica essential oils from wild plants of Western Himalaya
(Georg Thieme Verlag, 2014) Stappen, Iris; Wanner, J, rgen; Tabanca, Nurhayat; Wedge, David E.; Ali, Abbas; Khan, Ikhlas A.; Kaul, Vijay K.; Lal, Brij; Jaitak, Vikas; Gochev, Velizar; Girova, Tania; Stoyanova, Albena; Schmidt, Erich; Jirovetz, Leopold; Stappen, I.; Wanner, J.; Tabanca, N.; Wedge, D.E.; Ali, A.; Khan, I.A.; Kaul, V.K.; Lal, B.; Jaitak, V.; Gochev, V.; Girova, T.; Stoyanova, A.; Schmidt, E.; Jirovetz, L.
Artemisia species possess pharmacological properties that are used for medical purposes worldwide. In this paper, the essential oils from the aerial parts of Artemisia nilagirica and Artemisia maritima from the western Indian Himalaya region are described. The main compounds analyzed by simultaneous GC/MS and GC/FID were camphor and 1,8-cineole from A. maritima, and camphor and artemisia ketone from A. nilagirica. Additionally, the oils were evaluated for their antibacterial, antifungal, mosquito biting deterrent, and larvicidal activities. A. nilagirica essential oil demonstrated nonselective antifungal activity against plant pathogens Colletotrichum acutatum, Colletotrichum fragariae, and Colletotrichum gloeosporioides, whereas A. maritima did not show antifungal activity. Both Artemisia spp. exhibited considerable mosquito biting deterrence, whereas only A. nilagirica showed larvicidal activity against Aedes aegypti. Antibacterial effects assessed by an agar dilution assay demonstrated greater activity of A. maritima essential oil against Staphylococcus aureus and Pseudomonas aeruginosa compared to A. nilagirica.
Pyrrolo- and pyridomorphinans: Non-selective opioid antagonists and delta opioid agonists/mu opioid partial agonists
(Elsevier, 2014) Kumar, Vinod; Clark, Mary J.; Traynor, J. R.; Lewis, J. W.; Husbands, Stephen M.
Opioid ligands have found use in a number of therapeutic areas, including for the treatment of pain and opiate addiction (using agonists) and alcohol addiction (using antagonists such as naltrexone and nalmefene). The reaction of imines, derived from the opioid ligands oxymorphone and naltrexone, with Michael acceptors leads to pyridomorphinans with structures similar to known pyrrolo- and indolomorphinans. One of the synthesized compounds, 5e, derived from oxymorphone had substantial agonist activity at delta opioid receptors but not at mu and/or kappa opioid receptors and in that sense profiled as a selective delta opioid receptor agonist. The pyridomorphinans derived from naltrexone and naloxone were all found to be non-selective potent antagonists and as such could have utility as treatments for alcohol abuse.
Chemical composition and biological effects of Artemisia essential oils from Western Himalaya
(Theime, 2014) Stappen, Iris; Wanner, J, rgen; Tabanca, Nurhayat; Wedge, David E.; Ali, Abbas; Khan, Ikhlas A.; Kaul, Vijay K.; Lal, Brij; Jaitak, Vikas; Gochev, Velizar; Girova, Tania; Stoyanova, Albena; Schmidt, Erich; Jirovetz, Leopold
Artemisia species possess pharmacological properties that are used for medical purposes worldwide. In this paper, the essential oils from the aerial parts of Artemisia nilagirica and Artemisia maritima from the western Indian Himalaya region are described. The main compounds analyzed by simultaneous GC/MS and GC/FID were camphor and 1,8-cineole from A. maritima, and camphor and artemisia ketone from A. nilagirica. Additionally, the oils were evaluated for their antibacterial, antifungal, mosquito biting deterrent, and larvicidal activities. A. nilagirica essential oil demonstrated nonselective antifungal activity against plant pathogens Colletotrichum acutatum, Colletotrichum fragariae, and Colletotrichum gloeosporioides, whereas A. maritima did not show antifungal activity. Both Artemisia spp. exhibited considerable mosquito biting deterrence, whereas only A. nilagirica showed larvicidal activity against Aedes aegypti. Antibacterial effects assessed by an agar dilution assay demonstrated greater activity of A. maritima essential oil against Staphylococcus aureus and Pseudomonas aeruginosa compared to A. nilagirica.
