Chemistry Articles

About Author:
D. J. Kalena^*, C. N. Patel
Department of Quality Assurance,
Shri Sarvajanik Pharmacy College,
Near arvind baug, Mehsana - 384 001, Gujarat, India

ABSTRACT
Combination therapy of Atorvastatin calcium (AT) and Olmesartan medoxomil (OLM) is used for the treatment of coexisting essential hypertension and hyperlipidemia in adult persons. In the present study a simple, precise, rapid, efficient and reproducible reversed?phase high performance liquid chromatography (RP?HPLC) method has been developed for the simultaneous estimation of AT and OLM present in its tablet dosage forms. Chromatographic separations were carried out isocratically at 30°C ± 0.5°C on a Kromasil C18 Column (5 μm, 250mm x 4.60mm) with a mobile phase composed of Methanol: Acetonitrile: Water (pH 3.65) in the ratio of 50:27:23 % v/v at a flow rate of 1.0 ml/min. Detection is carried out using a UV detector at 260 nm. The retention times for AT and OLM were 5.3 ± 0.5 min and 3.4 ± 0.5 min respectively. The linearity range for AT and OLM were found to be 10?60 μg/ml and 20?120μg/ml with correlation coefficient of 0.996 and 0.999 respectively. The %recovery of the proposed method was found in the range of 98.36-100.91 for AT and 99.27-100.99 for OLM. The relative standard deviations for three replicate measurements in three concentrations of standard solution were always less than 2%. The results of the study showed that the proposed RP?HPLC method is simple, rapid, precise and accurate, which may be useful for the routine estimation of AT and OM in bulk drug and in its pharmaceutical dosage form.

About Authors:
Ratnadeep V. Ghadage (M. Pharmacy)
Department of Pharmaceutical Chemistry,
Appasaheb Birnale College of Pharmacy,
South Shivaji Nagar, Sangli-416416,
Maharashtra

ABSTRACT:
Quinoxaline derivatives have emerged as an important class of benzoheterocycles because of their diverse pharmacological and biological properties, which make them privileged structures in combinatorial drug discovery libraries. Also Quinoxaline derivatives constitute useful intermediates in organic synthesis. The pharmaco-logical importance of quinoxalines and their utility as building blocks in organic synthesis have directed considerable research activities toward the synthesis of suitably substituted quinoxaline rings. Extensive researches have generated numerous synthetic approaches for the construction of the skeleton of such heterocycles. Quinoxalines are, in general, comparatively easy to prepare, and numerous derivatives have been designed and prepared for potential use as biologically active materials. Oxidation of both nitrogen of the quinoxaline ring dramatically increases the diversity of certain biological properties.
Quinoxalines, including their fused-ring derivatives, display diverse pharmacological activities.A number of synthetic strategies have been developed for the preparation of substituted quinoxalines. The classical synthesis of quinoxalines involves the condensation of an aromatic 1, 2-diamine with a 1, 2-dicarbonyl compound. The reaction is facile and is the most widely used synthetic method for both quinoxaline itself and its derivatives. Despite remarkable efforts,the development of an effective method for the synthesis of quinoxalines is still an important challenge.

About Author:
Sugumaran M., T. Vetrichelvan
Department of Pharmaceutical Chemistry,
Adhiparasakthi College of Pharmacy,
Melmaruvathur - 603 319, Tamilnadu , India

Abstract
High performance thin layer chromatographic finger print parameters had been developed for  Piper betle leaf oilisolated from karpoori, sirugamani and vellaikodi variety available in tamilnadu to fix standards. At shorter wavelength (254 nm) resolution was better for, so, this wavelength can be taken for obtaining optimum HPTLC finger printing for  volatile oil of this medicinal plant leaves. As per the data,   Karpoori variety of piper betle leaf oil  only showed  presence of  eugenol content. So, essential oil obtained from this variety should be included in the commercial tooth paste to get  antimicrobial activity against dental pathogens when compared to other studied variety.

