Drugs : photochemistry and photostability : [proceedings of the 2nd international meeting on photostability of drugs, held in Pavia, Italy, 4-17 September 1997

Since Pasteur in 1846, scientists have been aware that many drugs are photoreactive, but until recently research in this area had been somewhat limited. However, since the introduction of acutely sensitive analytical methods, the realisation of the need to identify the photochemical properties of a potential drug as early in its development as possible and the increased attention to the phototoxic effect of drugs, more details are becoming available. Drugs: Photochemistry and Photostability presents the basic elements of the science, and serves as an excellent introduction to this emerging field of photochemistry. Detailed experimental conditions for photostability studies are given, along with a discussion of the recently implemented ICH Guidelines for drug photostability. With contributions from international experts in the field and including a comprehensive literature review, this book provides all the up-to-date information needed by researchers in many fields, especially medicinal and pharmaceutical chemistry. Cover......Page 1 Front Page......Page 3 Preface......Page 7 Contents......Page 9 Photochemistry of Drugs: An Overview and Practical Problems......Page 11 Medicinal Photochemistry (An Introduction with Attention to Kinetic Aspects)......Page 84 Photoreactivity of Selected Antimalarial Compounds in Solution and in the Solid State......Page 97 Photochemistry of Diuretic Drugs in Solution......Page 110 New Results in the Photoinstability of Antimycotics......Page 126 Photoreactivity versus Activity of a Selected Class of Phenothiazines: A Comparative Study......Page 144 Photoprocesses in Photosensitising Drugs Containing a Benzophenone-like Chromophore......Page 160 Photostability of Coumarin......Page 172 Photostabilities of Several Chemical Compounds used as Active Ingredients in Sunscreens......Page 181 An Analytical and Structural Study of the Photostability of some Leukotriene B4 Antagonists......Page 192 Molecular Mechanisms of Photosensitization Induced by Drugs on Biological Systems and Design of Photoprotective Systems......Page 204 A Comparison between the Photochemical and Photosensitising Properties of Different Drugs......Page 221 Photostability of Drug Substances and Drug Products: A Validated Reference Method for Implementing the ICH Photostability Study Guidelines......Page 237 The Elaboration and Application of the ICH Guideline on Photostability : A European View......Page 253 Selecting the Right Source for Pharmaceutical Photostability Testing......Page 257 Design and Validation Characteristics of Environmental Chambers for Photostability Testing......Page 282 Design Limits and Qualification Issues for Room-size Solar Simulators in a GLP Environment......Page 298 Actinometry : Concepts and Experiments......Page 305 trans-2-Nitrocinnamaldehyde as Chemical Actinometer for the UV=A Range in Photostability Testing of Pharmaceuticals......Page 315 Subject Index......Page 327 Back Cover......Page 337 Absorption of light (UV or visible) by the ground state of a molecule (So) generates electronically excited states, either directly (the singlet states) or after intersystem crossing from the singlet manifold (the triplet states).