Photochemical Reactions Involved The Intramolecular Electron Transfer Or Energy Transfer

DNA is damaged by ultraviolet component from sunlight to give a variety of potentially mutagenic photoproducts. The pyrimidine cyclobutane dimers are the most abundant photoproducts among the major two types of photoinduced DNA damages. This lesion will block replication and transcription of DNA, leading to cytotoxic and mutagenic effects. The pyrimidine(6-4)pyrimidone adducts, simply termed (6-4) photoproducts, constitute a second class of stable photoproducts in DNA and also play a role in UV-induced cytotoxic damage. Cells protect themselves against these effects by eliminating these photoproducts from their genome either by excision or by photoreactivation under near UV and visible light, the latter is catalyzed by photolyase.The cis-trans photoisomerization reaction is an element organic photochemical reaction. It generally exists in the nature, has the important physiological function in the person and animal vision formation, and also plays an important role in many fine chemicals productions. For example in preparation vitamin A and vitamin D and its derivatives, the cis-trans photoisomerization reaction is the crucial step reaction.Photochemically removable protecting groups (PRPGs) are molecular entities that can be covlently attached to functional group of a molecule for the purpose of rendering it inert to some particular set of reaction conditions. The PRPG is then released when the protected compound is exposed light. Such protecting groups find uses not only in combinatorial chemistry but also in cell biology.In this work, we investigated the photoreaction of the model of the (6-4) photoproduct, and initially obtained the repair nature of the (6-4) photolyase. In addition, we studied the photoisomerization of the cinnamic acid derivatives resulting from intramolecular triplet-triplet energy transfer and the photochemistry of acridine-9-ylmethoxycarbonyl (Amoc), a new photochemically removable protecting group for alcohols.1. Model studies of the (6-4) photoproduct photoreactivation: efficient photosensitized...