Synthesis and xanthine oxidase inhibitory activity of 5,6 dihydropyrazolo/pyrazolo[1,5-c]quinazoline derivatives
(Elsevier, 2014) Kumar, Deependra; Kaur, Gagandeep; Negi, Arvind; Kumar, Sanjeev; Singh, Sandeep; Kumar, Raj
Some 5,6-dihydropyrazolo/pyrazolo[1,5-c]quinazoline derivatives were rationally designed, synthesized and evaluated for in vitro xanthine oxidase inhibitory activity for the first time. Some notions about structure activity relationships are presented. The compounds 6g, 6h and 6e were found to be significantly active against XO. The compound 6g emerged as the most potent XO inhibitor as compared to allopurinol and free radical scavenger. The molecular docking of 6g into the XO active site highlighted its mode of binding and important interactions such as hydrogen bonding, π–π stacking with amino acid residues like Ser876, Thr1010, Phen914, Phe1009 and Phe649 and its close proximity to dioxothiomolybdenum (MOS).
Microwave-assisted synthesis of pyrazolo[1,5-c]quinazolines and their derivatives
(Elsevier, 2014) Kumar, Deependra; Kumar, Raj
Microwave accelerated and expedited cyclocondensation reactions of 2-(3-aryl-1H-pyrazol-5-yl)anilines (4) with diverse aryl aldehydes/triethyl orthoformate in water/MeCN (route D) and internal cyclocondensation and aromatization of 5-(2-aminophenyl)-4,5-dihydro-3-arylpyrazole-1-carbaldehyde (7) under MeOH (route E) for the synthesis of a series of pyrazolo[1,5-c]quinazolines and their derivatives (1a–1q) are reported.
Impact of ABC transporters, glutathione conjugates in MDR and their modulation by flavonoids: An overview
(2014) Gupta, Vinay Kumar; Bhalla, Yashika; Jaitak, Vikas
Overexpression of ATP-binding cassette (ABC) transporter and glutathione conjugates results in efflux of cytotoxic agent from tumor cells leading to multidrug resistance (MDR). Many MDR inhibitors have been identified but none of them have been proven clinically valuable without side effects. Efforts are continue to develop an ideal MDR inhibitor. Recently, herbal modulation of ABC transporter and glutathione conjugates by flavonoids is emerging as popular therapy in MDR. In this review, we have covered structure, function of different ABC transporters and glutathione-mediated MRP overexpression. This review also focuses on the problems with existing MDR inhibitors, modulation of ABC transporter and glutathione-S-transferase by flavonoids. ? 2013 Springer Science+Business Media New York.
2-(2-Arylphenyl) benzoxazole As a Novel Anti-Inflammatory Scaffold: Synthesis and Biological Evaluation
(ACS publications, 2014) Seth, Kapileswar; Garg, Sanjeev K.; Kumar, Raj; Purohit, Priyank; Meena, Vachan S.; Goyal, Rohit; Banerjee, Uttam C.; Chakraborti, Asit K.
The 2-(2-arylphenyl)benzoxazole moiety has been found to be a new and selective ligand for the enzyme cyclooxygenase-2 (COX-2). The 2-(2-arylphenyl)benzoxazoles 3a−m have been synthesized by Suzuki reaction of 2-(2-bromophenyl)benzoxazole. Further synthetic manipulation of 3f and 3i led to 3o and 3n, respectively. The compounds 3g, 3n, and 3o selectively inhibited COX-2 with selectivity index of 3n much better than that of the COX-2 selective NSAID celecoxib. The in vivo anti-inflammatory potency of 3g and 3n is comparable to that of celecoxib and the nonselective NSAID diclofenac at two different doses, and 3o showed better potency compared to these clinically used NSAIDs.