Abstract This paper discusses how ever since the "Thalidomide" incidence last century there has been an ever-increasing amount of resources injected into optical isomeric research and in attaining pure enantiomeric products. It shows how due to different stereochemical characteristics, different isomers will have different interactions with biological receptors in the body, giving rise to different actions. A resultant undesirable effect is therefore inherently possible upon the consumption of chiral drugs, for that reason it is imperative that the end drug mixture is as entiomerically pure as possible. It describes the 3 basic methodologies for single enantiomers: chirality pool, kinetic resolution and asymmetric synthesis and examines the basis of and the techniques of separating them.
From the Paper "One way of the use of chirality pool molecules merely requires the maintenance of pre-existing chirality throughout a synthesis, with transformation of other parts of the molecule by formation of new chemical bonds or inter-conversion of functional groups. Otherwise, utilising chirality pool can afford a so-called "control element" for the creation of new stereogenic centres by "substrate-directable" reactions. Such reactions may involve complete transfer of chirality from one region to another intra-molecularly.[1]"
Abstract This paper provides an overview of how DSL technology works, looks at the differences between ADSL (assymetric DSL) and DSL, describes which situations both technologies are more suited for, explains the vast applications of DSL technology and then takes a look at some of the shortcomings of DSL technology.
From the Paper "On May 24, 1844 Samuel Morse-inventor of the telegraph-relayed the first message ever sent electronically: "What hath God wrought!" (Reynolds 9). Clearly, Morse comprehended some of the implications this momentous achievement suggested. It is unlikely, however, that anyone fully grasped what the future would hold for communications. From the telegraph to the telephone to the internet, it appears that man-not God-demands ever progressive technologies to exchange ideas and information with those distanced from him. "This long history of technical innovation in communications ultimately brought forth an era of inexpensive high-speed data services." (Reynolds 9)."
