The presence of ergothioneine in the central nervous system and its probable identity with the cerebellar factor

1. Ergothioneine has been detected and quantitatively estimated in the brains of mice, rats, guinea-pigs, rabbits, cats and sheep. It is present in the cerebellum in amounts ranging from about 3.0 mug/g in the cat to 10 mug/g in the guinea-pig. Amounts in the cerebral hemispheres are much smaller, ranging from < 0.1 mug/g in the cat to 1.6 mug/g in the guinea-pig.2. Large amounts of ergothioneine (about 30 mug/g) were found in the optic nerves of the rabbit. None was detected in the dorsal columns of the spinal cord of the same species.3. Ergothioneine has an excitatory action on the electrical activity of the cerebellum of the decerebrate rabbit and the excitatory actions of cerebellar extracts on this preparation are completely accounted for by their contained ergothioneine.4. It is concluded that the cerebellar factor of Crossland & Mitchell (1956) is identical with ergothioneine.

Instrumental Methods for the Analysis of Polymeric Materials

Advances in our knowledge of the chemical and physical structure of polymeric substances have been due in large measure to new and improved instrumental methods of analysis. From the standpoint of chemical structure all polymers have at least one functional group, often in low concentration, e.g., an end group. Principal progress has been made, first, in identification of these groups, and, more recently, in their quantitative determination and location within the molecule. In some cases conventional chemical methods have been greatly improved to provide the high sensitivity required for these analyses, particularly for groups such as acid, amine, ester and carbonyl. However, most chemical methods depend on reaction in solution. Often the choice of solvent is limiting, since it must be inert toward both the sample and the reagents as well as be capable of dissolving a significant amount of the material to be analyzed. In many cases a suitable solvent is not available. Many of these restrictions do not apply to instrumental techniques. Infrared spectrophotometric methods, for example, may be (a) nondestructive and the sample can be recovered for other studies, (b) rapid, often being completed within several minutes, (c) direct in which films or dispersions can be handled and, therefore, limited solubility is not a problem, (d) capable of providing information on physical as well as chemical structure, and (e) capable of supplying other useful information during the course of an analysis. Examples of techniques used in analyses for chemical and physical structure are: (see PDF for table) This paper reviews primarily recent advances in instrumental techniques which have been shown to be capable of quantitative analysis for chemical structure. Also, reference is made to the use of infrared spectroscopy, nuclear magnetic resonance spectroscopy, and differential thermal analysis in studies of physical structure. Applications to characterizations of elastomers are emphasized, although for illustrative purposes investigations of other polymers often are discussed.

Oxidations with Iodosobenzene Diacetate. VII. The oxidation of p-Nitro-N-methylaniline

The reaction of p-nitro-N-methylaniline with iodosobenzene diacetate has been investigated in both benzene and acetic acid solution. The relative amount of the oxidant has been varied. The nature of the products indicates that extensive demethylation occurs. Tetramethylbenzidine is formed when dimethylaniline is oxidized in benzene. The mechanisms of these reactions are discussed.