About Authors:
Md. Sofiqul Islam, Madhusudan N. Purohit
Department of Pharmaceutical Chemistry,
JSS college of Pharmacy, Mysore 570015

Quinoline and its derivatives are well  known for their antimalarial and antibacterial propertites. A number of quinoline derivatives are known to possess antimicrobial, antitumor, antifungal, hypotensive, anti HIV, analgesics and anti-inflamatory activites. Application of quinoline derivative are fast spreading from antimalarial drugs to almost every branch of medicinal chemistry. Substitution of halogen group in a suitable position of a bioactive molecule is found to exert a profound pharmacological effect.

About Author: *Ghadage Ratnadeep V., Shah Vishal V., Bapat Bhushan A., Shirote Pramod J.
Department of Pharmaceutical Chemistry,
Appasaheb Birnale College of Pharmacy,
South Shivaji Nagar, Sangli, Maharashtra, India - 416 416

Abstract:
Quinoxaline and its derivatives are an important class of benzoheterocycles displaying a broad spectrum of biological activities which have made them privileged structures in pharmacologically active compounds.Quinoxaline also called benzopyrazine it has been considered as a wonder nucleus which posses almost all types of biological activities. This diversity in the biological response profile has attracted the attention of many researchers to explore this skeleton to its multiple potential against several activities. They are clinically effective as antibacterial, antifungal, anti-inflammatory, anticancer, anti-tubercular and antineoplastic agents. Interestingly, it also shows anti-HIV and anti-proliferative activity. Modification in their structure has offered a high degree of diversity that has proven useful for the development of new therapeutic agents having improved potency and lesser toxicity. Considering the extensive research on quinoxaline in the past, it was essential to review the wide spectrum of biological activity of quinoxalines. To conclude, this review will be beneficial for new drug discovery of quinoxaline moiety. Present article is sincere attempt to review wide range of biological activities of quinoxline moiety  given by researcher.

About Author: Dhaval G. Shah^*, Dr Manish J. Patel, Dr Laxman J. Patel
Department Of Pharmaceutical Chemistry,
Shree S. K. Patel College Of Pharmaceutical Education & Research,
Ganpat University, Kherva. Dist: Mahesana, Gujarat

Abatract
Human Immunodeficiency Virus is the causative agent of Acquired Immuno Deficiency Syndrome (AIDS), a disease which has claimed twenty millions lives worldwide in the last two decades. Recently Imidazole derivatives, such as N-aminoimidazoles (NAIMS) have been discovered as novel anti- HIV agents. Herein, the results of 2D-QSAR analysis on these inhibitors have been reported. Quantitative Structure Activity Relationship studies have been conducted on a series (25 compounds) of NAIMS with selective HIV inhibition activity using ChemOffice v.8.0 software. The best prediction have been obtained for anti-HIV activity (R²=0.82, Q²=0.73). The equation emphasized the importance of MORAN AUTOCORELATION (BY ATOMIC MASS), GAERY AUTOCORELATION (BY ATOMIC SENDERSON ELECTRONEGATIVITY), SHAPE PROFILE(RANDIC MOLECULAR PROFILE), MAXIMAL  ELECTROTOPOLOGICAL EGATIVE VARIATION and Km parameters on biological activity. The equation is validated by test set (8 compounds). The information obtained from this 2D- QSAR may be utilized in the design of more potent NAIMS analogs and anti-HIV agents.

About Author: Mr. Naresh. M. Reddy
PG Diploma (Cheminformatics),
Nizam College, Osmania University
Hyderabad.

