Roland E. Dolle 22.1
The synthesis of chemical libraries is now widely practiced in academic and industrial laboratories. The first examples of small-molecule libraries were collections of heterocycles, e.g. Ellman's 1,4-benzodiazepines and b-lactams from Affy-max. Of the 1250 libraries published since 1992, over 80% are based on a heterocyclic theme . The impetus for the development and application of high-speed synthesis is tied to the pharmaceutical industry's quest for discovering new biologically active agents; heterocycles enjoy a rich history of providing leads for this multibillion dollar industry. This chapter presents a systematic examination of the solid-phase synthesis of heterocycles containing a single heteroatom. This treatise is organized by atom type (nitrogen, oxygen, sulfur), ring size, and degree of unsaturation. Table 22.1A-H lists the generic structures of all solid- and solution-phase heterocyclic libraries containing a single heteroatom that were published during 1992-2000.
Was this article helpful?
With all the stresses and strains of modern living, panic attacks are become a common problem for many people. Panic attacks occur when the pressure we are living under starts to creep up and overwhelm us. Often it's a result of running on the treadmill of life and forgetting to watch the signs and symptoms of the effects of excessive stress on our bodies. Thankfully panic attacks are very treatable. Often it is just a matter of learning to recognize the symptoms and learn simple but effective techniques that help you release yourself from the crippling effects a panic attack can bring.