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Pharmaceutical Review and Its Importance of Chiral IJRPC 2016, 6(3), 476-484 Purushoth Prabhu et al. ISSN: 22312781 INTERNATIONAL JOURNAL OF RESEARCH IN PHARMACY AND CHEMISTRY Available online at www.ijrpc.com Review Article PHARMACEUTICAL REVIEW AND ITS IMPORTANCE OF CHIRAL CHROMATOGRAPHY Purushoth Prabhu T1*, Shinesudev2, Manju kurian2, Manjushsa P2, Minnu PS2, Mohamed Hisham C2 and Sapna Shrikumar2 1C.L.Baid Metha College of Pharmacy, Chennai, Tamil Nadu, India. 2Moulana College of Pharmacy, Angadippuram P.O., Perinthalmanna, Malappuram (DT) – 679321, Kerala, India. ABSTRACT The separation of chiral compounds has been of. great interest because the majority of bioorganic molecules are chiral. Living organisms, for example, are composed of chiral biomolecules such as amino acids, sugars, proteins and nucleic acids. In nature these biomolecules exist in only one of the two possible enantiomeric forms, e.g., amino acids in the L-form and sugars in the D-form in our body. In this article we had an attempt to review about chiral chromatography and its pharmaceutical importance. INTRODUCTION materials in plant life, a Russian botanist The separation of chiral compounds has been invented chromatography in 1903. His name of great interest because the majority of was M.S. T.S.wett. Chromatography is such bioorganic molecules are chiral. Living an important technique that two nobel prizes organisms, for example, are composed of have been awarded to chromatographers. chiral biomolecules such as amino acids, Over 60% of chemical analysis worldwide is sugars, proteins and nucleic acids. In nature currently done with chromatography or a these biomolecules exist in only one of the two variation there on. Chromatography is used in possible enantiomeric forms, e.g., amino acids many different ways. Some people use in the L-form and sugars in the D-form in our chromatography to find out what is in a solid or body. a liquid. It is also used to determine what unknown substances are. The Police, F.B.I., Chromatography and other detectives use chromatography Some materials appear homogenous, but are when trying to solve a crime. It is also used to actually a combination of substances. For determine the presence of cocaine in urine, example, green plants contain a mixture of alcohol in blood, and lead in water. different pigments. In addition, the black ink in Chromatography is used by many different the pens that are used in this experiment is a people in many different ways. mixture of different coloured materials. In Chromatography is based on differential many instances, we can separate these migration. The solutes in a mobile phase go materials by dissolving them in an appropriate through a stationary phase. Solutes with a liquid and allowing them to move through an greater affinity for the mobile phase will spend absorbent matrix, like paper. Chromatography more time in this phase than the solutes that is a method used by scientists for separating prefer the stationary phase. As the solutes organic and inorganic compounds so that they move through the stationary phase they can be analyzed and studied. By analyzing a separate. This is called chromatographic compound, a scientist can figure out what development. makes up that compound. Chromatography is Pharmacologically active compounds (PACs) a great physical method for observing mixtures are widely regarded as emerging and solvents. contaminants and many of them possess at The word chromatography means "colour least one stereogenic centre. The aim of this writing" which is a way that a chemist can test paper is to introduce the subject of chirality liquid mixtures. While studying the colouring within PACs and its implications in 476 IJRPC 2016, 6(3), 476-484 Purushoth Prabhu et al. ISSN: 22312781 environmental contamination. The paper pair of enantiomers in drugs, pesticides, or describes contemporary techniques utilized in waste compounds, etc. the analysis of chiral contaminants and Chirality is a major concern in the modern provides a critical review of the methods pharmaceutical industry. This interestcan be employed and results gained in the field. attributed largely to a heightened awareness that enantiomers of a racemic drug may have Phenomenon of chirality different pharmacological activities, as well as Enantiomers are molecular entities which are different pharmacokinetic and non-super imposable mirror images. The pharmacodynamic effects. The body being chirality (handedness) of enantiomeric amazingly chiral selective, will interact with molecules is caused by the presence of one or each racemic drug differently and metabolize more chiral elements (chirality axis, chirality each enantiomer by a separate pathway to plane, or chirality centre, e.g., asymmetric produce different pharmacological