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The ability to transfer the stereochemical information, contained within a dicobalt hexacarbonyl complexed chiral non-racemic propargyl alcohol into the resulting product still remains a challenge to the synthetic chemist. Benzopyran derivatives have a wide range of biological activity; developing a practical synthetic route to their synthesis has a huge importance in the development of new therapeutic drugs. When it comes to therapeutic drugs, their stereoselective synthesis is crucial because one of the isomers is often not only ineffective but may also be toxic. This book investigates asymmetric synthesis of chiral non-racemic propargyl alcohols and the synthesis of biologically active novel benzopyran derivatives using the Nicholas reaction. The biological testing of the newly synthesized compound revealed that they are potent anti-hypertension drug candidates. From the biological screening, the newly synthesized benzopyrans are not only active and relaxed smooth muscle but also seem to have different mode of action from that of cromakalim, the well known potassium channel opener. Hence, this book is very useful for research chemists working on drug discovery and academician.

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Kibur Hunie Tesfa, PhD: Studied Organic Chemistry at Kingston University, U.K. She pursued Post-Doctoral research in Biochemistry at the University of Toronto. She has also two Masters and a Bachelor Degree studied in France. She published a number of articles and won multiple awards. She is active in her field and lives currently in Toronto.

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