More Active Products

A more active product is obtained by the following slight modification of the above procedure. Dissolve the succinimide in a slight molar excess of sodium hydroxide solution and add the bromine dissolved in an equal volume of carbon tetrachloride rapidly and with vigorous stirring. A finely crystalline white product is obtained. Filter with suction and dry thoroughly the crude product can be used directly. It may be recrystallised from acetic acid. 

Some steroid hormones are converted in the brain to more active products that interact with receptors 847... 

Fig. 1.1. General mechanism of action of steroid hormones. Steroid hormones cross through the plasmatic membrane without apparent difficulty favored by gradient. Some, which can be considered prohormones, are metabolized and transformed into more active products. This is the case with testosterone, which becomes dihydrotestosterone (DHT) in the target tissues of androgens, through the 5-alfa-reductase enzyme. The hormone binds to the receptor, a soluble protein of the cellular cytosol that, in the absence of hormone, is found associated with other proteins (hsp90 and others) that maintain the receptor in an inactive state. The hormone-receptor bond causes the other proteins to separate and a homodimer to be formed. The homodimer is the activated form of the receptor since it is capable of recognizing the genes that depend on that steroid hormone as well as of activating its expression, which leads to the synthesis of specific proteins...

The dielectric properties of oligodimethylsiloxanes and their dependence on temperature point to good dielectric characteristics of PMS liquids. Taking into consideration that PMS do not form conductive carbon particles in case of electric breakdown or sparking, it is obvious why they are used as liquid dielectrics in transformers and other electric devices. There is a law in Japan and the USA which forbids the use of nonflammable yet toxic pentachlorodiphenyl and leaves room for oligodimethylsiloxanes. This has stimulated a much more active production of PMS liquids in Japan, Germany and other countries. 

Those catalysts (REP04, NbOP04) are more active, productively speaking, than boron phosphate but they also favored C-alkylated products, mainly at high temperature. 

CONVERSION TO MORE ACTIVE PRODUCTS The conversion of cyclophosphamide to aldophosphamide and prednisone to prednisolone are examples of active com-ponnds that are converted to more active substances. 

One of the most important groups of secondary products used in the treatment of diseases are the antibiotics (E 5.2) of which some 100 products are on the market. In 1980 worldwide antibiotic production was estimated at about 25,000 tons, including 17,000 tons of penicillins (D 23.3), 5,000 tons of tetracyclines (D 3.3.7), 1,200 tons of cephalosporins (D 23.3) and 800 tons of erythromycins (D 4). The search for new antibiotics continues because of the development of new resistant strains and the need for cheaper, safer, and more active products. Chemical modification of natural antibiotics is of increasing significance in this respect. Antibiotics are not only used in human or veterinary medicine, but on a large scale also for growth promotion of farm animals. 

It is estimated that there are in USA about 80,000 injection molding machines (IMMs) and about 18,000 extruders operating. This difference in the amount of machines is due the fact that there is more activity (product design, R8cD, fabrication, etc.) required with injection molding (IM). 

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