activity. carbon atom) in the structure. The chirality and Thus, one isomer may produce the desired optical activity of the enantiomers is therapeutic activities, while the other may be determined by their absolute configuration, inactive or, in worst cases, produce unwanted i.e., the spacial arrangement of the atoms in effects. Consider the tragic case of the the molecule. racemic drug of n-phthalyl-glutamic acid imide that was marketed in the 1960‟s as the Nomenclature sedative Thalidomide. Its therapeutic acitivity IUPAC approved naming system is the Cahn- resided exclusively in the R-(+)-enantiomer. It Ingold and Prelog designation for four- and was discovered only after several hundred six-coordinate stereogenic centres, pre-fixed births of malformed infants that the S-(+)- with R or S, when discussing molecules with enantiomer was teratogenic. planar chirality . Dextro and Levo (+/_) may The U.S. Food and Drug Administration(U.S. also be used to describe enantiomers where F.D.A), in 1992, issued a guideline that for the absolute configuration may not be known chiral drugs only its therapeutically active or to describe the rotation of light under isomer be brought to market, and that each prescribed conditions, although the prefixes „d‟ enantiomer of the drug should be studied and „l‟ are discouraged. separately for its pharmacological and metabolic pathways. In addition, a rigorous Chirality in pharmaceuticals justification is required for market approval of a Two enantiomers of the same compound, racemate of chiral drugs. Presently, a majority despite having the same physical and of commercially available drugs are both chemical properties, show different synthetic and chiral. However, a large number interactions with other chiral molecules due to of chiral drugs are still marketed as racemic differences in spacial arrangement of the mixtures. Nevertheless, to avoid the possible atoms and therefore binding affinity. This undesirable effects of a chiral drug, it is phenomenon is particularly significant in imperative that only the pure, therapeutically biological interactions as all proteins, enzymes active form be prepared and marketed. Hence and carbohydrates are chiral . Thus organisms there is a great need to develop the might respond uniquely to each enantiomer, a technology for analysis and separation of phenomenon discovered by Pasteur in 1857 . racemic drugs. This is of particular importance in the case of Chiral compounds are also utilized for chemicals such as PACs and pesticides, asymmetric synthesis, i.e., for the preparation which are designed to illicit biological action of pure optically active compounds. They are also used in studies for determining reaction Chiral Separation mechanisms, as well as reaction pathways. The separation of chiral compounds has been Chiral compounds are also important in the of great interest because the majority of agrochemical industries. Current methods of bioorganic molecules are chiral. Living enantiomeric analysis include such non- organisms, for example, are composed of chromatographic techniques as polarimetry, chiral biomolecules such as amino acids, nuclear magnetic resonance, isotopic dilution, sugars, proteins and nucleic acids. In nature calorimetry, and enzyme techniques. The these biomolecules exist in only one of the two disadvantages of these techniques are the possible enantiomeric forms, e.g., amino acids need for pure samples, and no separation of in the L-form and sugars in the D-form in our enantiomers are involved. Quantitation, which body. Because of chirality, living organisms does not require pure samples, and separation show different biological responses to one of a of enantiomers can be done simultaneously by either gas chromatography (GC) or high 477 IJRPC 2016, 6(3), 476-484 Purushoth Prabhu et al. ISSN: 22312781 performance liquid chromatography (HPLC). difficult. The decision relies mostly on Chiral HPLC has proven to be one of the best empirical data. Most chiral separations methods for the direct separation and analysis achieved on CSPs, however, were obtained of enatiomers. It is more versatile than chiral based upon the accumulated trial-and-error GC, because it can separate a wide variety of knowledge of the analyst, intuition, and often nonvolatile compounds. It provides fast and simply by chance. An alternative way of accurate methods for chiral separation, and choosing a CSP is by using predictive allows on-line detection and quantitation of empirical rules that have been developed both mass and optical rotation of enantiomers based on empirical structures. Neither scheme if appropriate detection devices are used. of choosing a right CSP offers a guarantee for Current chiral HPLC methods are either direct, a successful enantiomeric separation.
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