Abstract
Oral strontium ranelate is an alternative oral treatment, belonging to a class of drugs called dual action bone agents. The objective of this investigation was to characterize and determine the effect of the Strontium ranelate on Calcium sensor receptor (CASR) which is an important protein involved Osteophoresis. Homology modeling of CASR has been performed based on the crystal structure of the 2E4U (Chain A) by using Modeller software. With the aid of the molecular mechanics and molecular dynamics methods, the final model is obtained and is further assessed by procheck and verify 3D graph programs, which showed that the final refined model is reliable. With this model, a flexible docking study of CASR with a group of Ranelic acids were selected from the previous publications was performed. The results indicated that VAL1,SER18,SER2,GLU241 in CASR are important determinant residues in binding as they have strong hydrogen bonding with Ranelic acids. These hydrogen binding interactions play an important role for stability of the complex. Among the 15 compunds, 6th showed best docking result. Our results may be helpful for further experimental investigations.

About Author: Jadhav Ramulu 1, P. Goverdhan2
1 Vaagdevi College of Pharmacy, Hanamkonda-Warangal (Affiliated to Kakatiya University), A.P-506002, INDIA
2 Head of the department, pharmacology, Vaagdevi College of Pharmacy, Hanamkonda-Warangal, A.P-506002, INDIA

Abstract
Computer aided drug design(CADD) is an emerging tool for research and drug development process as it reduce the time taken for the process of drug development and expense. Several new technologies have been developed and applied in drug R & D to shorten the research cycle and to reduce the expenses. In computer aided drug design process so many computational tools are used such as over viewing tools, homology modeling, and homology modeling programs, molecular dynamics, molecular docking and QSAR descriptors. This article provides a brief idea on computer aided drug design process and list of software used.

About Author: Ashish Chauhan
M.Pharm (Pharmaceutical Chemistry)
Department of Pharmaceutical Sciences,
Lovely Professional University, Jalandhar (Punjab).

The Montreal Protocol on Substances that Deplete the Ozone Layer
(A Protocol to the Vienna Convention for the Protection of the Ozone Layer)

Ozone Layer

• The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O3).
  
• This layer absorbs 97–99% of the Sun's high frequency ultraviolet light, which is damaging to life on Earth.
  
• It is mainly located in the lower portion of the stratosphere from approximately 30 to 40 kilometres above Earth, though the thickness varies seasonally and geographically.
  
• The ozone layer was discovered in 1913 by the French physicists Charles Fabry and Henri Buisson.
  
• Its properties were explored in detail by the British meteorologist G. M. B. Dobson, who developed a simple spectrophotometer (the Dobson meter) that could be used to measure stratospheric ozone from the ground.
  
• Between 1928 and 1958 Dobson established a worldwide network of ozone monitoring stations, which continue to operate to this day.
  
• The "Dobson unit", a convenient measure of the columnar density of ozone overhead, is named in his honour.

About Authors: Manoj Kumar Jadia1*, Dr. U. L. Narayan2
1. Department of Pharmaceutical Chemistry,
Indira Gandhi institute of Pharmaceautical Sciences,
IRC village, Bhubaneswar, Odhisa, India
2. Principal, Department of Pharmaceutical Chemistry,
Indira Gandhi institute of Pharmaceautical Sciences,
IRC village, Bhubaneswar, Odhisa, India

Abstract
The two methods are described for the simultaneous determination of Paracetamol and Etodolac in binary mixture. The first method was based on UV-spectrophotometric determination of both of the drugs, using simultaneous equation method. It involves absorbance measurement at 256.0 nm (λmax of Paracetamol) and 226.0 nm (λmax of Etodolac) in methanol; linearity was obtained in the range of 5 – 25 μg.mL-1 for both the drugs. The second method was based on HPLC separation of the two drugs in reverse phase mode using Promosil C18 column. Linearity was obtained in the concentration range of 30-70μg.mL-1 for Paracetamol and 20-60 μg.mL-1 for Etodolac. The LOD and LOQ value of UV-Spectrophotometric determination was found to be 167.43 ng mL-1, 507.37 ng mL-1  and for HPLC determination was found to be 1653.12 ng mL-1, 5009.48 ng mL-1.Both these methods have beensuccessively applied to pharmaceutical formulation and were validated according to ICH guidelines.