Contents-1. Prologue. 2, Simple Dioxetanes and the Biradical Mechanism of their Decomposition. 3. Formation of π, π* and Singlet Excited States. 4. CIEEL Mechanism. 5. Synthesis of Chemiluminescent Substances with High Quantum Efficiency. 6. Epilogue.
It is well known that the lipids carrying unsaturated fatty acids are susceptible to oxidation or peroxidation resulting free radical formation. Lipid peroxide or free radical gives generally the damage on cell membrane structure, especially on enzyme system. From these reasons, the relations between clinical symptoms and oxidized serum or organs have recently been investigated. The relations on several organs are described as follows : 1) Lung. Lung is the most active organ synthesizing phospholipids, because the inside of alvolis are wetted by the solution of surface active substance so called pneumosurfactant to decrease the surface tension of water layer on the surface of alvolis. If we give O3 or NO2 gas to rats or rabbits by respiration they die more faster without the administration of tocopherols than the animals in normal conditions. 2) Liver. In liver disease, the peroxide value of serum is in parallel to the condition of disease. It is recommended to decrease its value even in the case of surgery operation with large amounts of blood transfusion. 3) Brain. In adult brain, the deposit of yellow pigments on the surface of brain tissue is found. The pigments are identified as fuchsin bases which are attributed to the condensation between malondialdehyde, product from lipid peroxidation and amino compound. But unfornutately, the relation between the formation of fuchsin base, so called lipofuscin and the deterioration of the functions of brain has never been clarified. There are a few procedures to assay the content of peroxided products in serum or organs. Thiobarbituric acid method (TBA) is widely utilized according to its easiness, but this method has many defects or doubts to measure the peroxidized products. According to Tappel et al, the procedure for fluorescent spectra has been developed, which is due to the fluorescent product formation between malonaldehyde and amino compounds.
This article is intended to provide a survey of non-conventional reactions of benzenoid compounds which occur as a consequence of “ipso” attack of electrophiles. Included are substitution reactions accompanied by rearrangement, addition reactions followed by various transformations of addition products, reactions on lateral substituent groups, nuclear oxidation to unsaturated cyclic ketones, aryl coupling, and several other related reactions. Some efforts have been made to collect and systematize a wide variety of the “unusual” results which scatter in recent literature.
Cross aldol reactions, which were recently developed, were reviewed. The useful methods for the synthesis of cross aldols utilizing 1) lithium enolates, 2) lithio derivatives of imines and hydrazones, ; 3) magnesium, zinc and aluminium enolates 4) vinyloxyboranes 5) enol derivatives and Lewis acids were mainly discussed
This review deals with the progress toward the total synthesis of maytansinoids including synthetic studies of 4 partial structures of maytansine, that is, northern zone, eastern zone, southern zone, and western zone as well as total synthesis of (±) -N-methylmaysenine. Bioorganic chemical studies are also described.
Recent advances in chemistry of superoxide are surveyed in respect of (i) structure and properties, (ii) generation and preparation, (iii) detection, (iv) organic reactions, and (v) superoxide and singlet oxygen.