One-Pot-Condensation Reaction of Heterocyclic Amine, 1,3-Diketone and Aldehydes Using <em>In Situ</em> Generated Superoxide Ion: A Rapid Synthesis of Structurally Diverse Drug-Like Complex Heterocycles

A novel, convenient one-pot multicomponent synthesis of tetraheterocyclicbenzimidazolo/benzothiazolo quinazolin-1-one derivatives has been reported in the presence of tetraethylammonium superoxide under non-aqueous condition. The superoxide induced three-component reaction of various aromatic aldehydes, 2-aminobenzimadazole/2-aminobenzothiazole and dimedone/1,3- cyclohexanedione produced tetraheterocyclicbenzimidazolo/benzothiazolo quinazolin-1-one derivatives at room temperature under the mild reaction conditions. The tetraethylammonium superoxide has been generated by phase transfer reaction of potassium superoxide and tetraethylammonium bromide in dry DMF at room temperature. The present study extended the applicability of tetraethylammonium bromide as a phase transfer catalyst for the efficient use of superoxide ion in multi-component synthesis of structurally diverse drug-like complex heterocycles (quinazolines)

Eco-Friendly and Facile Synthesis of Substituted Imidazoles via Nano Zirconia Catalyzed One-Pot Multicomponent Reaction of Isatin Derivatives with Ammonium Acetate and Substituted Aromatic Aldehydes under Solvent Free Conditions

An eco-friendly and highly efficient approach for the synthesis of substituted imidazoles via nano zirconia catalyzed multicomponent reaction of isatin derivatives with ammonium acetate and aromatic aldehydes under solvent-free conditions has been developed. This approach can be mostly applied to medicinal chemistry due of the simple and readily available starting materials, effortless methodology, and biologically active nature of imidazoles. An additional gain of the suggested technique is the reusability of the nano ZrO2 catalyst

Topology of Reciprocal Trade Agreements – A New Perspective

The topology of the worldwide network of reciprocal trade agreements is evolving in ways that defy conventional wisdom. It is at odds with the triad hypothesis, that is, a view of the world consisting of three mutually isolated major blocs, structured in a hub and spoke fashion - Americas with US as the hub, Europe with European Union as the hub and Asia with Japan as the hub. Moreover, many new agreements, traditionally called ‘regional’, are actually inter-regional. In order to make sense of these developments, we charted the evolution of the network using social network analysis and arrived at a new perspective on its topology

Facile transformation of aromatic aldehydes to acids mediated by tetraethylammonium superoxide

805-80

Role of human papillomavirus and its detection in potentially malignant and malignant head and neck lesions: updated review

Head and neck malignancies are characterized by a multiphasic and multifactorial etiopathogenesis. Tobacco and alcohol consumption are the most common risk factors for head and neck malignancy. Other factors, including DNA viruses, especially human papilloma virus (HPV), may also play a role in the initiation or development of these lesions. The pathways of HPV transmission in the head and neck mucosal lesions include oral-genital contact, more than one sexual partner and perinatal transmission of HPV to the neonatal child. The increase in prevalence of HPV infection in these lesions may be due to wider acceptance of oral sex among teenagers and adults as this is perceived to be a form of safe sex. The prevalence of HPV in benign lesions as well as malignancies has been assessed by many techniques. Among these, the polymerase chain reaction is the most sensitive method. Review of literature reveals that HPV may be a risk factor for malignancies, but not in all cases. For confirmation of the role of HPV in head and neck squamous cell carcinoma, large population studies are necessary in an assortment of clinical settings. Prophylactic vaccination against high-risk HPV types eventually may prevent a significant number of cervical carcinomas. Of the two vaccines currently available, Gardasil® (Merck & Co., Inc.) protects against HPV types 6, 11, 16 and 18, while the other vaccine, Cervarix® (GlaxoSmithKline, Rixensart, Belgium) protects against HPV types 16 and 18 only. However, the HPV vaccine has, to the best of our knowledge, not been tried in head and neck carcinoma. The role of HPV in etiopathogenesis, prevalence in benign and malignant lesions of this area and vaccination strategies are briefly reviewed here

Oxidative cleavage of ɑ-diketones using tetraethylammonium bromide as phase transfer catalyst

88-9

Electrogenerated superoxide induced oxidation of thiols and disulfide interchange: A functional group approach to biomimetic study

411-41

Improved On-demand Routing Protocol in Mobile Ad-hoc Network

In mobile ad-Hoc network there is no fixed topology and infrastructure. One of the most important and efficient routing protocol on the basis of energy and number of nodes is AODV distance vector routing protocol source nodes forward In this routing algorithm first it sends the route request (RREQ) to the neighbor with the range of the source and the nodes and then finds the path from one node to another. The intermediate nodes having less energy also forward packets. As the lifetime expires it falls down and the power and energy is not used in the efficient transfer of message and data. It could not forward RREP on reverse path. Hence source node has to restart again and again which results in unnecessary rebroadcast efficiency is less and packet delivery ration is also less and throughput is also less and more end to end delay. Solution of the above problem in AODV protocol is OAODV routing protocol optimized one in this node does not forward as soon as request (RREQ) reached their first it checked there is a sufficient energy (battery lifetime) and until the node density is greater than the threshold value. These two taking into consideration various statistics . Optimized AODV analyses the energy and node density by avoiding the unnecessary information sending efficiently. By comparing energy ratio and node density it proves that OAODV is much better than AODV protocol on the basis of battery lifetime, throughput, and PDR

The arithmetic mean iterative method for solving 2D Helmholtz equation

In this paper, application of the Arithmetic Mean (AM) iterative method is extended by solving second order finite difference algebraic equations. The performance of AM method in solving second order finite difference algebraic equations is comparatively studied by their application on two-dimensional Helmholtz equation. Numerical results of AM method in solving two test problems are included and compared with the standard Gauss-Seidel (GS) method. Based on the numerical results obtained, the results show that AM method is better than GS method in the sense of number of iterations and CPU time